Refactor: Restructure project package hierarchy and add initial implementation for assembler instructions, shell commands, and exception handling.

2025-08-13 21:42:49 +02:00
parent b103631133
commit 12027fe740
135 changed files with 10835 additions and 31 deletions
--- a/.idea/.name
+++ b/.idea/.name
@@ -1 +0,0 @@
-template
--- a/.idea/artifacts/mtmc_web_js_0_1_0_SNAPSHOT.xml
+++ b/.idea/artifacts/mtmc_web_js_0_1_0_SNAPSHOT.xml
@@ -0,0 +1,8 @@
+<component name="ArtifactManager">
+  <artifact type="jar" name="mtmc-web-js-0.1.0-SNAPSHOT">
+    <output-path>$PROJECT_DIR$/build/libs</output-path>
+    <root id="archive" name="mtmc-web-js-0.1.0-SNAPSHOT.jar">
+      <element id="module-output" name="mtmc-web.jsMain" />
+    </root>
+  </artifact>
+</component>
--- a/.idea/artifacts/mtmc_web_jvm_0_1_0_SNAPSHOT.xml
+++ b/.idea/artifacts/mtmc_web_jvm_0_1_0_SNAPSHOT.xml
@@ -0,0 +1,8 @@
+<component name="ArtifactManager">
+  <artifact type="jar" name="mtmc-web-jvm-0.1.0-SNAPSHOT">
+    <output-path>$PROJECT_DIR$/build/libs</output-path>
+    <root id="archive" name="mtmc-web-jvm-0.1.0-SNAPSHOT.jar">
+      <element id="module-output" name="mtmc-web.jvmMain" />
+    </root>
+  </artifact>
+</component>
--- a/.idea/misc.xml
+++ b/.idea/misc.xml
@@ -3,7 +3,7 @@
  <component name="FrameworkDetectionExcludesConfiguration">
    <file type="web" url="file://$PROJECT_DIR$" />
  </component>
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_17" default="true" project-jdk-name="17" project-jdk-type="JavaSDK">
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_17" project-jdk-name="corretto-21" project-jdk-type="JavaSDK">
    <output url="file://$PROJECT_DIR$/out" />
  </component>
  <component name="accountSettings">
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -1,5 +1,6 @@
@file:OptIn(ExperimentalDistributionDsl::class)

+import org.codehaus.groovy.tools.shell.util.Logger.io
 import org.jetbrains.kotlin.gradle.targets.js.dsl.ExperimentalDistributionDsl

 plugins {
@@ -50,6 +51,9 @@ kotlin {
                implementation("nl.astraeus:simple-jdbc-stats:1.6.1") {
                    exclude(group = "org.slf4j", module = "slf4j-api")
                }
+
+              implementation("io.pebbletemplates:pebble:3.2.3")
+              implementation("com.google.code.gson:gson:2.12.1")
            }
        }
        val jvmTest by getting {
--- a/settings.gradle.kts
+++ b/settings.gradle.kts
@@ -1,5 +1,5 @@
 plugins {
  id("org.gradle.toolchains.foojay-resolver-convention") version "0.5.0"
 }
-val REPO_NAME = "dummy so the gitea template compiles, please remove"
+
 rootProject.name = "mtmc-web"
--- a/src/jsMain/kotlin/nl/astraeus/tmpl/Main.kt
+++ b/src/jsMain/kotlin/nl/astraeus/tmpl/Main.kt
@@ -1,11 +1,10 @@
-package nl.astraeus.tmpl
+package mtmc

 import kotlinx.browser.document
 import kotlinx.html.div
 import nl.astraeus.komp.HtmlBuilder
 import nl.astraeus.komp.Komponent

-
 class HelloKomponent : Komponent() {
  override fun HtmlBuilder.render() {
    div {
--- a/src/jvmMain/kotlin/nl/astraeus/tmpl/Main.kt
+++ b/src/jvmMain/kotlin/nl/astraeus/tmpl/Main.kt
@@ -1,4 +1,4 @@
-package nl.astraeus.tmpl
+package mtmc

 import com.zaxxer.hikari.HikariConfig
 import io.undertow.Undertow
@@ -8,8 +8,8 @@ import io.undertow.server.handlers.encoding.ContentEncodingRepository
 import io.undertow.server.handlers.encoding.EncodingHandler
 import io.undertow.server.handlers.encoding.GzipEncodingProvider
 import nl.astraeus.logger.Logger
-import nl.astraeus.tmpl.db.Database
-import nl.astraeus.tmpl.web.RequestHandler
+import mtmc.db.Database
+import mtmc.web.RequestHandler

 val log = Logger()

--- a/src/jvmMain/kotlin/mtmc/Placeholders.kt
+++ b/src/jvmMain/kotlin/mtmc/Placeholders.kt
@@ -0,0 +1,8 @@
+package mtmc
+
+val SERVER_PORT = 4001
+val JDBC_PORT = 4002
+
+val pageTitle = "mtmc-web"
+val itemUrl = "mtmc-web"
+val repoName = "mtmc-web"
--- a/src/jvmMain/kotlin/mtmc/asm/ASMElement.kt
+++ b/src/jvmMain/kotlin/mtmc/asm/ASMElement.kt
@@ -0,0 +1,19 @@
+package mtmc.asm
+
+import mtmc.tokenizer.MTMCToken
+
+abstract class ASMElement(
+  val labels: List<MTMCToken>,
+  @JvmField var lineNumber: Int
+) : HasLocation {
+  @JvmField
+  var errors: MutableList<ASMError> = ArrayList()
+  override var location: Int = 0
+  override var sizeInBytes: Int = 0
+
+  fun addError(token: MTMCToken, error: String) {
+    errors.add(ASMError(token, error))
+  }
+
+  abstract fun addError(integerValueRequired: String)
+}
--- a/src/jvmMain/kotlin/mtmc/asm/ASMError.kt
+++ b/src/jvmMain/kotlin/mtmc/asm/ASMError.kt
@@ -0,0 +1,13 @@
+package mtmc.asm
+
+import mtmc.tokenizer.MTMCToken
+
+@JvmRecord
+data class ASMError(
+  @JvmField val token: MTMCToken,
+  @JvmField val error: String
+) {
+  fun formattedErrorMessage(): String {
+    return "Line " + token.line + ": " + error
+  }
+}
--- a/src/jvmMain/kotlin/mtmc/asm/Assembler.kt
+++ b/src/jvmMain/kotlin/mtmc/asm/Assembler.kt
@@ -0,0 +1,798 @@
+package mtmc.asm
+
+import mtmc.asm.data.Data
+import mtmc.asm.graphics.Graphic
+import mtmc.asm.instructions.ALUInstruction
+import mtmc.asm.instructions.ALUOp.Companion.isALUOp
+import mtmc.asm.instructions.ErrorInstruction
+import mtmc.asm.instructions.Instruction
+import mtmc.asm.instructions.InstructionType
+import mtmc.asm.instructions.InstructionType.Companion.fromString
+import mtmc.asm.instructions.InstructionType.InstructionClass
+import mtmc.asm.instructions.JumpInstruction
+import mtmc.asm.instructions.JumpRegisterInstruction
+import mtmc.asm.instructions.LoadStoreInstruction
+import mtmc.asm.instructions.LoadStoreRegisterInstruction
+import mtmc.asm.instructions.MetaInstruction
+import mtmc.asm.instructions.MiscInstruction
+import mtmc.asm.instructions.StackInstruction
+import mtmc.asm.instructions.TestInstruction
+import mtmc.emulator.DebugInfo
+import mtmc.emulator.DebugInfo.GlobalInfo
+import mtmc.emulator.DebugInfo.LocalInfo
+import mtmc.emulator.MonTanaMiniComputer
+import mtmc.emulator.Register.Companion.isReadable
+import mtmc.emulator.Register.Companion.isWriteable
+import mtmc.os.SysCall
+import mtmc.os.exec.Executable
+import mtmc.tokenizer.MTMCToken
+import mtmc.tokenizer.MTMCTokenizer
+import java.io.File
+import java.nio.charset.StandardCharsets
+import java.util.*
+import java.util.stream.Collectors
+
+class Assembler {
+  var instructions: MutableList<Instruction> = ArrayList<Instruction>()
+  var instructionsSizeInBytes: Int = 0
+  var data: MutableList<Data> = ArrayList<Data>()
+  var graphics: MutableList<Graphic> = ArrayList<Graphic>()
+  var dataSize: Int = 0
+  var labels: HashMap<String?, HasLocation?>
+
+  private var mode: ASMMode = ASMMode.TEXT
+  var tokenizer: MTMCTokenizer? = null
+  private var lastLabels: MutableList<MTMCToken> = mutableListOf()
+  private var srcName = "disk/file.asm"
+  private var debugStrings: MutableList<String> = mutableListOf()
+
+  init {
+    labels = HashMap<String?, HasLocation?>()
+  }
+
+  fun assemble(asm: String): AssemblyResult {
+    return assemble(null, asm)
+  }
+
+  fun assemble(file: String?, asm: String): AssemblyResult {
+    tokenizer = MTMCTokenizer(asm, "#")
+    debugStrings = ArrayList<String>()
+    parseAssembly()
+    resolveLocations()
+    val errors = collectErrors()
+    var debugInfo: DebugInfo? = null
+    var code: ByteArray = ByteArray(0)
+    var data: ByteArray = ByteArray(0)
+    var graphics: Array<ByteArray> = arrayOf()
+    if (errors.isEmpty()) {
+      code = genCode()
+      data = genData()
+      graphics = genGraphics()
+      debugInfo = genDebugInfo(file, asm, code)
+    }
+    return AssemblyResult(code, data, graphics, debugInfo, errors)
+  }
+
+  private fun genDebugInfo(
+    assemblyFile: String?,
+    assemblySource: String,
+    code: ByteArray
+  ): DebugInfo {
+    val assemblyLineNumbers = IntArray(code.size)
+
+    var originalFile: String = ""
+    val originalLineNumbers = IntArray(code.size)
+
+    val globals: MutableList<GlobalInfo> = ArrayList<GlobalInfo>()
+    val locals = Array<Array<LocalInfo?>>(code.size) { arrayOf() }
+
+    var location = 0
+    var originalLineNumber = 0
+    val currentLocals: MutableMap<String?, LocalInfo?> = TreeMap<String?, LocalInfo?>()
+    for (instruction in instructions) {
+      val asmLineNumber = instruction.lineNumber
+      if (instruction is MetaInstruction) {
+        if (instruction.isFileDirective) {
+          originalFile = instruction.getOriginalFilePath()!!
+        } else if (instruction.isLineDirective) {
+          originalLineNumber = instruction.originalLineNumber
+        } else if (instruction.isGlobalDirective) {
+          globals.add(
+            GlobalInfo(
+              instruction.getGlobalName(),
+              instruction.getGlobalLocation(),
+              instruction.getGlobalType()
+            )
+          )
+        } else if (instruction.isLocalDirective) {
+          currentLocals.put(
+            instruction.getLocalName(),
+            LocalInfo(
+              instruction.getLocalName(),
+              instruction.getLocalOffset(),
+              instruction.getLocalType()
+            )
+          )
+        } else if (instruction.isEndLocalDirective) {
+          currentLocals.remove(instruction.getLocalName())
+        }
+      }
+      while (location < instruction.location + instruction.sizeInBytes) {
+        assemblyLineNumbers[location] = asmLineNumber
+        originalLineNumbers[location] = originalLineNumber
+        locals[location] = currentLocals.values.toTypedArray<LocalInfo?>()
+        location++
+      }
+    }
+
+    val debugInfo = DebugInfo(
+      debugStrings,
+      assemblyFile,
+      assemblySource,
+      assemblyLineNumbers,
+      originalFile,
+      originalLineNumbers,
+      globals.toTypedArray<GlobalInfo>(),
+      locals
+    )
+
+    return debugInfo
+  }
+
+  fun assembleExecutable(srcName: String, asm: String): Executable {
+    this.srcName = "disk/" + srcName //TODO: The prefix should be replaced with FileSystem access
+
+    val result = assemble(srcName, asm)
+    if (!result.errors.isEmpty()) {
+      throw RuntimeException(
+        "Errors:\n" + result.errors
+          .stream()
+          .map<String> { e: ASMError? -> " - " + e!!.formattedErrorMessage() }
+          .collect(Collectors.joining("\n")))
+    }
+
+    return Executable(
+      Executable.Format.Orc1,
+      result.code,
+      result.data,
+      result.graphics,
+      srcName,
+      result.debugInfo
+    )
+  }
+
+  private fun parseAssembly() {
+    while (tokenizer!!.more()) {
+      parseLine()
+    }
+  }
+
+  private fun genData(): ByteArray {
+    val dataBytes = ByteArray(dataSize)
+    for (dataElt in data) {
+      dataElt.genData(dataBytes, this)
+    }
+    return dataBytes
+  }
+
+  private fun genCode(): ByteArray {
+    val code = ByteArray(this.instructionsSizeInBytes)
+    for (instruction in instructions) {
+      instruction.genCode(code, this)
+    }
+    return code
+  }
+
+  private fun genOriginalLineNumbers(length: Int): IntArray {
+    val asmLineNumbers = IntArray(length)
+    var currentLineNumber = 0
+    var location = 0
+    for (instruction in instructions) {
+      if (instruction is MetaInstruction && instruction.isLineDirective) {
+        currentLineNumber = instruction.originalLineNumber
+      }
+      while (location < instruction.location + instruction.sizeInBytes) {
+        asmLineNumbers[location] = currentLineNumber
+        location++
+      }
+    }
+    return asmLineNumbers
+  }
+
+  private fun genGraphics(): Array<ByteArray> {
+    val graphics = Array<ByteArray>(this.graphics.size) { index ->
+      graphics[index].imageData
+    }
+
+    return graphics
+  }
+
+  private fun collectErrors(): MutableList<ASMError> {
+    val errors: MutableList<ASMError> = ArrayList<ASMError>()
+    for (instruction in instructions) {
+      errors.addAll(instruction.errors)
+    }
+    for (data in this.data) {
+      errors.addAll(data.errors)
+    }
+    for (graphic in this.graphics) {
+      errors.addAll(graphic.errors)
+    }
+    return errors
+  }
+
+  private fun resolveLocations() {
+    // assign locations
+    var offset = 0
+    for (instruction in instructions) {
+      instruction.location = offset
+      offset += instruction.sizeInBytes
+      this.instructionsSizeInBytes += instruction.sizeInBytes
+    }
+    for (data in data) {
+      data.location = offset
+      offset += data.sizeInBytes
+      dataSize += data.sizeInBytes
+    }
+    for (instruction in instructions) {
+      instruction.validateLabel(this)
+    }
+  }
+
+
+  private fun parseLine() {
+    val tokens = this.tokensForLine
+
+    if (parseMetaDirective(tokens)) {
+      return
+    }
+
+    val newMode = parseModeFlag(tokens)
+    if (newMode != null) {
+      mode = newMode
+      return
+    }
+    // label only lines are ok and propagate to the next instruction
+    val labelTokens: MutableList<MTMCToken> = maybeGetLabels(tokens)
+    val labels = ArrayList<MTMCToken>(lastLabels)
+    labels.addAll(labelTokens)
+    lastLabels = labels
+    if (tokens.isEmpty()) {
+      for (labelToken in labelTokens) {
+        val labelData = Data(labelTokens, labelToken.line)
+        if (hasLabel(labelToken.stringValue)) {
+          labelData.addError(tokens.poll(), "Label already defined: " + labelToken.stringValue)
+        } else {
+          this.labels.put(labelToken.labelValue(), labelData)
+        }
+        data.add(labelData)
+      }
+    } else if (mode == ASMMode.TEXT) {
+      parseInstruction(tokens, labels)
+    } else {
+      parseData(tokens, labels)
+    }
+  }
+
+  private fun parseMetaDirective(tokens: LinkedList<MTMCToken>): Boolean {
+    if (tokens.size >= 2 && tokens.get(0).type == MTMCToken.TokenType.AT) {
+      tokens.removeFirst()
+      val metaInstruction = MetaInstruction(tokens.removeFirst())
+      if (metaInstruction.isFileDirective) {
+        val path = requireString(tokens, metaInstruction)
+        metaInstruction.setOriginalFilePath(path)
+      } else if (metaInstruction.isGlobalDirective) {
+        val name = requireString(tokens, metaInstruction)
+        val location = requireIntegerToken(tokens, metaInstruction, Int.Companion.MAX_VALUE)
+        val type = requireString(tokens, metaInstruction)
+        metaInstruction.setGlobalInfo(name, location, type)
+      } else if (metaInstruction.isLocalDirective) {
+        val name = requireString(tokens, metaInstruction)
+        val offset = requireIntegerToken(tokens, metaInstruction, Int.Companion.MAX_VALUE)
+        val type = requireString(tokens, metaInstruction)
+        metaInstruction.setLocalInfo(name, offset, type)
+      } else if (metaInstruction.isEndLocalDirective) {
+        val name = requireString(tokens, metaInstruction)
+        metaInstruction.setEndLocalInfo(name)
+      } else if (metaInstruction.isLineDirective) {
+        val lineNumber = requireIntegerToken(tokens, metaInstruction, Int.Companion.MAX_VALUE)
+        metaInstruction.setOriginalLineNumber(lineNumber)
+      } else {
+        metaInstruction.addError("Unknown meta directive")
+      }
+      instructions.add(metaInstruction)
+      return true
+    }
+    return false
+  }
+
+  private fun parseModeFlag(tokens: LinkedList<MTMCToken>): ASMMode? {
+    if (tokens.size >= 2 && tokens.get(0).type == MTMCToken.TokenType.DOT && tokens.get(1).type == MTMCToken.TokenType.IDENTIFIER && tokens.get(
+        0
+      ).end == tokens.get(1).start && (tokens.get(1).stringValue == "data" ||
+          tokens.get(1).stringValue == "text")
+    ) {
+      return ASMMode.valueOf(tokens.get(1).stringValue.uppercase(Locale.getDefault()))
+    }
+    return null
+  }
+
+  private fun parseData(tokens: LinkedList<MTMCToken>, labelTokens: MutableList<MTMCToken>) {
+    lastLabels = mutableListOf()
+    var dataToken = tokens.poll()
+    var dataElt = Data(labelTokens, if (dataToken == null) 0 else dataToken.line)
+    if (dataToken != null) {
+      if (dataToken.type == MTMCToken.TokenType.STRING) {
+        val stringBytes = dataToken.stringValue.toByteArray(StandardCharsets.US_ASCII)
+        val nullTerminated = ByteArray(stringBytes.size + 1)
+        System.arraycopy(stringBytes, 0, nullTerminated, 0, stringBytes.size)
+        nullTerminated[stringBytes.size] = '\u0000'.code.toByte()
+        dataElt.setValue(dataToken, nullTerminated)
+      } else if (isInteger(dataToken)) {
+        val integerValue = dataToken.intValue()
+        if (integerValue > Short.Companion.MAX_VALUE || integerValue < Short.Companion.MIN_VALUE) {
+          dataElt.addError(dataToken, "Number is too large")
+        }
+        dataElt.setValue(
+          dataToken,
+          byteArrayOf((integerValue ushr 8).toByte(), integerValue.toByte())
+        )
+      } else if (dataToken.type == MTMCToken.TokenType.DOT) {
+        dataToken = tokens.poll()
+        dataElt = Data(labelTokens, dataToken.line)
+        if (dataToken.stringValue == "int") {
+          val intToken = requireIntegerToken(tokens, dataElt, MonTanaMiniComputer.MEMORY_SIZE)
+          if (intToken != null) {
+            dataElt.setValue(intToken, ByteArray(intToken.intValue() * 2))
+          }
+        } else if (dataToken.stringValue == "byte") {
+          val intToken = requireIntegerToken(tokens, dataElt, MonTanaMiniComputer.MEMORY_SIZE)
+          if (intToken != null) {
+            dataElt.setValue(intToken, ByteArray(intToken.intValue()))
+          }
+        } else if (dataToken.stringValue == "image") {
+          val stringToken = requireString(tokens, dataElt)
+          if (stringToken != null) {
+            loadGraphic(labelTokens, dataElt, stringToken)
+          }
+        } else {
+          dataElt.addError(dataToken, "only data types are .int, .byte, and .image")
+        }
+      } else if (dataToken.type == MTMCToken.TokenType.MINUS) {
+        val nextToken = tokens.poll() // get next
+        if (nextToken == null || (nextToken.type != MTMCToken.TokenType.INTEGER && nextToken.type != MTMCToken.TokenType.HEX && nextToken.type != MTMCToken.TokenType.BINARY)) {
+          dataElt.addError(dataToken, "Number is too negative")
+        } else {
+          val integerValue = -1 * nextToken.intValue()
+          if (integerValue < Short.Companion.MIN_VALUE) {
+            dataElt.addError(dataToken, "Number is too negative")
+          }
+          val joinToken = MTMCToken.join(dataToken, nextToken, MTMCToken.TokenType.INTEGER)
+          dataElt.setValue(
+            joinToken,
+            byteArrayOf((integerValue ushr 8).toByte(), integerValue.toByte())
+          )
+        }
+      } else {
+        dataElt.addError(dataToken, "Unknown token type: " + dataToken.toString())
+      }
+    }
+
+    for (labelToken in labelTokens) {
+      if (hasLabel(labelToken.stringValue)) {
+        dataElt.addError(tokens.poll(), "Label already defined: " + labelToken.stringValue)
+      } else {
+        labels.put(labelToken.labelValue(), dataElt)
+      }
+    }
+    data.add(dataElt)
+  }
+
+  private fun loadGraphic(
+    labelTokens: MutableList<MTMCToken>,
+    data: Data,
+    token: MTMCToken
+  ): Graphic {
+    val graphic = Graphic(labelTokens, token.line)
+    val filename = token.stringValue
+    val file = File(File(this.srcName).getParent(), filename)
+    val index = graphics.size
+
+    data.setValue(token, byteArrayOf(((index shr 8) and 0xFF).toByte(), (index and 0xFF).toByte()))
+    graphic.setImage(file.getPath())
+    graphics.add(graphic)
+
+    return graphic
+  }
+
+  private fun parseInstruction(tokens: LinkedList<MTMCToken>, labelTokens: MutableList<MTMCToken>) {
+    var tokens = tokens
+    var instructionToken = tokens.peekFirst()
+    if (instructionToken == null) return
+
+    lastLabels = mutableListOf()
+    if (instructionToken.type != MTMCToken.TokenType.IDENTIFIER) {
+      instructions.add(ErrorInstruction(labelTokens, instructionToken, "Invalid Token"))
+      return
+    }
+
+    tokens = transformSyntheticInstructions(tokens)
+
+    instructionToken = tokens.poll()
+    val type = fromString(instructionToken.stringValue)
+
+    if (type == null) {
+      instructions.add(
+        ErrorInstruction(
+          labelTokens,
+          instructionToken,
+          "Unknown instruction token type: " + instructionToken.stringValue
+        )
+      )
+      return
+    }
+
+    val instruction: Instruction?
+    if (type.instructionClass == InstructionClass.MISC) {
+      val miscInst = MiscInstruction(type, labelTokens, instructionToken)
+      if (type == InstructionType.SYS) {
+        val sysCallType = requireSysCall(tokens, miscInst)
+        miscInst.setSyscallType(sysCallType)
+      } else if (type == InstructionType.MOV) {
+        val toRegister = requireWriteableRegister(tokens, miscInst)
+        miscInst.setTo(toRegister)
+        val fromRegister = requireReadableRegister(tokens, miscInst)
+        miscInst.setFrom(fromRegister)
+      } else if (type == InstructionType.INC || type == InstructionType.DEC) {
+        val toRegister = requireWriteableRegister(tokens, miscInst)
+        miscInst.setTo(toRegister)
+        if (!tokens.isEmpty()) {
+          val value = requireIntegerToken(tokens, miscInst, 15)
+          miscInst.setValue(value)
+        }
+      } else if (type == InstructionType.SETI) {
+        val toRegister = requireWriteableRegister(tokens, miscInst)
+        miscInst.setTo(toRegister)
+        val value = requireIntegerToken(tokens, miscInst, 15)
+        miscInst.setValue(value)
+      } else if (type == InstructionType.MCP) {
+        val fromRegister = requireWriteableRegister(tokens, miscInst)
+        miscInst.setFrom(fromRegister)
+        val toRegister = requireWriteableRegister(tokens, miscInst)
+        miscInst.setTo(toRegister)
+        val value = requireIntegerToken(tokens, miscInst, Short.Companion.MAX_VALUE.toInt())
+        miscInst.setValue(value)
+      } else if (type == InstructionType.DEBUG) {
+        val debugString = requireString(tokens, miscInst)
+        // create a dummy int token representing the offset of the debug string in the debug info
+        val debugStringIndex = debugStrings!!.size
+        debugStrings!!.add(debugString.stringValue)
+        val value = MTMCToken(0, 0, 0, 0, debugStringIndex.toString(), MTMCToken.TokenType.INTEGER)
+        miscInst.setValue(value)
+      }
+      instruction = miscInst
+    } else if (type.instructionClass == InstructionClass.ALU) {
+      val aluInst = ALUInstruction(type, labelTokens, instructionToken)
+      if (aluInst.isBinaryOp) {
+        val toRegister = requireWriteableRegister(tokens, aluInst)
+        aluInst.setTo(toRegister)
+        val fromRegister = requireReadableRegister(tokens, aluInst)
+        aluInst.setFrom(fromRegister)
+      } else if (aluInst.isImmediateOp()) {
+        val immediateOp = requireALUOp(tokens, aluInst)
+        // TODO - validate is max or lower op
+        aluInst.setImmediateOp(immediateOp)
+
+        val toRegister = requireWriteableRegister(tokens, aluInst)
+        aluInst.setTo(toRegister)
+
+        val value = requireIntegerToken(tokens, aluInst, Short.Companion.MAX_VALUE.toInt())
+        aluInst.setImmediateValue(value)
+      } else {
+        val toRegister = requireWriteableRegister(tokens, aluInst)
+        aluInst.setTo(toRegister)
+      }
+      instruction = aluInst
+    } else if (type.instructionClass == InstructionClass.STACK) {
+      val stackInst = StackInstruction(type, labelTokens, instructionToken)
+      if (type == InstructionType.PUSH) {
+        val targetRegister = requireReadableRegister(tokens, stackInst)
+        stackInst.setTarget(targetRegister)
+      } else if (type == InstructionType.POP) {
+        val toRegister = requireWriteableRegister(tokens, stackInst)
+        stackInst.setTarget(toRegister)
+      } else if (type == InstructionType.SOP) {
+        val aluOp = requireAluOp(tokens, stackInst)
+        stackInst.setALUOp(aluOp)
+      } else if (type == InstructionType.PUSHI) {
+        val value = requireIntegerToken(tokens, stackInst, Short.Companion.MAX_VALUE.toInt())
+        stackInst.setValue(value)
+      }
+
+      // if there is a stack register specified, consume it
+      if (!tokens.isEmpty() && tokens.peekFirst().type == MTMCToken.TokenType.IDENTIFIER) {
+        val stackReg = requireReadableRegister(tokens, stackInst)
+        stackInst.setStackRegister(stackReg)
+      }
+
+      instruction = stackInst
+    } else if (type.instructionClass == InstructionClass.TEST) {
+      val testInst = TestInstruction(type, labelTokens, instructionToken)
+      testInst.setFirst(requireReadableRegister(tokens, testInst))
+      if (testInst.isImmediate) {
+        testInst.setImmediateValue(requireIntegerToken(tokens, testInst, 15))
+      } else {
+        testInst.setSecond(requireReadableRegister(tokens, testInst))
+      }
+      instruction = testInst
+    } else if (type.instructionClass == InstructionClass.LOAD_STORE) {
+      val loadInst = LoadStoreInstruction(type, labelTokens, instructionToken)
+
+      val targetReg = requireReadableRegister(tokens, loadInst)
+      loadInst.setTargetToken(targetReg)
+
+      if (loadInst.isOffset) {
+        val offsetReg = requireReadableRegister(tokens, loadInst)
+        loadInst.setOffsetToken(offsetReg)
+      }
+
+      val value = requireIntegerOrLabelReferenceToken(tokens, loadInst)
+      loadInst.setValue(value)
+
+      instruction = loadInst
+    } else if (type.instructionClass == InstructionClass.LOAD_STORE_REGISTER) {
+      val loadInst = LoadStoreRegisterInstruction(type, labelTokens, instructionToken)
+
+      val targetReg = requireWriteableRegister(tokens, loadInst)
+      loadInst.setTargetToken(targetReg)
+
+      val pointerReg = requireWriteableRegister(tokens, loadInst)
+      loadInst.setPointerToken(pointerReg)
+
+      // if there is an offset register specified, consume it
+      if (!tokens.isEmpty() && tokens.peekFirst().type == MTMCToken.TokenType.IDENTIFIER) {
+        val offsetReg = requireReadableRegister(tokens, loadInst)
+        loadInst.setOffsetToken(offsetReg)
+      }
+      instruction = loadInst
+    } else if (type.instructionClass == InstructionClass.JUMP_REGISTER) {
+      val jumpInst = JumpRegisterInstruction(type, labelTokens, instructionToken)
+      val register = requireReadableRegister(tokens, jumpInst)
+      jumpInst.setRegister(register)
+      instruction = jumpInst
+    } else if (type.instructionClass == InstructionClass.JUMP) {
+      val jumpInst = JumpInstruction(type, labelTokens, instructionToken)
+      val labelValue: MTMCToken? = maybeGetLabelReference(tokens)
+      val valueToken: MTMCToken?
+      if (labelValue != null) {
+        valueToken = labelValue
+      } else {
+        valueToken = requireIntegerToken(tokens, jumpInst, MonTanaMiniComputer.MEMORY_SIZE)
+      }
+      jumpInst.setAddressToken(valueToken)
+      instruction = jumpInst
+    } else {
+      instruction = ErrorInstruction(
+        listOf(),
+        instructionToken,
+        "Unexpected Token"
+      )
+    }
+
+    for (labelToken in labelTokens) {
+      if (hasLabel(labelToken.stringValue)) {
+        instruction.addError(tokens.poll(), "Label already defined: " + labelToken.stringValue)
+      } else {
+        labels.put(labelToken.labelValue(), instruction)
+      }
+    }
+
+    // add error if any tokens are left on the line
+    if (!tokens.isEmpty()) {
+      instruction.addError(tokens.poll(), "Unexpected Token")
+    }
+
+    instructions.add(instruction)
+  }
+
+  //===================================================
+  // tokenization helper functions
+  //===================================================
+  private fun requireSysCall(tokens: LinkedList<MTMCToken>, inst: Instruction): MTMCToken {
+    val sysCallType = tokens.poll()
+    if (sysCallType == null) {
+      inst.addError("Syscall required")
+    } else if (sysCallType.type != MTMCToken.TokenType.IDENTIFIER) {
+      inst.addError(sysCallType, "Syscall required")
+    } else if (!SysCall.isSysCall(sysCallType.stringValue)) {
+      inst.addError(sysCallType, "Unknown syscall : " + sysCallType.stringValue)
+    }
+    return sysCallType!!
+  }
+
+  private fun requireAluOp(tokens: LinkedList<MTMCToken>, inst: Instruction): MTMCToken {
+    val sysCallType = tokens.poll()
+    if (sysCallType == null) {
+      inst.addError("Syscall required")
+    } else if (sysCallType.type != MTMCToken.TokenType.IDENTIFIER) {
+      inst.addError(sysCallType, "Syscall required")
+    } else if (!isALUOp(sysCallType.stringValue)) {
+      inst.addError(sysCallType, "Unknown alu operation : " + sysCallType.stringValue)
+    }
+    return sysCallType!!
+  }
+
+  private fun requireWriteableRegister(
+    tokens: LinkedList<MTMCToken>,
+    instruction: Instruction
+  ): MTMCToken {
+    val nextToken = tokens.poll()
+    if (nextToken == null) {
+      instruction.addError("Register required")
+    } else if (nextToken.type != MTMCToken.TokenType.IDENTIFIER) {
+      instruction.addError(nextToken, "Invalid Register : " + nextToken.stringValue)
+    } else if (!isWriteable(nextToken.stringValue)) {
+      instruction.addError(nextToken, "Register not writeable : " + nextToken.stringValue)
+    }
+    return nextToken!!
+  }
+
+  private fun requireReadableRegister(
+    tokens: LinkedList<MTMCToken>,
+    instruction: Instruction
+  ): MTMCToken {
+    val nextToken = tokens.poll()
+    if (nextToken == null) {
+      instruction.addError("Register required")
+    } else if (nextToken.type != MTMCToken.TokenType.IDENTIFIER) {
+      instruction.addError(nextToken, "Invalid Register : " + nextToken.stringValue)
+    } else if (!isReadable(nextToken.stringValue)) {
+      instruction.addError(nextToken, "Register not readable : " + nextToken.stringValue)
+    }
+    return nextToken!!
+  }
+
+  private fun requireALUOp(tokens: LinkedList<MTMCToken>, instruction: Instruction): MTMCToken {
+    val nextToken = tokens.poll()
+    if (nextToken == null || nextToken.type != MTMCToken.TokenType.IDENTIFIER || !isALUOp(nextToken.stringValue)) {
+      instruction.addError("ALU operation required")
+    }
+    return nextToken!!
+  }
+
+  private fun requireString(tokens: LinkedList<MTMCToken>, instruction: ASMElement): MTMCToken {
+    val nextToken = tokens.poll()
+    if (nextToken == null || nextToken.type != MTMCToken.TokenType.STRING) {
+      instruction.addError("String required")
+    }
+    return nextToken!!
+  }
+
+  private fun requireIntegerToken(
+    tokens: LinkedList<MTMCToken>,
+    inst: ASMElement,
+    max: Int
+  ): MTMCToken {
+    val token = tokens.poll()
+    if (token == null) {
+      inst.addError("Integer value required")
+    } else if (isInteger(token)) {
+      val integerValue = token.intValue()
+      if (integerValue < 0 || max < integerValue) {
+        inst.addError(token, "Integer value out of range: 0-" + max)
+      }
+    } else {
+      inst.addError(token, "Integer value expected")
+    }
+    return token!!
+  }
+
+  private fun requireToken(
+    tokens: LinkedList<MTMCToken>,
+    type: MTMCToken.TokenType,
+    inst: ASMElement
+  ): MTMCToken? {
+    val token = tokens.poll()
+    if (token == null || token.type != type) {
+      inst.addError(token, "Token " + type.name + " required")
+    }
+    return token
+  }
+
+  private fun requireIntegerOrLabelReferenceToken(
+    tokens: LinkedList<MTMCToken>,
+    inst: LoadStoreInstruction
+  ): MTMCToken {
+    val token = tokens.poll()
+    if (token == null) {
+      inst.addError("Integer or label value required")
+    } else if (!isInteger(token) && token.type != MTMCToken.TokenType.IDENTIFIER) {
+      inst.addError(token, "Integer or label value expected")
+    }
+    return token!!
+  }
+
+
+  private val tokensForLine: LinkedList<MTMCToken>
+    get() {
+      val tokens = LinkedList<MTMCToken>()
+      if (tokenizer!!.more()) {
+        val first = tokenizer!!.consume()
+        tokens.add(first)
+        while (tokenizer!!.more() &&
+          first.line == tokenizer!!.currentToken().line
+        ) {
+          tokens.add(tokenizer!!.consume())
+        }
+      }
+      return tokens
+    }
+
+  fun hasLabel(label: String?): Boolean {
+    return labels.containsKey(label)
+  }
+
+  fun resolveLabel(label: String?): Int {
+    return labels.get(label)!!.location
+  }
+
+  internal enum class ASMMode {
+    DATA,
+    TEXT
+  }
+
+  companion object {
+    fun transformSyntheticInstructions(tokens: LinkedList<MTMCToken>): LinkedList<MTMCToken> {
+      if (!tokens.isEmpty()) {
+        val first = tokens.peekFirst()
+        if (first.type == MTMCToken.TokenType.IDENTIFIER) {
+          val stringVal = first.stringValue
+          if (stringVal.endsWith("i")) {
+            val op = stringVal.substring(0, stringVal.length - 1)
+            if (isALUOp(op)) {
+              val syntheticImmediate = tokens.removeFirst()
+              tokens.addFirst(syntheticImmediate.cloneWithVal(op))
+              tokens.addFirst(syntheticImmediate.cloneWithVal("imm"))
+            }
+          } else if (stringVal.startsWith("s")) {
+            val op = stringVal.substring(1, stringVal.length)
+            if (isALUOp(op)) {
+              val syntheticImmediate = tokens.removeFirst()
+              tokens.addFirst(syntheticImmediate.cloneWithVal(op))
+              tokens.addFirst(syntheticImmediate.cloneWithVal("sop"))
+            }
+          } else if (stringVal == "la") {
+            val syntheticImmediate = tokens.removeFirst()
+            tokens.addFirst(syntheticImmediate.cloneWithVal("li"))
+          } else if (stringVal == "ret") {
+            val syntheticImmediate = tokens.removeFirst()
+            tokens.addFirst(syntheticImmediate.cloneWithVal("ra"))
+            tokens.addFirst(syntheticImmediate.cloneWithVal("jr"))
+          }
+        }
+      }
+      return tokens
+    }
+
+    private fun maybeGetLabels(tokens: LinkedList<MTMCToken>): MutableList<MTMCToken> {
+      val labels = LinkedList<MTMCToken>()
+      while (!tokens.isEmpty() && tokens.getFirst().type == MTMCToken.TokenType.LABEL) {
+        val label = tokens.poll()
+        labels.add(label!!)
+      }
+      return labels
+    }
+
+    private fun maybeGetLabelReference(tokens: LinkedList<MTMCToken>): MTMCToken? {
+      var label: MTMCToken? = null
+      if (tokens.getFirst().type == MTMCToken.TokenType.IDENTIFIER) {
+        label = tokens.poll()
+      }
+      return label
+    }
+
+    private fun isInteger(token: MTMCToken?): Boolean {
+      return token != null && (token.type == MTMCToken.TokenType.INTEGER || token.type == MTMCToken.TokenType.HEX || token.type == MTMCToken.TokenType.BINARY)
+    }
+  }
+}
--- a/src/jvmMain/kotlin/mtmc/asm/AssemblyResult.kt
+++ b/src/jvmMain/kotlin/mtmc/asm/AssemblyResult.kt
@@ -0,0 +1,20 @@
+package mtmc.asm
+
+import mtmc.emulator.DebugInfo
+
+@JvmRecord
+data class AssemblyResult(
+  @JvmField val code: ByteArray,
+  val data: ByteArray,
+  val graphics: Array<ByteArray>,
+  @JvmField val debugInfo: DebugInfo?,
+  @JvmField val errors: MutableList<ASMError>
+) {
+  fun printErrors(): String {
+    val builder = StringBuilder("Errors:\n")
+    for (error in errors) {
+      builder.append("  Line " + error.token.line + ": " + error.error).append('\n')
+    }
+    return builder.toString()
+  }
+}
--- a/src/jvmMain/kotlin/mtmc/asm/HasLocation.kt
+++ b/src/jvmMain/kotlin/mtmc/asm/HasLocation.kt
@@ -0,0 +1,6 @@
+package mtmc.asm
+
+interface HasLocation {
+  var location: Int
+  var sizeInBytes: Int
+}
--- a/src/jvmMain/kotlin/mtmc/asm/data/Data.kt
+++ b/src/jvmMain/kotlin/mtmc/asm/data/Data.kt
@@ -0,0 +1,37 @@
+package mtmc.asm.data
+
+import mtmc.asm.ASMElement
+import mtmc.asm.Assembler
+import mtmc.tokenizer.MTMCToken
+
+class Data(labels: MutableList<MTMCToken>, lineNumber: Int) : ASMElement(labels, lineNumber) {
+  var valueToken: MTMCToken? = null
+  private var value: ByteArray = ByteArray(0)
+
+  override var sizeInBytes: Int
+    get() = value.size
+    set(value) {}
+
+  fun genData(dataBytes: ByteArray, assembler: Assembler) {
+    val offset = location - assembler.instructionsSizeInBytes
+    for (i in 0..<sizeInBytes) {
+      val dataByte = value[i]
+      dataBytes[offset + i] = dataByte
+    }
+  }
+
+  fun setValue(src: MTMCToken, value: ByteArray) {
+    this.valueToken = src
+    this.value = value
+  }
+
+  override fun toString(): String {
+    return "Data{" +
+        "value=" + value.contentToString() +
+        '}'
+  }
+
+  override fun addError(err: String) {
+    addError(labels.last(), err)
+  }
+}
--- a/src/jvmMain/kotlin/mtmc/asm/graphics/Graphic.kt
+++ b/src/jvmMain/kotlin/mtmc/asm/graphics/Graphic.kt
@@ -0,0 +1,51 @@
+package mtmc.asm.graphics
+
+import mtmc.asm.ASMElement
+import mtmc.emulator.MTMCDisplay.Companion.convertImage
+import mtmc.tokenizer.MTMCToken
+import java.io.ByteArrayOutputStream
+import java.io.File
+import java.io.FileNotFoundException
+import java.io.IOException
+import javax.imageio.ImageIO
+
+/**
+ *
+ * @author jbanes
+ */
+class Graphic(labels: MutableList<MTMCToken>, lineNumber: Int) : ASMElement(labels, lineNumber) {
+  private var filename: String? = null
+  var imageData: ByteArray = ByteArray(0)
+
+  fun setImage(filename: String) {
+    try {
+      var image = ImageIO.read(File(filename))
+      val buffer = ByteArrayOutputStream()
+
+      if (image.getWidth() > 1024 || image.getHeight() > 1024) {
+        addError(filename + " is too large. Maximum image size is 1024x1024")
+      }
+
+      image = convertImage(image)
+
+      ImageIO.write(image, "png", buffer)
+
+      this.filename = filename
+      this.imageData = buffer.toByteArray()
+    } catch (e: FileNotFoundException) {
+      e.printStackTrace()
+      addError("$filename not found")
+    } catch (e: IOException) {
+      e.printStackTrace()
+      addError(e.message ?: "error in Graphic") // TODO: Verify these messages are meaningful
+    }
+  }
+
+  override fun addError(err: String) {
+    addError(labels.last(), err)
+  }
+
+  override var sizeInBytes: Int
+    get() = 2
+    set(value) {}
+}
--- a/src/jvmMain/kotlin/mtmc/asm/instructions/ALUInstruction.kt
+++ b/src/jvmMain/kotlin/mtmc/asm/instructions/ALUInstruction.kt
@@ -0,0 +1,89 @@
+package mtmc.asm.instructions
+
+import mtmc.asm.Assembler
+import mtmc.emulator.Register.Companion.fromInteger
+import mtmc.emulator.Register.Companion.toInteger
+import mtmc.tokenizer.MTMCToken
+import mtmc.util.BinaryUtils
+import java.util.Locale
+
+class ALUInstruction(
+  type: InstructionType,
+  label: List<MTMCToken>,
+  instructionToken: MTMCToken
+) : Instruction(type, label, instructionToken) {
+  private var toToken: MTMCToken? = null
+  private var fromToken: MTMCToken? = null
+  private var immediateOp: MTMCToken? = null
+  private var value: MTMCToken? = null
+
+  fun setTo(to: MTMCToken) {
+    this.toToken = to
+  }
+
+  fun setFrom(from: MTMCToken?) {
+    this.fromToken = from
+  }
+
+  fun setImmediateValue(value: MTMCToken) {
+    this.value = value
+  }
+
+  fun setImmediateOp(immediateOp: MTMCToken) {
+    this.immediateOp = immediateOp
+  }
+
+  fun isImmediateOp(): Boolean {
+    return this.type == InstructionType.IMM
+  }
+
+  val isBinaryOp: Boolean
+    get() = !ALUOp.valueOf(instructionToken.stringValue.uppercase(Locale.getDefault())).isUnary
+
+  override fun genCode(output: ByteArray, assembler: Assembler) {
+    val opCode = ALUOp.toInteger(instructionToken.stringValue)
+    val to = toInteger(toToken!!.stringValue)
+    var from = 0
+    if (fromToken != null) {
+      from = toInteger(fromToken!!.stringValue)
+    }
+    output[location] = (16 or opCode).toByte()
+    if (this.isBinaryOp) {
+      output[location + 1] = (to shl 4 or from).toByte()
+    } else if (isImmediateOp()) {
+      val immediateValue = value!!.intValue()
+      val immediateOpValue = ALUOp.toInteger(immediateOp!!.stringValue)
+      output[location + 1] = (to shl 4 or immediateOpValue).toByte()
+      output[location + 2] = (immediateValue ushr 8).toByte()
+      output[location + 3] = immediateValue.toByte()
+    } else { // unary op
+      output[location + 1] = (to shl 4).toByte()
+    }
+  }
+
+  companion object {
+    @JvmStatic
+    fun disassemble(instruction: Short): String? {
+      if (BinaryUtils.getBits(16, 4, instruction).toInt() == 1) {
+        val builder = StringBuilder()
+        val opCode = BinaryUtils.getBits(12, 4, instruction)
+        val op = ALUOp.fromInt(opCode)
+        val aluOp = ALUOp.valueOf(op.uppercase(Locale.getDefault()))
+        if (aluOp == ALUOp.IMM) {
+          builder.append(op).append(" ")
+          builder.append(fromInteger(BinaryUtils.getBits(8, 4, instruction).toInt())).append(" ")
+          builder.append(ALUOp.fromInt(BinaryUtils.getBits(4, 4, instruction))).append(" ")
+        } else if (aluOp.isUnary) {
+          builder.append(op).append(" ")
+          builder.append(fromInteger(BinaryUtils.getBits(8, 4, instruction).toInt())).append(" ")
+        } else {
+          builder.append(op).append(" ")
+          builder.append(fromInteger(BinaryUtils.getBits(8, 4, instruction).toInt())).append(" ")
+          builder.append(fromInteger(BinaryUtils.getBits(4, 4, instruction).toInt())).append(" ")
+        }
+        return builder.toString()
+      }
+      return null
+    }
+  }
+}
--- a/src/jvmMain/kotlin/mtmc/asm/instructions/ALUOp.kt
+++ b/src/jvmMain/kotlin/mtmc/asm/instructions/ALUOp.kt
@@ -0,0 +1,44 @@
+package mtmc.asm.instructions
+
+import java.util.*
+
+enum class ALUOp(val opCode: Int, val isUnary: Boolean) {
+  ADD(0x0000, false),
+  SUB(0x0001, false),
+  MUL(0x0002, false),
+  DIV(0x0003, false),
+  MOD(0x0004, false),
+  AND(0x0005, false),
+  OR(0x0006, false),
+  XOR(0x0007, false),
+  SHL(0x0008, false),
+  SHR(0x0009, false),
+  MIN(0x000A, false),
+  MAX(0x000B, false),
+  NOT(0x000C, true),
+  LNOT(0x000D, true),
+  NEG(0x000E, true),
+  IMM(0x000F, true);
+
+  companion object {
+    @JvmStatic
+    fun toInteger(instruction: String): Int {
+      return valueOf(instruction.uppercase(Locale.getDefault())).opCode
+    }
+
+    @JvmStatic
+    fun fromInt(opCode: Short): String {
+      return entries[opCode.toInt()].name.lowercase(Locale.getDefault())
+    }
+
+    @JvmStatic
+    fun isALUOp(op: String): Boolean {
+      try {
+        val aluOp = valueOf(op.uppercase(Locale.getDefault()))
+        return true
+      } catch (e: IllegalArgumentException) {
+        return false
+      }
+    }
+  }
+}
--- a/src/jvmMain/kotlin/mtmc/asm/instructions/ErrorInstruction.kt
+++ b/src/jvmMain/kotlin/mtmc/asm/instructions/ErrorInstruction.kt
@@ -0,0 +1,23 @@
+package mtmc.asm.instructions
+
+import mtmc.asm.Assembler
+import mtmc.tokenizer.MTMCToken
+
+class ErrorInstruction(
+  labels: List<MTMCToken>,
+  instruction: MTMCToken,
+  error: String
+) : Instruction(
+  InstructionType.ERROR,
+  labels,
+  instruction
+) {
+
+  init {
+    addError(instruction, error)
+  }
+
+  override fun genCode(output: ByteArray, assembler: Assembler) {
+    // do nothing
+  }
+}
--- a/src/jvmMain/kotlin/mtmc/asm/instructions/Instruction.kt
+++ b/src/jvmMain/kotlin/mtmc/asm/instructions/Instruction.kt
@@ -0,0 +1,72 @@
+package mtmc.asm.instructions
+
+import mtmc.asm.ASMElement
+import mtmc.asm.Assembler
+import mtmc.asm.instructions.ALUInstruction.Companion.disassemble
+import mtmc.emulator.MonTanaMiniComputer.Companion.isDoubleWordInstruction
+import mtmc.tokenizer.MTMCToken
+
+abstract class Instruction(
+  @JvmField val type: InstructionType,
+  labels: List<MTMCToken>,
+  @JvmField val instructionToken: MTMCToken
+) : ASMElement(labels, instructionToken.line) {
+  open fun validateLabel(assembler: Assembler) {
+    // default does nothing
+  }
+
+  override fun addError(error: String) {
+    addError(instructionToken, error)
+  }
+
+  abstract fun genCode(output: ByteArray, assembler: Assembler)
+
+  override var sizeInBytes: Int = type.sizeInBytes
+    get() = type.sizeInBytes
+
+  companion object {
+    @JvmStatic
+    fun isInstruction(cmd: String): Boolean {
+      return InstructionType.fromString(cmd) != null
+    }
+
+    fun disassemble(instruction: Short, previousInstruction: Short): String {
+      if (isDoubleWordInstruction(previousInstruction)) {
+        return instruction.toInt().toString()
+      }
+      val misc = MiscInstruction.disassemble(instruction)
+      if (misc != null) {
+        return misc
+      }
+      val aluOp = disassemble(instruction)
+      if (aluOp != null) {
+        return aluOp
+      }
+      val stack = StackInstruction.disassemble(instruction)
+      if (stack != null) {
+        return stack
+      }
+      val test = TestInstruction.disassemble(instruction)
+      if (test != null) {
+        return test
+      }
+      val lsr = LoadStoreRegisterInstruction.disassemble(instruction)
+      if (lsr != null) {
+        return lsr
+      }
+      val ls = LoadStoreInstruction.disassemble(instruction)
+      if (ls != null) {
+        return ls
+      }
+      val jumpReg = JumpInstruction.disassemble(instruction)
+      if (jumpReg != null) {
+        return jumpReg
+      }
+      val jump = JumpInstruction.disassemble(instruction)
+      if (jump != null) {
+        return jump
+      }
+      return "<unknown>"
+    }
+  }
+}
--- a/src/jvmMain/kotlin/mtmc/asm/instructions/InstructionType.kt
+++ b/src/jvmMain/kotlin/mtmc/asm/instructions/InstructionType.kt
@@ -0,0 +1,98 @@
+package mtmc.asm.instructions
+
+import java.util.*
+
+enum class InstructionType @JvmOverloads constructor(
+  @JvmField val instructionClass: InstructionClass?,
+  val sizeInBytes: Int = 2
+) {
+  SYS(InstructionClass.MISC),
+  MOV(InstructionClass.MISC),
+  INC(InstructionClass.MISC),
+  DEC(InstructionClass.MISC),
+  SETI(InstructionClass.MISC),
+  NOP(InstructionClass.MISC),
+  MCP(InstructionClass.MISC, 4),
+  DEBUG(InstructionClass.MISC),
+  ADD(InstructionClass.ALU),
+  SUB(InstructionClass.ALU),
+  MUL(InstructionClass.ALU),
+  DIV(InstructionClass.ALU),
+  MOD(InstructionClass.ALU),
+  AND(InstructionClass.ALU),
+  OR(InstructionClass.ALU),
+  XOR(InstructionClass.ALU),
+  SHL(InstructionClass.ALU),
+  SHR(InstructionClass.ALU),
+  MIN(InstructionClass.ALU),
+  MAX(InstructionClass.ALU),
+  NOT(InstructionClass.ALU),
+  LNOT(InstructionClass.ALU),
+  NEG(InstructionClass.ALU),
+  IMM(InstructionClass.ALU, 4),
+  PUSH(InstructionClass.STACK),
+  POP(InstructionClass.STACK),
+  DUP(InstructionClass.STACK),
+  SWAP(InstructionClass.STACK),
+  DROP(InstructionClass.STACK),
+  OVER(InstructionClass.STACK),
+  ROT(InstructionClass.STACK),
+  SOP(InstructionClass.STACK),
+  PUSHI(InstructionClass.STACK, 4),
+  EQ(InstructionClass.TEST),
+  NEQ(InstructionClass.TEST),
+  GT(InstructionClass.TEST),
+  GTE(InstructionClass.TEST),
+  LT(InstructionClass.TEST),
+  LTE(InstructionClass.TEST),
+  EQI(InstructionClass.TEST),
+  NEQI(InstructionClass.TEST),
+  GTI(InstructionClass.TEST),
+  GTEI(InstructionClass.TEST),
+  LTI(InstructionClass.TEST),
+  LTEI(InstructionClass.TEST),
+  LWR(InstructionClass.LOAD_STORE_REGISTER),
+  LBR(InstructionClass.LOAD_STORE_REGISTER),
+  SWR(InstructionClass.LOAD_STORE_REGISTER),
+  SBR(InstructionClass.LOAD_STORE_REGISTER),
+  LW(InstructionClass.LOAD_STORE, 4),
+  LWO(InstructionClass.LOAD_STORE, 4),
+  LI(InstructionClass.LOAD_STORE, 4),
+  LB(InstructionClass.LOAD_STORE, 4),
+  LBO(InstructionClass.LOAD_STORE, 4),
+  SW(InstructionClass.LOAD_STORE, 4),
+  SWO(InstructionClass.LOAD_STORE, 4),
+  SB(InstructionClass.LOAD_STORE, 4),
+  SBO(InstructionClass.LOAD_STORE, 4),
+  JR(InstructionClass.JUMP_REGISTER),
+  J(InstructionClass.JUMP),
+  JZ(InstructionClass.JUMP),
+  JNZ(InstructionClass.JUMP),
+  JAL(InstructionClass.JUMP),
+  META(InstructionClass.MISC),
+  ERROR(InstructionClass.MISC),
+  ;
+
+
+  enum class InstructionClass {
+    MISC,
+    ALU,
+    STACK,
+    TEST,
+    LOAD_STORE_REGISTER,
+    LOAD_STORE,
+    JUMP_REGISTER,
+    JUMP
+  }
+
+  companion object {
+    @JvmStatic
+    fun fromString(string: String): InstructionType? {
+      try {
+        return valueOf(string.uppercase(Locale.getDefault()))
+      } catch (e: IllegalArgumentException) {
+        return null
+      }
+    }
+  }
+}
--- a/src/jvmMain/kotlin/mtmc/asm/instructions/JumpInstruction.kt
+++ b/src/jvmMain/kotlin/mtmc/asm/instructions/JumpInstruction.kt
@@ -0,0 +1,69 @@
+package mtmc.asm.instructions
+
+import mtmc.asm.Assembler
+import mtmc.tokenizer.MTMCToken
+import mtmc.util.BinaryUtils
+
+class JumpInstruction(
+  type: InstructionType,
+  label: List<MTMCToken>,
+  instructionToken: MTMCToken
+) : Instruction(type, label, instructionToken) {
+  private var addressToken: MTMCToken? = null
+
+  fun setAddressToken(addressToken: MTMCToken) {
+    this.addressToken = addressToken
+  }
+
+  override fun validateLabel(assembler: Assembler) {
+    if (addressToken!!.type == MTMCToken.TokenType.IDENTIFIER) {
+      if (!assembler.hasLabel(addressToken!!.stringValue)) {
+        addError("Unresolved label: " + addressToken!!.stringValue)
+      }
+    }
+  }
+
+  private fun resolveTargetAddress(assembler: Assembler): Int? {
+    if (addressToken!!.type == MTMCToken.TokenType.IDENTIFIER) {
+      return assembler.resolveLabel(addressToken!!.stringValue)
+    } else {
+      return addressToken!!.intValue()
+    }
+  }
+
+  override fun genCode(output: ByteArray, assembler: Assembler) {
+    var opcode = 0
+    when (type) {
+      InstructionType.J -> opcode = 12
+      InstructionType.JZ -> opcode = 13
+      InstructionType.JNZ -> opcode = 14
+      InstructionType.JAL -> opcode = 15
+      else -> println("Invalid instruction type")
+    }
+    val address = resolveTargetAddress(assembler)!!
+    output[location] = (opcode shl 4 or (address ushr 8)).toByte()
+    output[location + 1] = address.toByte()
+  }
+
+  companion object {
+    fun disassemble(instruction: Short): String? {
+      if (BinaryUtils.getBits(16, 2, instruction).toInt() == 3) {
+        val jumpType = BinaryUtils.getBits(14, 2, instruction)
+        val sb = StringBuilder()
+        if (jumpType.toInt() == 0) {
+          sb.append("j")
+        } else if (jumpType.toInt() == 1) {
+          sb.append("jz")
+        } else if (jumpType.toInt() == 2) {
+          sb.append("jnz")
+        } else if (jumpType.toInt() == 3) {
+          sb.append("jal")
+        }
+        val target = BinaryUtils.getBits(12, 12, instruction)
+        sb.append(" ").append(target.toInt())
+        return sb.toString()
+      }
+      return null
+    }
+  }
+}
--- a/src/jvmMain/kotlin/mtmc/asm/instructions/JumpRegisterInstruction.kt
+++ b/src/jvmMain/kotlin/mtmc/asm/instructions/JumpRegisterInstruction.kt
@@ -0,0 +1,37 @@
+package mtmc.asm.instructions
+
+import mtmc.asm.Assembler
+import mtmc.emulator.Register.Companion.fromInteger
+import mtmc.emulator.Register.Companion.toInteger
+import mtmc.tokenizer.MTMCToken
+import mtmc.util.BinaryUtils
+
+class JumpRegisterInstruction(
+  type: InstructionType,
+  label: List<MTMCToken>,
+  instructionToken: MTMCToken
+) : Instruction(type, label, instructionToken) {
+  private var register: MTMCToken? = null
+
+  fun setRegister(register: MTMCToken) {
+    this.register = register
+  }
+
+  public override fun genCode(output: ByteArray, assembler: Assembler) {
+    val opcode = 9
+    output[location] = (opcode shl 4).toByte()
+    val reg = toInteger(register!!.stringValue)
+    output[location + 1] = reg.toByte()
+  }
+
+  companion object {
+    fun disassemble(instruction: Short): String? {
+      if (BinaryUtils.getBits(16, 5, instruction).toInt() == 9) {
+        val reg = BinaryUtils.getBits(4, 4, instruction)
+        val sb = StringBuilder("jr")
+        sb.append(fromInteger(reg.toInt()))
+      }
+      return null
+    }
+  }
+}
--- a/src/jvmMain/kotlin/mtmc/asm/instructions/LoadStoreInstruction.kt
+++ b/src/jvmMain/kotlin/mtmc/asm/instructions/LoadStoreInstruction.kt
@@ -0,0 +1,115 @@
+package mtmc.asm.instructions
+
+import mtmc.asm.Assembler
+import mtmc.emulator.Register.Companion.fromInteger
+import mtmc.emulator.Register.Companion.toInteger
+import mtmc.tokenizer.MTMCToken
+import mtmc.util.BinaryUtils
+
+class LoadStoreInstruction(
+  type: InstructionType,
+  label: List<MTMCToken>,
+  instructionToken: MTMCToken
+) : Instruction(type, label, instructionToken) {
+  private var targetToken: MTMCToken? = null
+  private var offsetToken: MTMCToken? = null
+  private var value: MTMCToken? = null
+
+  fun setTargetToken(targetToken: MTMCToken) {
+    this.targetToken = targetToken
+  }
+
+  fun setOffsetToken(offsetToken: MTMCToken) {
+    this.offsetToken = offsetToken
+  }
+
+  fun setValue(value: MTMCToken) {
+    this.value = value
+  }
+
+  val isOffset: Boolean
+    get() = type.name.endsWith("O")
+
+  public override fun validateLabel(assembler: Assembler) {
+    if (value!!.type == MTMCToken.TokenType.IDENTIFIER) {
+      if (!assembler.hasLabel(value!!.stringValue)) {
+        addError("Unresolved label: " + value!!.stringValue)
+      }
+    }
+  }
+
+  private fun resolveValue(assembler: Assembler): Int? {
+    if (value!!.type == MTMCToken.TokenType.IDENTIFIER) {
+      return assembler.resolveLabel(value!!.stringValue)
+    } else {
+      return value!!.intValue()
+    }
+  }
+
+  override fun genCode(output: ByteArray, assembler: Assembler) {
+    val upperByte = when (type) {
+      InstructionType.LW -> 128
+      InstructionType.LWO -> 129
+      InstructionType.LB -> 130
+      InstructionType.LBO -> 131
+      InstructionType.SW -> 132
+      InstructionType.SWO -> 133
+      InstructionType.SB -> 134
+      InstructionType.SBO -> 135
+      InstructionType.LI -> 143
+      else -> 0
+    }
+
+    val target = toInteger(targetToken!!.stringValue)
+    output[location] = upperByte.toByte()
+
+    if (this.isOffset) {
+      val offsetReg = toInteger(offsetToken!!.stringValue)
+      output[location + 1] = (target shl 4 or offsetReg).toByte()
+    } else {
+      output[location + 1] = (target shl 4).toByte()
+    }
+
+    val numericValue = resolveValue(assembler)!!
+    output[location + 2] = (numericValue ushr 8).toByte()
+    output[location + 3] = numericValue.toByte()
+  }
+
+  companion object {
+    fun disassemble(instruction: Short): String? {
+      if (BinaryUtils.getBits(16, 4, instruction).toInt() == 8) {
+        val topNibble = BinaryUtils.getBits(12, 4, instruction)
+        val sb = StringBuilder()
+        if (topNibble.toInt() == 15) {
+          sb.append("li ")
+        } else if (topNibble.toInt() == 0) {
+          sb.append("lw ")
+        } else if (topNibble.toInt() == 1) {
+          sb.append("lwo ")
+        } else if (topNibble.toInt() == 2) {
+          sb.append("lb ")
+        } else if (topNibble.toInt() == 3) {
+          sb.append("lbo ")
+        } else if (topNibble.toInt() == 4) {
+          sb.append("sw ")
+        } else if (topNibble.toInt() == 5) {
+          sb.append("swo ")
+        } else if (topNibble.toInt() == 6) {
+          sb.append("sb ")
+        } else if (topNibble.toInt() == 7) {
+          sb.append("sbo ")
+        }
+        val target = BinaryUtils.getBits(8, 4, instruction)
+        val reg = fromInteger(target.toInt())
+        sb.append(reg)
+        if (topNibble.toInt() == 1 || topNibble.toInt() == 3 || topNibble.toInt() == 5 || topNibble.toInt() == 7) {
+          val offset = BinaryUtils.getBits(4, 4, instruction)
+          val offsetReg = fromInteger(offset.toInt())
+          sb.append(" ").append(offsetReg)
+        }
+        return sb.toString()
+      }
+      return null
+    }
+  }
+}
--- a/src/jvmMain/kotlin/mtmc/asm/instructions/LoadStoreRegisterInstruction.kt
+++ b/src/jvmMain/kotlin/mtmc/asm/instructions/LoadStoreRegisterInstruction.kt
@@ -0,0 +1,75 @@
+package mtmc.asm.instructions
+
+import mtmc.asm.Assembler
+import mtmc.emulator.Register
+import mtmc.emulator.Register.Companion.fromInteger
+import mtmc.emulator.Register.Companion.toInteger
+import mtmc.tokenizer.MTMCToken
+import mtmc.util.BinaryUtils
+
+class LoadStoreRegisterInstruction(
+  type: InstructionType,
+  label: List<MTMCToken>,
+  instructionToken: MTMCToken
+) : Instruction(type, label, instructionToken) {
+  private var targetToken: MTMCToken? = null
+  private var pointerToken: MTMCToken? = null
+  private var offsetToken: MTMCToken? = null
+
+  fun setTargetToken(targetToken: MTMCToken) {
+    this.targetToken = targetToken
+  }
+
+  fun setPointerToken(pointerToken: MTMCToken) {
+    this.pointerToken = pointerToken
+  }
+
+  fun setOffsetToken(offsetToken: MTMCToken?) {
+    this.offsetToken = offsetToken
+  }
+
+  override fun genCode(output: ByteArray, assembler: Assembler) {
+    var opcode = 0
+    when (type) {
+      InstructionType.LWR -> opcode = 4
+      InstructionType.LBR -> opcode = 5
+      InstructionType.SWR -> opcode = 6
+      InstructionType.SBR -> opcode = 7
+      else -> println("Invalid instruction type")
+    }
+    val target = toInteger(targetToken!!.stringValue)
+    val pointer = toInteger(pointerToken!!.stringValue)
+    var offset = Register.PC.ordinal
+    if (offsetToken != null) {
+      offset = toInteger(offsetToken!!.stringValue)
+    }
+    output[location] = (opcode shl 4 or target).toByte()
+    output[location + 1] = (pointer shl 4 or offset).toByte()
+  }
+
+  companion object {
+    fun disassemble(instruction: Short): String? {
+      if (BinaryUtils.getBits(16, 2, instruction).toInt() == 1) {
+        val builder = StringBuilder()
+        val type = BinaryUtils.getBits(14, 2, instruction)
+        if (type.toInt() == 0) {
+          builder.append("lwr ")
+        } else if (type.toInt() == 1) {
+          builder.append("lbr ")
+        } else if (type.toInt() == 2) {
+          builder.append("swr ")
+        } else if (type.toInt() == 3) {
+          builder.append("sbr ")
+        }
+        val srcDestReg = BinaryUtils.getBits(12, 4, instruction)
+        val addrReg = BinaryUtils.getBits(8, 4, instruction)
+        val offsetReg = BinaryUtils.getBits(4, 4, instruction)
+        builder.append(fromInteger(srcDestReg.toInt())).append(" ")
+        builder.append(fromInteger(addrReg.toInt())).append(" ")
+        builder.append(fromInteger(offsetReg.toInt()))
+        return builder.toString()
+      }
+      return null
+    }
+  }
+}
--- a/src/jvmMain/kotlin/mtmc/asm/instructions/MetaInstruction.kt
+++ b/src/jvmMain/kotlin/mtmc/asm/instructions/MetaInstruction.kt
@@ -0,0 +1,90 @@
+package mtmc.asm.instructions
+
+import mtmc.asm.Assembler
+import mtmc.tokenizer.MTMCToken
+
+class MetaInstruction(instruction: MTMCToken) :
+  Instruction(InstructionType.META, listOf(), instruction) {
+  private var originalFilePath: MTMCToken? = null
+  private var originaLineNumber: MTMCToken? = null
+  private var globalName: MTMCToken? = null
+  private var globalLocation: MTMCToken? = null
+  private var globalType: MTMCToken? = null
+  private var localName: MTMCToken? = null
+  private var localOffset: MTMCToken? = null
+  private var localType: MTMCToken? = null
+
+  override fun genCode(output: ByteArray, assembler: Assembler) {
+    // do nothing
+  }
+
+  val isFileDirective: Boolean
+    get() = "file" == this.instructionToken.stringValue
+
+  val isLineDirective: Boolean
+    get() = "line" == this.instructionToken.stringValue
+
+  val isGlobalDirective: Boolean
+    get() = "global" == this.instructionToken.stringValue
+
+  val isLocalDirective: Boolean
+    get() = "local" == this.instructionToken.stringValue
+
+  val isEndLocalDirective: Boolean
+    get() = "endlocal" == this.instructionToken.stringValue
+
+  fun setOriginalFilePath(path: MTMCToken) {
+    this.originalFilePath = path
+  }
+
+  fun setOriginalLineNumber(lineNumber: MTMCToken) {
+    this.originaLineNumber = lineNumber
+  }
+
+  val originalLineNumber: Int
+    get() = this.originaLineNumber!!.intValue()
+
+  fun setGlobalInfo(name: MTMCToken, location: MTMCToken, type: MTMCToken) {
+    this.globalName = name
+    this.globalLocation = location
+    this.globalType = type
+  }
+
+  fun setLocalInfo(name: MTMCToken, offset: MTMCToken, type: MTMCToken) {
+    this.localName = name
+    this.localOffset = offset
+    this.localType = type
+  }
+
+  fun setEndLocalInfo(name: MTMCToken) {
+    this.localName = name
+  }
+
+  fun getOriginalFilePath(): String? {
+    return this.originalFilePath!!.stringValue
+  }
+
+  fun getGlobalName(): String? {
+    return this.globalName!!.stringValue
+  }
+
+  fun getGlobalLocation(): Int {
+    return this.globalLocation!!.intValue()
+  }
+
+  fun getGlobalType(): String? {
+    return this.globalType!!.stringValue
+  }
+
+  fun getLocalName(): String? {
+    return this.localName!!.stringValue
+  }
+
+  fun getLocalOffset(): Int {
+    return this.localOffset!!.intValue()
+  }
+
+  fun getLocalType(): String? {
+    return this.localType!!.stringValue
+  }
+}
--- a/src/jvmMain/kotlin/mtmc/asm/instructions/MiscInstruction.kt
+++ b/src/jvmMain/kotlin/mtmc/asm/instructions/MiscInstruction.kt
@@ -0,0 +1,145 @@
+package mtmc.asm.instructions
+
+import mtmc.asm.Assembler
+import mtmc.emulator.Register.Companion.fromInteger
+import mtmc.emulator.Register.Companion.toInteger
+import mtmc.os.SysCall
+import mtmc.tokenizer.MTMCToken
+import mtmc.util.BinaryUtils
+
+class MiscInstruction(
+  type: InstructionType,
+  labels: List<MTMCToken>,
+  instructionToken: MTMCToken
+) : Instruction(type, labels, instructionToken) {
+  private var syscallType: MTMCToken? = null
+  private var fromRegister: MTMCToken? = null
+  private var toRegister: MTMCToken? = null
+  private var value: MTMCToken? = null
+
+  fun setSyscallType(type: MTMCToken) {
+    this.syscallType = type
+  }
+
+  fun setFrom(fromRegister: MTMCToken) {
+    this.fromRegister = fromRegister
+  }
+
+  fun setTo(toRegister: MTMCToken) {
+    this.toRegister = toRegister
+  }
+
+  fun setValue(value: MTMCToken?) {
+    this.value = value
+  }
+
+  override fun genCode(output: ByteArray, assembler: Assembler) {
+    if (type == InstructionType.SYS) {
+      output[location] = 0
+      output[location + 1] = SysCall.getValue(this.syscallType!!.stringValue)
+    } else if (type == InstructionType.MOV) {
+      val to = toInteger(toRegister!!.stringValue)
+      val from = toInteger(fromRegister!!.stringValue)
+      output[location] = 1
+      output[location + 1] = (to shl 4 or from).toByte()
+    } else if (type == InstructionType.INC) {
+      output[location] = 2
+      val to = toInteger(toRegister!!.stringValue)
+      var immediateVal = 1
+      if (value != null) {
+        immediateVal = value!!.intValue()
+      }
+      output[location + 1] = (to shl 4 or immediateVal).toByte()
+    } else if (type == InstructionType.DEC) {
+      output[location] = 3
+      val to = toInteger(toRegister!!.stringValue)
+      var immediateVal = 1
+      if (value != null) {
+        immediateVal = value!!.intValue()
+      }
+      output[location + 1] = (to shl 4 or immediateVal).toByte()
+    } else if (type == InstructionType.SETI) {
+      output[location] = 4
+      val to = toInteger(toRegister!!.stringValue)
+      val immediateVal = value!!.intValue()
+      output[location + 1] = (to shl 4 or immediateVal).toByte()
+    } else if (type == InstructionType.MCP) {
+      output[location] = 5
+      val from = toInteger(fromRegister!!.stringValue)
+      val to = toInteger(toRegister!!.stringValue)
+      val value = this.value!!.intValue()
+      output[location + 1] = (from shl 4 or to).toByte()
+      output[location + 2] = (value shl 8).toByte()
+      output[location + 3] = (value and 0xFF).toByte()
+    } else if (type == InstructionType.DEBUG) {
+      output[location] = 8
+      output[location + 1] = value!!.intValue().toByte()
+    } else if (type == InstructionType.NOP) {
+      output[location] = 15
+      output[location + 1] = 255.toByte()
+    }
+  }
+
+  companion object {
+    fun disassemble(instruction: Short): String? {
+      if (BinaryUtils.getBits(16, 4, instruction).toInt() == 0) {
+        val topNibble = BinaryUtils.getBits(12, 4, instruction)
+        if (topNibble.toInt() == 0) {
+          val builder = StringBuilder("sys ")
+          val bits = BinaryUtils.getBits(8, 8, instruction)
+          val name = SysCall.getString(bits.toByte())
+          builder.append(name)
+          return builder.toString()
+        } else if (topNibble.toInt() == 1) {
+          val builder = StringBuilder("mov ")
+          val to = BinaryUtils.getBits(8, 4, instruction)
+          val from = BinaryUtils.getBits(4, 4, instruction)
+          val toName = fromInteger(to.toInt())
+          builder.append(toName).append(" ")
+          val fromName = fromInteger(from.toInt())
+          builder.append(fromName)
+          return builder.toString()
+        } else if (topNibble.toInt() == 2) {
+          val builder = StringBuilder("inc ")
+          val to = BinaryUtils.getBits(8, 4, instruction)
+          val amount = BinaryUtils.getBits(4, 4, instruction)
+          val toName = fromInteger(to.toInt())
+          builder.append(toName).append(" ")
+          builder.append(amount.toInt())
+          return builder.toString()
+        } else if (topNibble.toInt() == 3) {
+          val builder = StringBuilder("dec ")
+          val to = BinaryUtils.getBits(8, 4, instruction)
+          val amount = BinaryUtils.getBits(4, 4, instruction)
+          val toName = fromInteger(to.toInt())
+          builder.append(toName).append(" ")
+          builder.append(amount.toInt())
+          return builder.toString()
+        } else if (topNibble.toInt() == 4) {
+          val builder = StringBuilder("seti ")
+          val to = BinaryUtils.getBits(8, 4, instruction)
+          val amount = BinaryUtils.getBits(4, 4, instruction)
+          val toName = fromInteger(to.toInt())
+          builder.append(toName).append(" ")
+          builder.append(amount.toInt())
+          return builder.toString()
+        } else if (topNibble.toInt() == 5) {
+          val from = BinaryUtils.getBits(8, 4, instruction)
+          val fromName = fromInteger(from.toInt())
+          val to = BinaryUtils.getBits(4, 4, instruction)
+          val toName = fromInteger(to.toInt())
+          return "mcp " + fromName + " " + toName
+        } else if (topNibble.toInt() == 8) {
+          val builder = StringBuilder("debug ")
+          val stringIndex = BinaryUtils.getBits(8, 8, instruction)
+          builder.append(stringIndex.toInt())
+          return builder.toString()
+        } else if (topNibble.toInt() == 15) {
+          val builder = StringBuilder("noop")
+          return builder.toString()
+        }
+      }
+      return null
+    }
+  }
+}
--- a/src/jvmMain/kotlin/mtmc/asm/instructions/StackInstruction.kt
+++ b/src/jvmMain/kotlin/mtmc/asm/instructions/StackInstruction.kt
@@ -0,0 +1,108 @@
+package mtmc.asm.instructions
+
+import mtmc.asm.Assembler
+import mtmc.asm.instructions.ALUOp.Companion.fromInt
+import mtmc.emulator.Register
+import mtmc.emulator.Register.Companion.fromInteger
+import mtmc.tokenizer.MTMCToken
+import mtmc.util.BinaryUtils
+
+class StackInstruction(
+  type: InstructionType,
+  label: List<MTMCToken>,
+  instructionToken: MTMCToken
+) : Instruction(type, label, instructionToken) {
+  private var targetToken: MTMCToken? = null
+  private var stackRegisterToken: MTMCToken? = null
+  private var aluOpToken: MTMCToken? = null
+  private var value: MTMCToken? = null
+
+  fun setTarget(target: MTMCToken) {
+    this.targetToken = target
+  }
+
+  fun setStackRegister(stackRegister: MTMCToken?) {
+    this.stackRegisterToken = stackRegister
+  }
+
+  fun setALUOp(aluOp: MTMCToken) {
+    this.aluOpToken = aluOp
+  }
+
+  fun setValue(value: MTMCToken) {
+    this.value = value
+  }
+
+  override fun genCode(output: ByteArray, assembler: Assembler) {
+    var stackReg = Register.SP.ordinal
+    if (stackRegisterToken != null) {
+      stackReg = Register.Companion.toInteger(stackRegisterToken!!.stringValue)
+    }
+    if (type == InstructionType.PUSH) {
+      val target = Register.Companion.toInteger(targetToken!!.stringValue)
+      output[location] = 32
+      output[location + 1] = (target shl 4 or stackReg).toByte()
+    } else if (type == InstructionType.POP) {
+      val target = Register.Companion.toInteger(targetToken!!.stringValue)
+      output[location] = 33
+      output[location + 1] = (target shl 4 or stackReg).toByte()
+    } else if (type == InstructionType.SOP) {
+      val aluOp = ALUOp.toInteger(aluOpToken!!.stringValue)
+      output[location] = 39
+      output[location + 1] = (aluOp shl 4 or stackReg).toByte()
+    } else if (type == InstructionType.PUSHI) {
+      val immediateValue = value!!.intValue()
+      output[location] = 47
+      output[location + 1] = stackReg.toByte()
+      output[location + 2] = (immediateValue ushr 8).toByte()
+      output[location + 3] = immediateValue.toByte()
+    } else {
+      val stackOp: Int
+      stackOp = when (type) {
+        InstructionType.DUP -> 34
+        InstructionType.SWAP -> 35
+        InstructionType.DROP -> 36
+        InstructionType.OVER -> 37
+        InstructionType.ROT -> 38
+        else -> 0
+      }
+      output[location] = stackOp.toByte()
+      output[location + 1] = stackReg.toByte()
+    }
+  }
+
+  companion object {
+    fun disassemble(instruction: Short): String? {
+      if (BinaryUtils.getBits(16, 4, instruction).toInt() == 2) {
+        val opCode = BinaryUtils.getBits(12, 4, instruction)
+        val stackReg = BinaryUtils.getBits(4, 4, instruction)
+        if (opCode.toInt() == 0) {
+          val sourceReg = BinaryUtils.getBits(8, 4, instruction)
+          return "push " + fromInteger(sourceReg.toInt()) + " " + fromInteger(stackReg.toInt())
+        }
+        if (opCode.toInt() == 1) {
+          val destReg = BinaryUtils.getBits(8, 4, instruction)
+          return "pop " + fromInteger(destReg.toInt()) + " " + fromInteger(stackReg.toInt())
+        }
+        if (opCode.toInt() == 2) {
+          return "dup " + fromInteger(stackReg.toInt())
+        } else if (opCode.toInt() == 3) {
+          return "swap " + fromInteger(stackReg.toInt())
+        } else if (opCode.toInt() == 4) {
+          return "drop " + fromInteger(stackReg.toInt())
+        } else if (opCode.toInt() == 5) {
+          return "over " + fromInteger(stackReg.toInt())
+        } else if (opCode.toInt() == 6) {
+          return "rot " + fromInteger(stackReg.toInt())
+        } else if (opCode.toInt() == 7) {
+          val aluOp = BinaryUtils.getBits(8, 4, instruction)
+          val op = fromInt(aluOp)
+          return "sop " + op + " " + fromInteger(stackReg.toInt())
+        } else if (opCode.toInt() == 15) {
+          return "pushi " + fromInteger(stackReg.toInt())
+        }
+      }
+      return null
+    }
+  }
+}
--- a/src/jvmMain/kotlin/mtmc/asm/instructions/TestInstruction.kt
+++ b/src/jvmMain/kotlin/mtmc/asm/instructions/TestInstruction.kt
@@ -0,0 +1,126 @@
+package mtmc.asm.instructions
+
+import mtmc.asm.Assembler
+import mtmc.emulator.Register.Companion.fromInteger
+import mtmc.emulator.Register.Companion.toInteger
+import mtmc.tokenizer.MTMCToken
+import mtmc.util.BinaryUtils
+
+class TestInstruction(
+  type: InstructionType,
+  label: List<MTMCToken>,
+  instructionToken: MTMCToken
+) : Instruction(type, label, instructionToken) {
+  private var first: MTMCToken? = null
+  private var second: MTMCToken? = null
+  private var value: MTMCToken? = null
+
+  fun setFirst(to: MTMCToken) {
+    this.first = to
+  }
+
+  fun setSecond(from: MTMCToken) {
+    this.second = from
+  }
+
+  fun setImmediateValue(value: MTMCToken) {
+    this.value = value
+  }
+
+  val isImmediate: Boolean
+    get() = type.name.endsWith("I")
+
+  override fun genCode(output: ByteArray, assembler: Assembler) {
+    val firstReg = toInteger(first!!.stringValue)
+    if (this.isImmediate) {
+      val upperByte = when (type) {
+        InstructionType.EQI -> 56
+        InstructionType.NEQI -> 57
+        InstructionType.GTI -> 58
+        InstructionType.GTEI -> 59
+        InstructionType.LTI -> 60
+        InstructionType.LTEI -> 61
+        else -> 0
+      }
+      val immediateValue = value!!.intValue()
+      output[location] = upperByte.toByte()
+      output[location + 1] = (firstReg shl 4 or immediateValue).toByte()
+    } else {
+      val upperByte = when (type) {
+        InstructionType.EQ -> 48
+        InstructionType.NEQ -> 49
+        InstructionType.GT -> 50
+        InstructionType.GTE -> 51
+        InstructionType.LT -> 52
+        InstructionType.LTE -> 53
+        else -> 0
+      }
+      val secondReg = toInteger(second!!.stringValue)
+      output[location] = upperByte.toByte()
+      output[location + 1] = (firstReg shl 4 or secondReg).toByte()
+    }
+  }
+
+  companion object {
+    fun disassemble(instruction: Short): String? {
+      if (BinaryUtils.getBits(16, 4, instruction).toInt() == 3) {
+        val sb = StringBuilder()
+        val opCode = BinaryUtils.getBits(12, 4, instruction)
+        val thirdNibble = BinaryUtils.getBits(8, 4, instruction)
+        val fourthNibble = BinaryUtils.getBits(4, 4, instruction)
+        if (opCode.toInt() == 0) {
+          sb.append("eq ")
+          sb.append(fromInteger(thirdNibble.toInt()))
+            .append(" ").append(fromInteger(fourthNibble.toInt()))
+        } else if (opCode.toInt() == 1) {
+          sb.append("neq ")
+          sb.append(fromInteger(thirdNibble.toInt()))
+            .append(" ").append(fromInteger(fourthNibble.toInt()))
+        } else if (opCode.toInt() == 2) {
+          sb.append("gt ")
+          sb.append(fromInteger(thirdNibble.toInt()))
+            .append(" ").append(fromInteger(fourthNibble.toInt()))
+        } else if (opCode.toInt() == 3) {
+          sb.append("gte ")
+          sb.append(fromInteger(thirdNibble.toInt()))
+            .append(" ").append(fromInteger(fourthNibble.toInt()))
+        } else if (opCode.toInt() == 4) {
+          sb.append("lt ")
+          sb.append(fromInteger(thirdNibble.toInt()))
+            .append(" ").append(fromInteger(fourthNibble.toInt()))
+        } else if (opCode.toInt() == 5) {
+          sb.append("lte ")
+          sb.append(fromInteger(thirdNibble.toInt()))
+            .append(" ").append(fromInteger(fourthNibble.toInt()))
+        }
+        if (opCode.toInt() == 8) {
+          sb.append("eqi ")
+          sb.append(fromInteger(thirdNibble.toInt()))
+            .append(" ").append(fourthNibble.toInt())
+        } else if (opCode.toInt() == 9) {
+          sb.append("neqi ")
+          sb.append(fromInteger(thirdNibble.toInt()))
+            .append(" ").append(fourthNibble.toInt())
+        } else if (opCode.toInt() == 10) {
+          sb.append("gti ")
+          sb.append(fromInteger(thirdNibble.toInt()))
+            .append(" ").append(fourthNibble.toInt())
+        } else if (opCode.toInt() == 11) {
+          sb.append("gtei ")
+          sb.append(fromInteger(thirdNibble.toInt()))
+            .append(" ").append(fourthNibble.toInt())
+        } else if (opCode.toInt() == 12) {
+          sb.append("lti ")
+          sb.append(fromInteger(thirdNibble.toInt()))
+            .append(" ").append(fourthNibble.toInt())
+        } else if (opCode.toInt() == 13) {
+          sb.append("ltei ")
+          sb.append(fromInteger(thirdNibble.toInt()))
+            .append(" ").append(fourthNibble.toInt())
+        }
+        return sb.toString()
+      }
+      return null
+    }
+  }
+}
--- a/src/jvmMain/kotlin/nl/astraeus/tmpl/db/Database.kt
+++ b/src/jvmMain/kotlin/nl/astraeus/tmpl/db/Database.kt
@@ -1,4 +1,4 @@
-package nl.astraeus.tmpl.db
+package mtmc.db

 import com.zaxxer.hikari.HikariConfig
 import com.zaxxer.hikari.HikariDataSource
--- a/src/jvmMain/kotlin/nl/astraeus/tmpl/db/Migrations.kt
+++ b/src/jvmMain/kotlin/nl/astraeus/tmpl/db/Migrations.kt
@@ -1,6 +1,6 @@
-package nl.astraeus.tmpl.db
+package mtmc.db

-import nl.astraeus.tmpl.log
+import mtmc.log
 import java.sql.Connection
 import java.sql.SQLException
 import java.sql.Timestamp
--- a/src/jvmMain/kotlin/mtmc/emulator/DebugInfo.kt
+++ b/src/jvmMain/kotlin/mtmc/emulator/DebugInfo.kt
@@ -0,0 +1,45 @@
+package mtmc.emulator
+
+import java.util.*
+import java.util.regex.Pattern
+
+@JvmRecord
+data class DebugInfo(
+  val debugStrings: MutableList<String>,
+  val assemblyFile: String?,
+  val assemblySource: String,
+  val assemblyLineNumbers: IntArray,
+  val originalFile: String,
+  val originalLineNumbers: IntArray,
+  val globals: Array<GlobalInfo>,
+  val locals: Array<Array<LocalInfo?>>
+) {
+  fun handleDebugString(debugIndex: Short, monTanaMiniComputer: MonTanaMiniComputer) {
+    val debugString = debugStrings!!.get(debugIndex.toInt())
+    val compile = Pattern.compile("(\\$[a-zA-Z][a-zA-Z0-9])")
+    val matcher = compile.matcher(debugString)
+    val formattedString = StringBuilder()
+    var start = 0
+    var end: Int
+    while (matcher.find()) {
+      val match = matcher.group().substring(1)
+      try {
+        end = matcher.start()
+        formattedString.append(debugString, start, end)
+        val register = Register.valueOf(match.uppercase(Locale.getDefault()))
+        formattedString.append(monTanaMiniComputer.getRegisterValue(register).toInt())
+        start = matcher.end()
+      } catch (e: Exception) {
+        formattedString.append(match)
+      }
+    }
+    formattedString.append(debugString.substring(start))
+    println("DEBUG[" + System.nanoTime() + "] : " + formattedString)
+  }
+
+  @JvmRecord
+  data class GlobalInfo(val name: String?, val location: Int, val type: String?)
+
+  @JvmRecord
+  data class LocalInfo(val name: String?, val offset: Int, val type: String?)
+}
--- a/src/jvmMain/kotlin/mtmc/emulator/MTMCClock.kt
+++ b/src/jvmMain/kotlin/mtmc/emulator/MTMCClock.kt
@@ -0,0 +1,71 @@
+package mtmc.emulator
+
+import mtmc.emulator.MonTanaMiniComputer.ComputerStatus
+import kotlin.math.max
+
+/**
+ *
+ * @author jbanes
+ */
+class MTMCClock
+  (private val computer: MonTanaMiniComputer) {
+  fun run() {
+    var instructions: Long = 0
+    var ips: Long = 0
+    var expected: Long = 0
+    var virtual: Long = 0
+
+    var startTime = System.currentTimeMillis()
+    var deltaStart: Long
+    var delta: Long
+
+    var speed: Long = 0
+    var pulse: Long
+    var ms: Long = 10
+
+    while (computer.getStatus() == ComputerStatus.EXECUTING) {
+      speed = max(computer.speed, 0).toLong()
+      pulse = (if (speed <= 0) 1000000 else max(speed / 100, 1))
+      ms = (if (pulse < 10) 1000 / speed else 10)
+
+      deltaStart = System.currentTimeMillis()
+      delta = ms - (System.currentTimeMillis() - deltaStart)
+
+
+      /* We've lost more than a second. Recalibrate. */
+      if ((expected - virtual) > pulse * 100) {
+        startTime = deltaStart
+        virtual = 0
+      }
+
+
+      /* Throttles to every 10ms, but "catches up" if we're behind */
+      if (delta > 0 && (expected - virtual) < pulse && speed != 0L) {
+        try {
+          Thread.sleep(delta)
+        } catch (e: InterruptedException) {
+        }
+      }
+
+      instructions += computer.pulse(pulse)
+
+      virtual += pulse
+      ips = (virtual * 1000) / max(1, System.currentTimeMillis() - startTime)
+      expected = (System.currentTimeMillis() - startTime) * speed / 1000
+    }
+
+    System.err.println("Executed " + instructions + " instructions at a rate of " + ips + " ips (speed = " + speed + ")")
+  }
+
+  fun step() {
+    computer.fetchAndExecute()
+    computer.fetchCurrentInstruction()
+    computer.notifyOfStepExecution()
+  }
+
+  fun back() {
+    computer.rewind()
+    computer.fetchCurrentInstruction()
+    computer.notifyOfStepExecution()
+  }
+}
--- a/src/jvmMain/kotlin/mtmc/emulator/MTMCConsole.kt
+++ b/src/jvmMain/kotlin/mtmc/emulator/MTMCConsole.kt
@@ -0,0 +1,131 @@
+package mtmc.emulator
+
+import mtmc.os.shell.Shell
+import mtmc.tokenizer.MTMCScanner
+import mtmc.tokenizer.MTMCToken
+import java.io.Console
+
+class MTMCConsole(private val computer: MonTanaMiniComputer) {
+  var mode: Mode = Mode.NON_INTERACTIVE
+  var sysConsole: Console? = null
+
+  // non-interactive data
+  private val output = StringBuffer()
+  private var shortValueSet = false
+  private var shortValue: Short = 0
+  private var stringValue: String? = null
+
+  // TODO invert so shell is driving and console is just IO
+  fun start() {
+    mode = Mode.INTERACTIVE
+    sysConsole = System.console()
+    Shell.printShellWelcome(computer)
+    while (true) {
+      val cmd = sysConsole!!.readLine("mtmc > ")
+      computer.oS.processCommand(cmd)
+    }
+  }
+
+  fun println(x: String) {
+    print(x)
+    print("\n")
+  }
+
+  fun print(x: String) {
+    output.append(x)
+    if (mode == Mode.INTERACTIVE) {
+      kotlin.io.print(x)
+    } else {
+      if (x.contains("\n")) {
+        computer.notifyOfConsoleUpdate()
+      } else {
+        computer.notifyOfConsolePrinting()
+      }
+    }
+  }
+
+  fun readChar(): Char {
+    if (mode == Mode.INTERACTIVE) {
+      val tokens = MTMCScanner(sysConsole!!.readLine(), "#").tokenize()
+      val token = tokens.first()
+      assert(token.type === MTMCToken.TokenType.CHAR)
+      return token.charValue()
+    } else {
+      this.shortValueSet = false
+      return Char(this.shortValue.toUShort())
+    }
+  }
+
+  fun readInt(): Short {
+    if (mode == Mode.INTERACTIVE) {
+      return sysConsole!!.readLine().toShort()
+    } else {
+      this.shortValueSet = false
+      return shortValue
+    }
+  }
+
+  fun hasShortValue(): Boolean {
+    return (mode == Mode.INTERACTIVE || shortValueSet)
+  }
+
+  fun setShortValue(shortValue: Short) {
+    this.shortValue = shortValue
+    this.shortValueSet = true
+  }
+
+  fun setCharValue(charValue: Char) {
+    this.shortValue = charValue.code.toShort()
+    this.shortValueSet = true
+  }
+
+  fun getOutput(): String {
+    return output.toString()
+  }
+
+  fun consumeLines(): String {
+    val index = output.lastIndexOf("\n")
+    val text = if (index >= 0) output.substring(0, index + 1) else ""
+
+    if (index >= 0) {
+      output.delete(0, index + 1)
+    }
+
+    return text
+  }
+
+  fun writeInt(value: Short) {
+    print(value.toString() + "")
+  }
+
+  fun setStringValue(stringValue: String?) {
+    this.stringValue = stringValue
+  }
+
+  fun readString(): String? {
+    if (mode == Mode.INTERACTIVE) {
+      return sysConsole!!.readLine()
+    } else {
+      val stringValue = this.stringValue
+      this.stringValue = null
+      return stringValue
+    }
+  }
+
+  fun hasReadString(): Boolean {
+    return (mode == Mode.INTERACTIVE || stringValue != null)
+  }
+
+  fun setReadString(stringValue: String?) {
+    this.stringValue = stringValue
+  }
+
+  fun resetOutput() {
+    output.delete(0, output.length)
+  }
+
+  enum class Mode {
+    NON_INTERACTIVE,
+    INTERACTIVE,
+  }
+}
--- a/src/jvmMain/kotlin/mtmc/emulator/MTMCDisplay.kt
+++ b/src/jvmMain/kotlin/mtmc/emulator/MTMCDisplay.kt
--- a/src/jvmMain/kotlin/mtmc/emulator/MTMCIO.kt
+++ b/src/jvmMain/kotlin/mtmc/emulator/MTMCIO.kt
@@ -0,0 +1,28 @@
+package mtmc.emulator
+
+import java.util.*
+
+class MTMCIO {
+  var value: Int = 0
+
+  internal enum class Buttons(val mask: Int) {
+    UP(128),
+    DOWN(64),
+    LEFT(32),
+    RIGHT(16),
+    START(8),
+    SELECT(4),
+    B(2),
+    A(1)
+  }
+
+  fun keyPressed(key: String) {
+    val button = Buttons.valueOf(key.uppercase(Locale.getDefault()))
+    value = value or button.mask
+  }
+
+  fun keyReleased(key: String) {
+    val button = Buttons.valueOf(key.uppercase(Locale.getDefault()))
+    value = value and button.mask.inv()
+  }
+}
--- a/src/jvmMain/kotlin/mtmc/emulator/MTMCObserver.kt
+++ b/src/jvmMain/kotlin/mtmc/emulator/MTMCObserver.kt
@@ -0,0 +1,33 @@
+package mtmc.emulator
+
+interface MTMCObserver {
+  fun consoleUpdated()
+
+  fun consolePrinting()
+
+  fun executionUpdated()
+
+  fun filesystemUpdated()
+
+  fun registerUpdated(register: Int, value: Int)
+
+  fun memoryUpdated(address: Int, value: Byte)
+
+  fun displayUpdated()
+
+  fun instructionFetched(instruction: Short)
+
+  fun beforeExecution(instruction: Short)
+
+  fun afterExecution(instruction: Short)
+
+  fun stepExecution()
+
+  fun computerReset()
+
+  fun requestCharacter()
+
+  fun requestInteger()
+
+  fun requestString()
+}
--- a/src/jvmMain/kotlin/mtmc/emulator/MonTanaMiniComputer.kt
+++ b/src/jvmMain/kotlin/mtmc/emulator/MonTanaMiniComputer.kt
--- a/src/jvmMain/kotlin/mtmc/emulator/Register.kt
+++ b/src/jvmMain/kotlin/mtmc/emulator/Register.kt
@@ -0,0 +1,76 @@
+package mtmc.emulator
+
+enum class Register {
+
+    //=== user-facing registers
+    T0,  // temp registers
+    T1,
+    T2,
+    T3,
+    T4,
+    T5,
+    A0,  // arg registers
+    A1,
+    A2,
+    A3,
+    RV,  // return value
+    RA,  // return address
+    FP, // frame pointer
+    SP, // stack pointer
+    BP, // break pointer
+    PC,
+
+    //=== non-user-facing registers
+    IR,    // instruction register
+    DR,    // data register
+    CB,    // code boundary
+    DB,    // data boundary
+    IO,    // I/O register
+    FLAGS; // flags register
+
+    companion object {
+        fun toInteger(reg: String): Int {
+            return valueOf(reg.uppercase()).ordinal
+        }
+
+        fun fromInteger(reg: Int): String {
+            return values()[reg].name.lowercase()
+        }
+
+        fun isWriteable(reg: Int): Boolean {
+            return reg in 0..15
+        }
+
+        fun isReadable(reg: Int): Boolean {
+            return reg in 0..15
+        }
+
+        private fun isTempRegister(reg: Int): Boolean {
+            return reg in 0..5
+        }
+
+        fun isWriteable(register: String): Boolean {
+            return try {
+                isWriteable(toInteger(register))
+            } catch (e: Exception) {
+                false
+            }
+        }
+
+        fun isReadable(register: String): Boolean {
+            return try {
+                isReadable(toInteger(register))
+            } catch (e: Exception) {
+                false
+            }
+        }
+
+        fun isTempRegister(register: String): Boolean {
+            return try {
+                isTempRegister(toInteger(register))
+            } catch (e: Exception) {
+                false
+            }
+        }
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/emulator/RewindStep.kt
+++ b/src/jvmMain/kotlin/mtmc/emulator/RewindStep.kt
@@ -0,0 +1,13 @@
+package mtmc.emulator
+
+class RewindStep {
+  var subSteps: MutableList<Runnable?> = ArrayList<Runnable?>()
+
+  fun rewind() {
+    subSteps.reversed().forEach({ obj: Runnable? -> obj!!.run() })
+  }
+
+  fun addSubStep(subStep: Runnable?) {
+    subSteps.add(subStep)
+  }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/CompilationException.java
+++ b/src/jvmMain/kotlin/mtmc/lang/CompilationException.java
@@ -0,0 +1,19 @@
+package mtmc.lang;
+
+public class CompilationException extends Exception {
+    protected Span span;
+
+    public CompilationException(String message, Span span) {
+        super(message);
+        this.span = span;
+    }
+
+    public CompilationException(CompilationException parent, String message) {
+        super(message, parent);
+        this.span = parent.span;
+    }
+
+    public Span getSpan() {
+        return span;
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/Language.java
+++ b/src/jvmMain/kotlin/mtmc/lang/Language.java
@@ -0,0 +1,7 @@
+package mtmc.lang;
+
+import mtmc.os.exec.Executable;
+
+public interface Language {
+    Executable compileExecutable(String filename, String source) throws ParseException, CompilationException;
+}
--- a/src/jvmMain/kotlin/mtmc/lang/Location.java
+++ b/src/jvmMain/kotlin/mtmc/lang/Location.java
@@ -0,0 +1,55 @@
+package mtmc.lang;
+
+public record Location(int index) {
+
+    public static int[] getLineNos(String source, int... indices) {
+        int[] out = new int[indices.length];
+        int index = 0, line = 1;
+        while (index < source.length()) {
+            for (int i = 0; i < indices.length; i++) {
+                if (indices[i] == index) {
+                    out[i] = line;
+                }
+            }
+
+            int cp = source.charAt(index);
+            if (cp == '\n') {
+                line += 1;
+            }
+            index += Character.charCount(cp);
+        }
+        return out;
+    }
+
+    public LineInfo getLineInfo(String source) {
+        int index = 0, lineStart = 0;
+        int lineno = 1;
+        int column = 1;
+        while (index < source.length()) {
+            if (index == this.index) {
+                break;
+            }
+            int cp = source.charAt(index);
+
+            if (cp == '\n') {
+                lineno += 1;
+                lineStart = index + 1;
+            } else {
+                column += 1;
+            }
+
+            index += Character.charCount(cp);
+        }
+
+        while (index < source.length()) {
+            int cp = source.charAt(index);
+            index += Character.charCount(cp);
+            if (cp == '\n') break;
+        }
+        String line = source.substring(lineStart, index);
+
+        return new LineInfo(lineno, column, line);
+    }
+
+    public record LineInfo(int lineno, int column, String line) {}
+}
--- a/src/jvmMain/kotlin/mtmc/lang/ParseException.java
+++ b/src/jvmMain/kotlin/mtmc/lang/ParseException.java
@@ -0,0 +1,43 @@
+package mtmc.lang;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+
+public class ParseException extends Exception {
+    public final List<Message> messages;
+
+    public ParseException(Message message, Message ...rest) {
+        var messages = new ArrayList<Message>(1 + rest.length);
+        messages.add(message);
+        messages.addAll(Arrays.asList(rest));
+        this.messages = Collections.unmodifiableList(messages);
+    }
+
+    public ParseException(ParseException parent, Message message, Message ...rest) {
+        var messages = new ArrayList<Message>( 1 + rest.length + parent.messages.size());
+        messages.add(message);
+        messages.addAll(Arrays.asList(rest));
+        messages.addAll(parent.messages);
+        this.messages = Collections.unmodifiableList(messages);
+    }
+
+    public record Message(Span span, String message) {
+        public Message(Token token, String message) {
+            this(Span.of(token), message);
+        }
+
+        public Token start() {
+            return span.start();
+        }
+
+        public Token end() {
+            return span.end();
+        }
+    }
+
+    public String report(String source) {
+        return "TODO: I ain't no snitch";
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/Span.java
+++ b/src/jvmMain/kotlin/mtmc/lang/Span.java
@@ -0,0 +1,17 @@
+package mtmc.lang;
+
+public record Span(Token start, Token end) {
+
+    public static Span of(Token token) {
+        return new Span(token, token);
+    }
+
+    public static Span of(Token start, Token end) {
+        return new Span(start, end);
+    }
+
+    public boolean isOnSingleLine(String source) {
+        int[] lines = Location.getLineNos(source, start.start(), end.end());
+        return lines[0] == lines[1];
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/Token.java
+++ b/src/jvmMain/kotlin/mtmc/lang/Token.java
@@ -0,0 +1,15 @@
+package mtmc.lang;
+
+public interface Token {
+    Location getStart();
+    Location getEnd();
+    String getContent();
+
+    default int start() {
+        return getStart().index();
+    }
+
+    default int end() {
+        return getEnd().index();
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/SeaCompiler.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/SeaCompiler.java
--- a/src/jvmMain/kotlin/mtmc/lang/sea/SeaLanguage.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/SeaLanguage.java
@@ -0,0 +1,47 @@
+package mtmc.lang.sea;
+
+import mtmc.lang.CompilationException;
+import mtmc.lang.Language;
+import mtmc.lang.ParseException;
+import mtmc.lang.sea.ast.Error;
+import mtmc.lang.sea.ast.Unit;
+import mtmc.os.exec.Executable;
+
+public class SeaLanguage implements Language {
+    @Override
+    public Executable compileExecutable(String filename, String source) throws ParseException, CompilationException  {
+        var tokens = Token.tokenize(source);
+        var parser = new SeaParser(filename, source, tokens);
+        Unit program = parser.parseUnit();
+        var errors = program.collectErrors();
+        if (!errors.isEmpty()) {
+            StringBuilder sb = new StringBuilder();
+            for (Error error : errors) {
+                reportError(source, sb, error.exception());
+            }
+            throw new RuntimeException(sb.toString());
+        }
+
+
+        var compiler = new SeaCompiler(program);
+        return compiler.compile();
+    }
+
+    private static void reportError(String src, StringBuilder sb, ParseException e) {
+        sb.append("Error:\n");
+        for (var msg : e.messages) {
+            var lo = Token.getLineAndOffset(src, msg.start().start());
+            int lineNo = lo[0];
+            int column = lo[1];
+            var line = Token.getLineFor(src, msg.start().start());
+            String prefix = "  %03d:%03d | ".formatted(lineNo, column);
+            String info = " ".repeat(prefix.length() - 2) + "| ";
+            sb.append(info).append(msg.message()).append('\n');
+            sb.append(prefix).append(line).append('\n');
+            sb
+                    .repeat(' ', prefix.length() + column - 1)
+                    .repeat('^', Math.max(1, msg.end().end() - msg.start().start()));
+            sb.append("\n\n");
+        }
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/SeaParser.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/SeaParser.java
--- a/src/jvmMain/kotlin/mtmc/lang/sea/SeaType.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/SeaType.java
@@ -0,0 +1,231 @@
+package mtmc.lang.sea;
+
+import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.Map;
+
+public sealed interface SeaType {
+    default int size() {
+        if (this == CHAR) return 2;
+        if (this == INT) return 2;
+        if (this == VOID) return 0;
+        if (this instanceof Pointer) return 2;
+        if (this instanceof Struct struct) {
+            int size = 0;
+            for (Map.Entry<String, SeaType> fieldSet : struct.fields.entrySet()) {
+                SeaType type = fieldSet.getValue();
+                size += type.size();
+            }
+            return size;
+        }
+        throw new IllegalStateException("sizeof " + getClass().getName() + " is undefined");
+    }
+
+    default boolean isArithmetic() {
+        return this == CHAR || this == INT;
+    }
+
+    default boolean isIntegral() {
+        return this == CHAR || this == INT || this instanceof Pointer;
+    }
+
+    default boolean isStructure() {
+        return this instanceof Struct;
+    }
+
+    default boolean isInt() {
+        return this == INT;
+    }
+
+    default boolean isChar() {
+        return this == CHAR;
+    }
+
+    default boolean isVoid() {
+        return this == VOID;
+    }
+
+    default boolean isAnIntegralPointer() {
+        return this instanceof Pointer(SeaType component) && component.isIntegral();
+    }
+
+    default boolean isAPointerToAnInt() {
+        return this instanceof Pointer(SeaType component) && component.isInt();
+    }
+
+    default boolean isAPointerTo(SeaType inner) {
+        return this instanceof Pointer(SeaType it) && it.equals(inner);
+    }
+
+    default boolean isAPointer() {
+        return this instanceof Pointer;
+    }
+
+    default boolean isFunc() {
+        return this instanceof Func;
+    }
+
+    default SeaType componentType() {
+        return ((Pointer) this).component;
+    }
+
+    default SeaType resultType() {
+        return ((Func) this).result();
+    }
+
+    default void checkConversionTo(SeaType other) throws ConversionError {
+        if (this.isVoid() || other.isVoid()) throw new ConversionError(this, other, "void is not assignable to void");
+        if (this.isArithmetic() && other.isArithmetic()) return;
+        if (this.isAPointer() && other.isAPointer()) return;
+        if (this instanceof Initializer initializer && other instanceof Struct s) {
+            // this is kinda complex
+            // the way this should work is we process named assignments and then based on the last
+            // index of the named assignments, we start putting in values
+            // the challenge here is that the blob may have too many values or may initialize them improperly
+            if (initializer.values.size() != s.fields.size()) {
+                throw new ConversionError(this, other, "initializer has too many or too few values");
+            }
+
+            int i = 0;
+            for (Map.Entry<String, SeaType> entry : s.fields.entrySet()) {
+                var name = entry.getKey();
+                var ty = entry.getValue();
+                var valueTy = initializer.values.get(i);
+
+                try {
+                    valueTy.checkConversionTo(ty);
+                } catch (ConversionError error) {
+                    throw new ConversionError(ty, valueTy,
+                            "value cannot be assigned to " + ty.repr() + " for '" + name + "'", error);
+                }
+
+                i += 1;
+            }
+            return;
+        }
+        if (!this.equals(other)) {
+            throw new ConversionError(this, other, this.repr() + " is not convertible to " + other.repr());
+        }
+    }
+
+    class ConversionError extends Exception {
+        public final SeaType fromType, toType;
+
+        private ConversionError(SeaType fromType, SeaType toType, String message) {
+            super(message);
+            this.fromType = fromType;
+            this.toType = toType;
+        }
+
+        private ConversionError(SeaType fromType, SeaType toType, String message, ConversionError parent) {
+            super(message, parent);
+            this.fromType = fromType;
+            this.toType = toType;
+        }
+    }
+
+    default boolean isCastableTo(SeaType target) {
+        if (target.isVoid()) return true;
+        if (this.isAPointer() && target.isInt()) return true;
+        if (this.isArithmetic() && target.isArithmetic()) return true;
+        return this.equals(target);
+    }
+
+    default String repr() {
+        if (this instanceof Pointer p) {
+            if (p.baseType() instanceof Func(List<SeaType> params, boolean isVararg, SeaType result)) {
+                var s = new StringBuilder();
+                s.append(result.repr()).append("(*");
+                var x = p.component;
+                while (x instanceof Pointer p2) {
+                    x = p2.component;
+                    s.append("*");
+                }
+                s.append(")(");
+                int i = 0;
+                for (var param : params) {
+                    if (i > 0) s.append(", ");
+                    s.append(param.repr());
+                    i = i + 1;
+                }
+                s.append(")");
+                return s.toString();
+            } else {
+                return p.component.repr() + "*";
+            }
+        }
+        if (this == CHAR) return "char";
+        if (this == INT) return "int";
+        if (this == VOID) return "void";
+        if (this instanceof Func(List<SeaType> params, boolean isVararg, SeaType result)) {
+            var s = new StringBuilder();
+            s.append(result.repr());
+            s.append("(");
+            int i = 0;
+            for (var param : params) {
+                if (i > 0) s.append(", ");
+                s.append(param.repr());
+                i = i + 1;
+            }
+            s.append(")");
+            return s.toString();
+        }
+        if (this instanceof Initializer(List<SeaType> values)) {
+            var s = new StringBuilder();
+            s.append("{");
+            for (int i = 0; i < values.size(); i++) {
+                if (i > 0) s.append(", ");
+                s.append(values.get(i).repr());
+            }
+            s.append("}");
+            return s.toString();
+        }
+        if (this instanceof Struct s) {
+            return "struct " + s.name;
+        }
+        throw new UnsupportedOperationException("unknown type " + this);
+    }
+
+    SeaType CHAR = new Primitive("char");
+    SeaType INT = new Primitive("int");
+    SeaType VOID = new Primitive("void");
+
+    record Pointer(SeaType component) implements SeaType {
+        SeaType baseType() {
+            var ty = component;
+            while (ty instanceof Pointer(SeaType c)) {
+                ty = c;
+            }
+            return ty;
+        }
+    }
+
+    final class Primitive implements SeaType {
+        // this is purely for debug info lmfao
+        public final String name;
+
+        private Primitive(String name) {
+            this.name = name;
+        }
+
+        @Override
+        public String toString() {
+            return name;
+        }
+    }
+
+    record Func(List<SeaType> params, boolean isVararg, SeaType result) implements SeaType {
+        public Func(List<SeaType> params, SeaType result) {
+            this(params, false, result);
+        }
+    }
+
+    record Struct(String name, LinkedHashMap<String, SeaType> fields) implements SeaType {
+        public SeaType field(String name) {
+            return fields.get(name);
+        }
+    }
+
+    record Initializer(List<SeaType> values) implements SeaType {
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/Symbol.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/Symbol.java
@@ -0,0 +1,59 @@
+package mtmc.lang.sea;
+
+import mtmc.lang.sea.ast.DeclarationFunc;
+import mtmc.lang.sea.ast.DeclarationVar;
+import mtmc.lang.sea.ast.StatementVar;
+import mtmc.lang.sea.ast.TypeDeclaration;
+
+public class Symbol {
+    public final String name;
+    public final SeaType type;
+    public final TypeDeclaration typeDecl;
+    public final boolean isParam, isGlobal;
+
+    public Symbol(DeclarationFunc.Param param) {
+        this.name = param.name.content();
+        this.type = param.type.type();
+        this.typeDecl = null;
+        this.isParam = true;
+        this.isGlobal = false;
+    }
+
+    public Symbol(DeclarationVar decl) {
+        this.name = decl.name();
+        this.type = decl.type.type();
+        this.typeDecl = null;
+        this.isParam = false;
+        this.isGlobal = true;
+    }
+
+    public Symbol(StatementVar stmt) {
+        this.name = stmt.name();
+        this.type = stmt.type.type();
+        this.typeDecl = null;
+        this.isParam = false;
+        this.isGlobal = false;
+    }
+
+    public Symbol(DeclarationFunc func) {
+        this.name = func.name.content();
+        this.type = func.type();
+        this.typeDecl = null;
+        this.isParam = false;
+        this.isGlobal = true;
+    }
+
+    public Symbol(TypeDeclaration declaration) {
+        this.name = declaration.name();
+        this.type = null;
+        this.typeDecl = declaration;
+        this.isParam = false;
+        this.isGlobal = false;
+    }
+
+    public boolean isAddressable() {
+        if (this.typeDecl != null) throw new IllegalStateException("cannot address non-data symbol");
+        if (this.isParam) return false; // parameters are not addressable!
+        return true;
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/Token.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/Token.java
@@ -0,0 +1,426 @@
+package mtmc.lang.sea;
+
+import mtmc.lang.Location;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Objects;
+
+public record Token(
+        Type type,
+        @NotNull
+        String content,
+        int start,
+        int end
+) implements mtmc.lang.Token {
+    public static final Token SOF = new Token(Type.SOF, "", 0, 0);
+    public static final Token EOF = new Token(Type.EOF, "", Integer.MAX_VALUE, Integer.MAX_VALUE);
+
+    public enum Type {
+        // Special
+        LIT_INT(null),
+        LIT_STR(null),
+        LIT_CHAR(null),
+        LIT_IDENT(null),
+        KW_TYPEDEF("typedef"),
+        KW_STRUCT("struct"),
+        KW_IF("if"),
+        KW_ELSE("else"),
+        KW_FOR("for"),
+        KW_WHILE("while"),
+        KW_DO("do"),
+        KW_GOTO("goto"),
+        KW_CONTINUE("continue"),
+        KW_BREAK("break"),
+        KW_RETURN("return"),
+        KW_SIZEOF("sizeof"),
+        KW_INT("int"),
+        KW_CHAR("char"),
+        KW_VOID("void"),
+        SOF(null),
+        EOF(null),
+
+        // Groups
+        LEFT_PAREN("("),
+        RIGHT_PAREN(")"),
+        LEFT_BRACKET("["),
+        RIGHT_BRACKET("]"),
+        LEFT_BRACE("{"),
+        RIGHT_BRACE("}"),
+
+        // Simple Punct
+        DOT3("..."),
+        DOT("."),
+        SEMICOLON(";"),
+        COMMA(","),
+        COLON(":"),
+        TILDE("~"),
+        QUESTION("?"),
+
+        PLUS2("++"),
+        PLUS_EQ("+="),
+        PLUS("+"),
+
+        DASH2("--"),
+        DASH_EQ("-="),
+        ARROW("->"),
+        DASH("-"),
+
+        STAR_EQ("*="),
+        STAR("*"),
+
+        SLASH_EQ("/="),
+        SLASH("/"),
+
+        PERCENT_EQ("%="),
+        PERCENT("%"),
+
+        AMPERSAND2("&&"),
+        AMPERSAND_EQ("&="),
+        AMPERSAND("&"),
+
+        BAR2("||"),
+        BAR_EQ("|="),
+        BAR("|"),
+
+        CARET("^"),
+        CARET_EQ("^="),
+
+        LEFT_ARROW2_EQ("<<="),
+        LEFT_ARROW2("<<"),
+        LEFT_ARROW_EQ("<="),
+        LEFT_ARROW("<"),
+
+        RIGHT_ARROW2_EQ(">>="),
+        RIGHT_ARROW2(">>"),
+        RIGHT_ARROW_EQ(">="),
+        RIGHT_ARROW(">"),
+
+        EQUAL2("=="),
+        EQUAL("="),
+
+        BANG_EQ("!="),
+        BANG("!");
+
+        public final String lex;
+
+        public static final Type[] PUNCT;
+        static {
+            List<Type> list = new ArrayList<>();
+            for (Type t : Type.values()) {
+                if (t.lex != null) {
+                    list.add(t);
+                }
+            }
+            PUNCT = list.toArray(new Type[0]);
+        }
+
+        public static final Type[] KEYWORDS;
+        static {
+            List<Type> list = new ArrayList<>();
+            for (Type t : Type.values()) {
+                if (t.name().startsWith("KW_")) {
+                    list.add(t);
+                }
+            }
+            KEYWORDS = list.toArray(new Type[0]);
+        }
+
+        Type(String lex) {
+            this.lex = lex;
+        }
+    }
+
+    public static int[] getLineAndOffset(String src, int index) {
+        int line = 1;
+        int column = 1;
+        for (int i = 0; i < index && i < src.length(); i++) {
+            char c = src.charAt(i);
+            if (c == '\n') {
+                line = line + 1;
+                column = 1;
+            } else {
+                column = column + 1;
+            }
+        }
+        return new int[]{line, column};
+    }
+
+    public static String getLineFor(String src, int index) {
+        int start = 0;
+        for (int i = Math.min(index, src.length() - 1); i >= 0; i--) {
+            if (src.charAt(i) == '\n') {
+                start = i + 1;
+                break;
+            }
+        }
+
+        int end = src.length();
+        for (int i = index; i < src.length(); i++) {
+            if (src.charAt(i) == '\n') {
+                break;
+            }
+            end = i + 1;
+        }
+        return src.substring(start, end);
+    }
+
+    public static String highlight(String src, int start, int end) {
+        var s = getLineAndOffset(src, start);
+        var e = getLineAndOffset(src, end);
+
+        int lineStart;
+        if (s[0] != e[0]) {
+            lineStart = 0;
+        } else {
+            lineStart = s[1] - 1;
+        }
+
+        int lineEnd = e[1] - 1;
+
+        String line = getLineFor(src, end);
+
+        StringBuilder result = new StringBuilder();
+        int off = 0;
+
+        if (lineStart > 10) {
+            result.append("... ");
+            off += 4;
+            result.append(line.substring(lineStart, lineEnd));
+        } else {
+            result.append(line.substring(0, lineEnd));
+        }
+
+        result.append('\n');
+        result.repeat(' ', off + lineStart);
+        if (start == Integer.MAX_VALUE) {
+            result.append("^ (at EOL)");
+        } else {
+            result.repeat('^', lineEnd - lineStart);
+            result.append(" (here)");
+        }
+        return result.toString();
+    }
+
+    public static List<Token> tokenize(String src) throws TokenizeException {
+        List<Token> tokens = new ArrayList<>();
+        int offset = 0;
+        do {
+            Token token = tokenizeOne(src, offset);
+            if (token == null) break;
+            tokens.add(token);
+            offset = token.end();
+        } while (true);
+        return tokens;
+    }
+
+    private static boolean match(String str, int start, String token) {
+        if (str == null) return false;
+        if (str.length() - start < token.length()) return false;
+        for (int i = 0; i < token.length(); i++) {
+            char c = str.charAt(start + i);
+            char d = token.charAt(i);
+            if (c != d) return false;
+        }
+        return true;
+    }
+
+    private static boolean match(String str, int start, char c) {
+        if (str == null) return false;
+        if (str.length() - start < Character.charCount(c)) return false;
+        return str.charAt(start) == c;
+    }
+
+    public static Token tokenizeOne(String src, int offset) throws TokenizeException {
+        while (offset < src.length()) {
+            if (Character.isWhitespace(src.charAt(offset))) {
+                offset += Character.charCount(src.charAt(offset));
+            } else if (match(src, offset, "//")) {
+                offset += 2;
+                while (offset < src.length()) {
+                    char c = src.charAt(offset);
+                    offset += Character.charCount(c);
+                    if (c == '\n') {
+                        break;
+                    }
+                }
+            } else if (match(src, offset, "/*")) {
+                offset += 2;
+                while (offset < src.length()) {
+                    if (match(src, offset, "*/")) {
+                        offset += 2;
+                        break;
+                    } else {
+                        offset += Character.charCount(src.charAt(offset));
+                    }
+                }
+            } else {
+                break;
+            }
+        }
+        if (offset >= src.length()) return null;
+
+        int start = offset;
+        Type type;
+        String content = null;
+
+        char c = src.charAt(offset);
+        if (Character.isDigit(c)) {
+            do {
+                offset += Character.charCount(src.charAt(offset));
+            } while (offset < src.length() && Character.isDigit(src.charAt(offset)));
+            content = src.substring(start, offset);
+            type = Type.LIT_INT;
+        } else if (Character.isLetter(c) || c == '_') {
+            do {
+                offset += Character.charCount(src.charAt(offset));
+            } while (offset < src.length() && (Character.isLetter(src.charAt(offset)) || Character.isDigit(src.charAt(offset)) || src.charAt(offset) == '_'));
+            content = src.substring(start, offset);
+            type = Type.LIT_IDENT;
+            for (var ty : Type.KEYWORDS) {
+                if (content.equals(ty.lex)) {
+                    type = ty;
+                    break;
+                }
+            }
+        } else if (c == '\'') {
+            offset += Character.charCount(c);
+            char d = src.charAt(offset);
+            offset += Character.charCount(d);
+            if (d == '\\') {
+                if (offset >= src.length()) throw new TokenizeException("invalid character escape " + d, start, offset);
+                d = src.charAt(offset);
+                offset += Character.charCount(d);
+                content = switch (d) {
+                    case 'n':
+                        yield "\n";
+                    case 'r':
+                        yield "\r";
+                    case 't':
+                        yield "\t";
+                    case '\\':
+                        yield "\\";
+                    case '\'':
+                        yield "'";
+                    case '"':
+                        yield "\"";
+                    case '?':
+                        yield "?";
+                    default:
+                        throw new TokenizeException("invalid character escape " + d, start, offset);
+                };
+            } else {
+                content = String.valueOf(d);
+            }
+
+            if (offset >= src.length() || src.charAt(offset) != '\'') {
+                throw new TokenizeException("unterminated character literal", start, offset);
+            }
+            offset += Character.charCount('\'');
+            type = Type.LIT_CHAR;
+        } else if (c == '"') {
+            offset += Character.charCount(src.charAt(offset));
+            StringBuilder sb = new StringBuilder();
+            while (offset < src.length() && src.charAt(offset) != '"') {
+                char d = src.charAt(offset);
+                offset += Character.charCount(d);
+
+                if (d == '\\') {
+                    d = src.charAt(offset);
+                    offset += Character.charCount(d);
+                    char s = switch (d) {
+                        case 'n':
+                            yield '\n';
+                        case 'r':
+                            yield '\r';
+                        case 't':
+                            yield '\t';
+                        case '\\':
+                            yield '\\';
+                        case '\'':
+                            yield '\'';
+                        case '"':
+                            yield '"';
+                        case '?':
+                            yield '?';
+                        default:
+                            throw new TokenizeException("invalid string escape " + d, start, offset);
+                    };
+                    sb.append(s);
+                } else if (d == '\n') {
+                    break;
+                } else {
+                    sb.append(d);
+                }
+            }
+
+            if (offset >= src.length() || src.charAt(offset) != '"') {
+                throw new TokenizeException("unterminated string literal", start, offset);
+            }
+
+            content = sb.toString();
+            offset += Character.charCount('\"');
+            type = Type.LIT_STR;
+        } else {
+            type = null;
+            for (Type t : Type.PUNCT) {
+                if (match(src, start, t.lex)) {
+                    type = t;
+                    content = t.lex;
+                    offset += t.lex.length();
+                    break;
+                }
+            }
+
+            if (type == null) {
+                throw new TokenizeException("unexpected character '" + src.charAt(start) + "'", start, offset);
+            }
+        }
+
+        Objects.requireNonNull(content);
+        return new Token(type, content, start, offset);
+    }
+
+    public static class TokenizeException extends IllegalArgumentException {
+        public final int start, end;
+
+        public TokenizeException(String msg, int start, int end) {
+            super(msg);
+            this.start = start;
+            this.end = end;
+        }
+
+        @Override
+        public String toString() {
+            return "TokenizeException at " + start + ":" + end + ", " + getLocalizedMessage();
+        }
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (o instanceof String s) return Objects.equals(content, s);
+        if (!(o instanceof Token token)) return false;
+        return end == token.end && start == token.start && Objects.equals(content, token.content) && type == token.type;
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(type, content, start, end);
+    }
+
+    @Override
+    public Location getStart() {
+        return new Location(start);
+    }
+
+    @Override
+    public Location getEnd() {
+        return new Location(end);
+    }
+
+    @Override
+    public String getContent() {
+        return content();
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/Ast.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/Ast.java
@@ -0,0 +1,139 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.Span;
+import mtmc.lang.sea.Token;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.stream.Stream;
+
+public sealed abstract class Ast permits Declaration, DeclarationFunc.Param, DeclarationStruct.Field, Expression, Statement, TypeExpr, Unit {
+    public final Token start, end;
+
+    public Ast(Token start, Token end) {
+        this.start = start;
+        this.end = end;
+    }
+
+    public Span span() {
+        return Span.of(start, end);
+    }
+
+    public Stream<Ast> getChildren() {
+        return switch (this) {
+            case DeclarationFunc declarationFunc -> {
+                Stream<Ast> out = Stream.of(declarationFunc.returnType);
+                out = Stream.concat(out, declarationFunc.params.params().stream());
+                if (declarationFunc.body != null) {
+                    out = Stream.concat(out, Stream.of(declarationFunc.body));
+                }
+                yield out;
+            }
+            case DeclarationSyntaxError ignored -> Stream.empty();
+            case DeclarationTypedef declarationTypedef -> Stream.of(declarationTypedef.type);
+            case DeclarationVar declarationVar -> {
+                Stream<Ast> out = Stream.of(declarationVar.type);
+                if (declarationVar.initializer != null) {
+                    out = Stream.concat(out, Stream.of(declarationVar.initializer));
+                }
+                yield out;
+            }
+            case DeclarationStruct struct -> struct.fields.stream().map(x -> x);
+            case DeclarationStruct.Field field -> Stream.of(field.type);
+            case DeclarationFunc.Param param -> Stream.of(param.type);
+            case ExpressionAccess expressionAccess -> Stream.of(expressionAccess.value);
+            case ExpressionBin expressionBin -> Stream.of(expressionBin.lhs, expressionBin.rhs);
+            case ExpressionCall expressionCall -> {
+                Stream<Ast> out = Stream.of(expressionCall.functor);
+                out = Stream.concat(out, expressionCall.args.stream());
+                yield out;
+            }
+            case ExpressionInitializer init -> init.values.stream().map(x -> x);
+            case ExpressionCast expressionCast -> Stream.of(expressionCast.type, expressionCast.value);
+            case ExpressionChar ignored -> Stream.empty();
+            case ExpressionIdent ignored -> Stream.empty();
+            case ExpressionIndex expressionIndex -> Stream.of(expressionIndex.array, expressionIndex.index);
+            case ExpressionInteger ignored -> Stream.empty();
+            case ExpressionParens expressionParens -> Stream.of(expressionParens.inner);
+            case ExpressionPostfix expressionPostfix -> Stream.of(expressionPostfix.inner);
+            case ExpressionPrefix expressionPrefix -> Stream.of(expressionPrefix.inner);
+            case ExpressionString ignored -> Stream.empty();
+            case ExpressionTypeError typeError -> Stream.of(typeError.inner);
+            case ExpressionSyntaxError expressionSyntaxError -> {
+                if (expressionSyntaxError.child != null) {
+                    yield Stream.of(expressionSyntaxError.child);
+                } else {
+                    yield Stream.empty();
+                }
+            }
+            case ExpressionTernary expressionTernary -> Stream.of(
+                    expressionTernary.cond,
+                    expressionTernary.then,
+                    expressionTernary.otherwise
+            );
+            case StatementBlock statementBlock -> statementBlock.statements.stream().map(x -> x);
+            case StatementBreak ignored -> Stream.empty();
+            case StatementContinue ignored -> Stream.empty();
+            case StatementDoWhile statementDoWhile -> Stream.of(statementDoWhile.body, statementDoWhile.condition);
+            case StatementExpression statementExpression -> Stream.of(statementExpression.expression);
+            case StatementFor statementFor -> {
+                Stream<Ast> out = Stream.empty();
+                if (statementFor.initExpression != null) {
+                    out = Stream.concat(out, Stream.of(statementFor.initExpression));
+                } else if (statementFor.initStatement != null) {
+                    out = Stream.concat(out, Stream.of(statementFor.initStatement));
+                }
+                if (statementFor.condition != null) {
+                    out = Stream.concat(out, Stream.of(statementFor.condition));
+                }
+                if (statementFor.inc != null) {
+                    out = Stream.concat(out, Stream.of(statementFor.inc));
+                }
+                out = Stream.concat(out, Stream.of(statementFor.body));
+                yield out;
+            }
+            case StatementGoto ignored -> Stream.empty();
+            case StatementIf statementIf -> {
+                Stream<Ast> out = Stream.of(statementIf.condition, statementIf.body);
+                if (statementIf.elseBody != null) out = Stream.concat(out, Stream.of(statementIf.elseBody));
+                yield out;
+            }
+            case StatementReturn statementReturn -> {
+                if (statementReturn.value == null) {
+                    yield Stream.empty();
+                } else {
+                    yield Stream.of(statementReturn.value);
+                }
+            }
+            case StatementSyntaxError ignored -> Stream.empty();
+            case StatementVar statementVar -> {
+                Stream<Ast> out = Stream.of(statementVar.type);
+                if (statementVar.initValue != null) {
+                    out = Stream.concat(out, Stream.of(statementVar.initValue));
+                }
+                yield out;
+            }
+            case StatementWhile statementWhile -> Stream.of(statementWhile.condition, statementWhile.body);
+            case TypeExprArray typeExprArray -> Stream.of(typeExprArray.inner);
+            case TypeExprChar ignored -> Stream.empty();
+            case TypeExprInt ignored -> Stream.empty();
+            case TypeExprRef ignored -> Stream.empty();
+            case TypeExprVoid ignored -> Stream.empty();
+            case TypePointer ignored -> Stream.empty();
+            case Unit unit -> unit.declarations.stream().map(x -> x);
+        };
+    }
+
+    public List<Error> collectErrors() {
+        var errors = new ArrayList<Error>();
+        collectErrors(errors);
+        return errors;
+    }
+
+    public void collectErrors(List<Error> errors) {
+        if (this instanceof Error e) {
+            errors.add(e);
+        }
+        getChildren().forEach(child -> child.collectErrors(errors));
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/Declaration.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/Declaration.java
@@ -0,0 +1,9 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.Token;
+
+public abstract sealed class Declaration extends Ast permits DeclarationFunc, DeclarationStruct, DeclarationSyntaxError, DeclarationTypedef, DeclarationVar {
+    public Declaration(Token start, Token end) {
+        super(start, end);
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/DeclarationFunc.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/DeclarationFunc.java
@@ -0,0 +1,59 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.SeaType;
+import mtmc.lang.sea.Token;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public final class DeclarationFunc extends Declaration {
+    public final TypeExpr returnType;
+    public final Token name;
+    public final ParamList params;
+    public final StatementBlock body;
+
+    public DeclarationFunc(TypeExpr returnType, Token name, ParamList paramList, StatementBlock body, Token end) {
+        super(returnType.start, end);
+        this.returnType = returnType;
+        this.name = name;
+        this.params = paramList;
+        this.body = body;
+    }
+
+    public static final class Param extends Ast {
+        public final TypeExpr type;
+        public final Token name;
+
+        public Param(TypeExpr type, Token name) {
+            super(type.start, name.end() < type.end.end() ? type.end : name);
+            this.type = type;
+            this.name = name;
+        }
+    }
+
+    private SeaType.Func type;
+    public SeaType.Func type() {
+        if (type == null) {
+            var paramTypes = new ArrayList<SeaType>(params.size());
+            for (Param param : params.params) {
+                paramTypes.add(param.type.type());
+            }
+            type = new SeaType.Func(
+                    paramTypes,
+                    params.isVararg,
+                    returnType.type()
+            );
+        }
+        return type;
+    }
+
+    public record ParamList(List<Param> params, boolean isVararg) {
+        public int size() {
+            return params.size();
+        }
+
+        public SeaType getParamType(int i) {
+            return params.get(i).type.type();
+        }
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/DeclarationStruct.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/DeclarationStruct.java
@@ -0,0 +1,54 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.SeaType;
+import mtmc.lang.sea.Token;
+
+import java.util.LinkedHashMap;
+import java.util.List;
+
+public final class DeclarationStruct extends Declaration implements TypeDeclaration {
+    public final Token name;
+    public final List<Field> fields;
+
+    public DeclarationStruct(Token start, Token name, List<Field> fields, Token end) {
+        super(start, end);
+        this.name = name;
+        this.fields = List.copyOf(fields);
+    }
+
+    public String name() {
+        return name.content();
+    }
+
+    private SeaType type;
+    @Override
+    public SeaType type() {
+        if (type == null) {
+            var fields = new LinkedHashMap<String, SeaType>();
+            for (var field : this.fields) {
+                fields.put(field.name(), field.type());
+            }
+            type = new SeaType.Struct(name(), fields);
+        }
+        return type;
+    }
+
+    public static final class Field extends Ast {
+        public final TypeExpr type;
+        public final Token name;
+
+        public Field(TypeExpr type, Token name) {
+            super(type.start, name);
+            this.type = type;
+            this.name = name;
+        }
+
+        public String name() {
+            return name.content();
+        }
+
+        public SeaType type() {
+            return type.type();
+        }
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/DeclarationSyntaxError.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/DeclarationSyntaxError.java
@@ -0,0 +1,18 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.ParseException;
+import mtmc.lang.sea.Token;
+
+public final class DeclarationSyntaxError extends Declaration implements SyntaxError {
+    public final ParseException exception;
+
+    public DeclarationSyntaxError(Token token, ParseException parseException) {
+        super(token, token);
+        this.exception = parseException;
+    }
+
+    @Override
+    public ParseException exception() {
+        return exception;
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/DeclarationTypedef.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/DeclarationTypedef.java
@@ -0,0 +1,26 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.SeaType;
+import mtmc.lang.sea.Token;
+
+public final class DeclarationTypedef extends Declaration implements TypeDeclaration {
+    public final TypeExpr type;
+    public final Token name;
+
+
+    public DeclarationTypedef(Token start, TypeExpr type, Token name, Token end) {
+        super(start, type.end);
+        this.type = type;
+        this.name = name;
+    }
+
+    @Override
+    public String name() {
+        return name.content();
+    }
+
+    @Override
+    public SeaType type() {
+        return type.type();
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/DeclarationVar.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/DeclarationVar.java
@@ -0,0 +1,20 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.Token;
+
+public final class DeclarationVar extends Declaration {
+    public final TypeExpr type;
+    public final Token name;
+    public final Expression initializer;
+
+    public DeclarationVar(TypeExpr type, Token name, Expression initializer) {
+        super(type.start, initializer == null ? name : initializer.end);
+        this.type = type;
+        this.name = name;
+        this.initializer = initializer;
+    }
+
+    public String name() {
+        return this.name.content();
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/Error.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/Error.java
@@ -0,0 +1,7 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.ParseException;
+
+public interface Error {
+    ParseException exception();
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/Expression.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/Expression.java
@@ -0,0 +1,23 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.SeaType;
+import mtmc.lang.sea.Token;
+
+import java.util.Objects;
+
+public sealed abstract class Expression extends Ast permits ExpressionAccess, ExpressionBin, ExpressionCall, ExpressionCast, ExpressionChar, ExpressionIdent, ExpressionIndex, ExpressionInitializer, ExpressionInteger, ExpressionParens, ExpressionPostfix, ExpressionPrefix, ExpressionString, ExpressionSyntaxError, ExpressionTernary, ExpressionTypeError {
+    private final SeaType type;
+    public Expression(Token start, Token end, SeaType type) {
+        super(start, end);
+        this.type = Objects.requireNonNull(type, "'type' cannot be null");
+    }
+
+    public SeaType type() {
+        return type;
+    }
+
+    public enum ValueKind {
+        Addressable,
+        Immediate
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionAccess.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionAccess.java
@@ -0,0 +1,17 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.SeaType;
+import mtmc.lang.sea.Token;
+
+public final class ExpressionAccess extends Expression {
+    public final Expression value;
+    public final Token access;
+    public final Token prop;
+
+    public ExpressionAccess(Expression value, Token access, Token prop, SeaType type) {
+        super(value.start, prop, type);
+        this.value = value;
+        this.access = access;
+        this.prop = prop;
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionBin.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionBin.java
@@ -0,0 +1,21 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.SeaType;
+import mtmc.lang.sea.Token;
+
+public final class ExpressionBin extends Expression {
+    public final Expression lhs;
+    public final Token op;
+    public final Expression rhs;
+
+    public ExpressionBin(Expression lhs, Token op, Expression rhs, SeaType type) {
+        super(lhs.start, rhs.end, type);
+        this.lhs = lhs;
+        this.op = op;
+        this.rhs = rhs;
+    }
+
+    public String op() {
+        return op.content();
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionCall.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionCall.java
@@ -0,0 +1,17 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.SeaType;
+import mtmc.lang.sea.Token;
+
+import java.util.List;
+
+public final class ExpressionCall extends Expression {
+    public final Expression functor;
+    public final List<Expression> args;
+
+    public ExpressionCall(Expression functor, List<Expression> args, Token end, SeaType type) {
+        super(functor.start, end, type);
+        this.functor = functor;
+        this.args = args;
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionCast.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionCast.java
@@ -0,0 +1,14 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.Token;
+
+public final class ExpressionCast extends Expression {
+    public final TypeExpr type;
+    public final Expression value;
+
+    public ExpressionCast(Token start, TypeExpr type, Expression value) {
+        super(start, value.end, type.type());
+        this.type = type;
+        this.value = value;
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionChar.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionChar.java
@@ -0,0 +1,14 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.SeaType;
+import mtmc.lang.sea.Token;
+
+public final class ExpressionChar extends Expression {
+    public ExpressionChar(Token token) {
+        super(token, token, SeaType.CHAR);
+    }
+
+    public Character content() {
+        return start.content().charAt(0);
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionIdent.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionIdent.java
@@ -0,0 +1,17 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.SeaType;
+import mtmc.lang.sea.Token;
+
+public final class ExpressionIdent extends Expression {
+    public final boolean isAddressable;
+
+    public ExpressionIdent(Token token, SeaType type, boolean isAddressable) {
+        super(token, token, type);
+        this.isAddressable = isAddressable;
+    }
+
+    public String name() {
+        return start.content();
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionIndex.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionIndex.java
@@ -0,0 +1,14 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.SeaType;
+import mtmc.lang.sea.Token;
+
+public final class ExpressionIndex extends Expression {
+    public final Expression array, index;
+
+    public ExpressionIndex(Expression array, Expression index, Token end, SeaType type) {
+        super(array.start, end, type);
+        this.array = array;
+        this.index = index;
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionInitializer.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionInitializer.java
@@ -0,0 +1,27 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.SeaType;
+import mtmc.lang.sea.Token;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public final class ExpressionInitializer extends Expression {
+    public final List<Expression> values;
+
+    private static SeaType.Initializer blobType(List<Expression> values) {
+        var types = new ArrayList<SeaType>();
+
+        for (var value : values) {
+            types.add(value.type());
+        }
+
+        return new SeaType.Initializer(types);
+    }
+
+    public ExpressionInitializer(Token start, List<Expression> values, Token end) {
+        super(start, end, blobType(values));
+        this.values = List.copyOf(values);
+    }
+
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionInteger.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionInteger.java
@@ -0,0 +1,13 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.SeaType;
+import mtmc.lang.sea.Token;
+
+public final class ExpressionInteger extends Expression {
+    public final int value;
+
+    public ExpressionInteger(Token start) {
+        super(start, start, SeaType.INT);
+        this.value = Integer.parseInt(start.content());
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionParens.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionParens.java
@@ -0,0 +1,12 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.Token;
+
+public final class ExpressionParens extends Expression {
+    public final Expression inner;
+
+    public ExpressionParens(Token start, Expression inner, Token end) {
+        super(start, end, inner.type());
+        this.inner = inner;
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionPostfix.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionPostfix.java
@@ -0,0 +1,17 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.SeaType;
+import mtmc.lang.sea.Token;
+
+public final class ExpressionPostfix extends Expression {
+    public Expression inner;
+
+    public ExpressionPostfix(Expression lhs, Token op, SeaType type) {
+        super(lhs.start, op, type);
+        this.inner = lhs;
+    }
+
+    public String op() {
+        return end.content();
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionPrefix.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionPrefix.java
@@ -0,0 +1,17 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.SeaType;
+import mtmc.lang.sea.Token;
+
+public final class ExpressionPrefix extends Expression {
+    public final Expression inner;
+
+    public ExpressionPrefix(Token operator, Expression rhs, SeaType type) {
+        super(operator, rhs.end, type);
+        this.inner = rhs;
+    }
+
+    public String op() {
+        return start.content();
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionString.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionString.java
@@ -0,0 +1,18 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.SeaType;
+import mtmc.lang.sea.Token;
+
+public final class ExpressionString extends Expression {
+    public ExpressionString(Token token) {
+        super(token, token, new SeaType.Pointer(SeaType.CHAR));
+    }
+
+    public byte[] getBytes() {
+        return start.content().getBytes();
+    }
+
+    public String content() {
+        return start.content();
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionSyntaxError.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionSyntaxError.java
@@ -0,0 +1,27 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.ParseException;
+import mtmc.lang.sea.SeaType;
+import mtmc.lang.sea.Token;
+import org.jetbrains.annotations.Nullable;
+
+public final class ExpressionSyntaxError extends Expression implements SyntaxError {
+    @Nullable
+    public final Expression child;
+    public final ParseException exception;
+
+    public ExpressionSyntaxError(Token token, String message) {
+        this(null, token, message);
+    }
+
+    public ExpressionSyntaxError(@Nullable Expression child, Token token, String message) {
+        super(child == null ? token : child.start, token, SeaType.INT);
+        this.child = child;
+        this.exception = new ParseException(new ParseException.Message(token, message));
+    }
+
+    @Override
+    public ParseException exception() {
+        return exception;
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionTernary.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionTernary.java
@@ -0,0 +1,16 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.SeaType;
+
+public final class ExpressionTernary extends Expression {
+    public final Expression cond;
+    public final Expression then;
+    public final Expression otherwise;
+
+    public ExpressionTernary(Expression cond, Expression then, Expression otherwise, SeaType type) {
+        super(cond.start, otherwise.end, type);
+        this.cond = cond;
+        this.then = then;
+        this.otherwise = otherwise;
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionTypeError.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/ExpressionTypeError.java
@@ -0,0 +1,20 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.ParseException;
+
+public final class ExpressionTypeError extends Expression implements Error {
+    public final Expression inner;
+    public final ParseException exception;
+
+    public ExpressionTypeError(Expression inner, String message) {
+        super(inner.start, inner.end, inner.type());
+        this.inner = inner;
+        this.exception = new ParseException(new ParseException.Message(inner.span(), message));
+    }
+
+
+    @Override
+    public ParseException exception() {
+        return exception;
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/Statement.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/Statement.java
@@ -0,0 +1,25 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.ParseException;
+import mtmc.lang.sea.Token;
+
+public abstract sealed class Statement extends Ast permits StatementBlock, StatementBreak, StatementContinue, StatementDoWhile, StatementExpression, StatementFor, StatementGoto, StatementIf, StatementReturn, StatementSyntaxError, StatementVar, StatementWhile
+{
+    private Token labelAnchor = null;
+
+    public Statement(Token start, Token end) {
+        super(start, end);
+    }
+
+    public void setLabelAnchor(Token labelAnchor) throws ParseException {
+        if (labelAnchor == null) return;
+        if (this.labelAnchor != null) {
+            throw new ParseException(new ParseException.Message(labelAnchor, "this statement has been labeled twice!!"));
+        }
+        this.labelAnchor = labelAnchor;
+    }
+
+    public Token getLabelAnchor() {
+        return labelAnchor;
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/StatementBlock.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/StatementBlock.java
@@ -0,0 +1,14 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.Token;
+
+import java.util.List;
+
+public final class StatementBlock extends Statement {
+    public final List<Statement> statements;
+
+    public StatementBlock(Token start, List<Statement> children, Token end) {
+        super(start, end);
+        this.statements = List.copyOf(children);
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/StatementBreak.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/StatementBreak.java
@@ -0,0 +1,9 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.Token;
+
+public final class StatementBreak extends Statement {
+    public StatementBreak(Token breakToken) {
+        super(breakToken, breakToken);
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/StatementContinue.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/StatementContinue.java
@@ -0,0 +1,9 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.Token;
+
+public final class StatementContinue extends Statement {
+    public StatementContinue(Token continueToken) {
+        super(continueToken, continueToken);
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/StatementDoWhile.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/StatementDoWhile.java
@@ -0,0 +1,14 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.Token;
+
+public final class StatementDoWhile extends Statement {
+    public final Statement body;
+    public final Expression condition;
+
+    public StatementDoWhile(Token start, Statement body, Expression condition, Token end) {
+        super(start, end);
+        this.body = body;
+        this.condition = condition;
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/StatementExpression.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/StatementExpression.java
@@ -0,0 +1,10 @@
+package mtmc.lang.sea.ast;
+
+public final class StatementExpression extends Statement {
+    public final Expression expression;
+
+    public StatementExpression(Expression expression) {
+        super(expression.start, expression.end);
+        this.expression = expression;
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/StatementFor.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/StatementFor.java
@@ -0,0 +1,20 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.Token;
+
+public final class StatementFor extends Statement {
+    public final Expression initExpression;
+    public final StatementVar initStatement;
+    public final Expression condition;
+    public final Expression inc;
+    public final Statement body;
+
+    public StatementFor(Token start, Expression initExpression, StatementVar initStatement, Expression condition, Expression inc, Statement body) {
+        super(start, body.end);
+        this.initExpression = initExpression;
+        this.initStatement = initStatement;
+        this.condition = condition;
+        this.inc = inc;
+        this.body = body;
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/StatementGoto.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/StatementGoto.java
@@ -0,0 +1,12 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.Token;
+
+public final class StatementGoto extends Statement {
+    public final Token label;
+
+    public StatementGoto(Token start, Token label) {
+        super(start, label);
+        this.label = label;
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/StatementIf.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/StatementIf.java
@@ -0,0 +1,16 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.Token;
+
+public final class StatementIf extends Statement {
+    public final Expression condition;
+    public final Statement body;
+    public final Statement elseBody;
+
+    public StatementIf(Token start, Expression condition, Statement body, Statement elseBody) {
+        super(start, elseBody == null ? body.end : elseBody.end);
+        this.condition = condition;
+        this.body = body;
+        this.elseBody = elseBody;
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/StatementReturn.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/StatementReturn.java
@@ -0,0 +1,12 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.Token;
+
+public final class StatementReturn extends Statement {
+    public final Expression value;
+
+    public StatementReturn(Token start, Expression value) {
+        super(start, value == null ? start : value.end);
+        this.value = value;
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/StatementSyntaxError.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/StatementSyntaxError.java
@@ -0,0 +1,18 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.ParseException;
+import mtmc.lang.sea.Token;
+
+public final class StatementSyntaxError extends Statement implements SyntaxError {
+    public final ParseException exception;
+
+    public StatementSyntaxError(Token token, ParseException exception) {
+        super(token, token);
+        this.exception = exception;
+    }
+
+    @Override
+    public ParseException exception() {
+        return exception;
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/StatementVar.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/StatementVar.java
@@ -0,0 +1,20 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.Token;
+
+public final class StatementVar extends Statement {
+    public final TypeExpr type;
+    public final Token name;
+    public final Expression initValue;
+
+    public StatementVar(TypeExpr type, Token name, Expression initValue) {
+        super(type.start, initValue == null ? name : initValue.end);
+        this.type = type;
+        this.name = name;
+        this.initValue = initValue;
+    }
+
+    public String name() {
+        return name.content();
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/StatementWhile.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/StatementWhile.java
@@ -0,0 +1,14 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.Token;
+
+public final class StatementWhile extends Statement {
+    public final Expression condition;
+    public final Statement body;
+
+    public StatementWhile(Token start, Expression condition, Statement body) {
+        super(start, body.end);
+        this.condition = condition;
+        this.body = body;
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/SyntaxError.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/SyntaxError.java
@@ -0,0 +1,7 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.ParseException;
+
+public interface SyntaxError extends Error {
+    ParseException exception();
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/TypeDeclaration.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/TypeDeclaration.java
@@ -0,0 +1,8 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.SeaType;
+
+public interface TypeDeclaration {
+    String name();
+    SeaType type();
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/TypeExpr.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/TypeExpr.java
@@ -0,0 +1,19 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.SeaType;
+import mtmc.lang.sea.Token;
+
+import java.util.Objects;
+
+public abstract sealed class TypeExpr extends Ast permits TypeExprArray, TypeExprChar, TypeExprInt, TypeExprRef, TypeExprVoid, TypePointer {
+    private final SeaType type;
+
+    public TypeExpr(Token start, Token end, SeaType type) {
+        super(start, end);
+        this.type = Objects.requireNonNull(type);
+    }
+
+    public SeaType type() {
+        return type;
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/TypeExprArray.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/TypeExprArray.java
@@ -0,0 +1,13 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.SeaType;
+import mtmc.lang.sea.Token;
+
+public final class TypeExprArray extends TypeExpr {
+    public final TypeExpr inner;
+
+    public TypeExprArray(TypeExpr inner, Token end) {
+        super(inner.start, end, new SeaType.Pointer(inner.type()));
+        this.inner = inner;
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/TypeExprChar.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/TypeExprChar.java
@@ -0,0 +1,13 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.SeaType;
+import mtmc.lang.sea.Token;
+
+public final class TypeExprChar extends TypeExpr {
+    public final Token token;
+
+    public TypeExprChar(Token token) {
+        super(token, token, SeaType.CHAR);
+        this.token = token;
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/TypeExprInt.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/TypeExprInt.java
@@ -0,0 +1,10 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.SeaType;
+import mtmc.lang.sea.Token;
+
+public final class TypeExprInt extends TypeExpr {
+    public TypeExprInt(Token token) {
+        super(token, token, SeaType.INT);
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/TypeExprRef.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/TypeExprRef.java
@@ -0,0 +1,12 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.Token;
+
+public final class TypeExprRef extends TypeExpr {
+    public final TypeDeclaration decl;
+
+    public TypeExprRef(Token name, TypeDeclaration decl) {
+        super(name, name, decl.type());
+        this.decl = decl;
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/TypeExprVoid.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/TypeExprVoid.java
@@ -0,0 +1,10 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.SeaType;
+import mtmc.lang.sea.Token;
+
+public final class TypeExprVoid extends TypeExpr {
+    public TypeExprVoid(Token token) {
+        super(token, token, SeaType.VOID);
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/TypePointer.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/TypePointer.java
@@ -0,0 +1,13 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.SeaType;
+import mtmc.lang.sea.Token;
+
+public final class TypePointer extends TypeExpr {
+    public final TypeExpr component;
+
+    public TypePointer(TypeExpr component, Token star) {
+        super(component.start, star, new SeaType.Pointer(component.type()));
+        this.component = component;
+    }
+}
--- a/src/jvmMain/kotlin/mtmc/lang/sea/ast/Unit.java
+++ b/src/jvmMain/kotlin/mtmc/lang/sea/ast/Unit.java
@@ -0,0 +1,22 @@
+package mtmc.lang.sea.ast;
+
+import mtmc.lang.sea.Symbol;
+import mtmc.lang.sea.Token;
+
+import java.util.LinkedHashMap;
+import java.util.List;
+
+public final class Unit extends Ast {
+    public final String source;
+    public final String filename;
+    public final List<Declaration> declarations;
+    public final LinkedHashMap<String, Symbol> symbols;
+
+    public Unit(String filename, String source, List<Declaration> declarations, LinkedHashMap<String, Symbol> globals) {
+        super(Token.SOF, Token.EOF);
+        this.source = source;
+        this.filename = filename;
+        this.declarations = declarations;
+        this.symbols = globals;
+    }
+}
--- a/Show More
+++ b/Show More