diff --git a/il65/src/il65/Main.kt b/il65/src/il65/Main.kt
index cc68601cc..075bc8b96 100644
--- a/il65/src/il65/Main.kt
+++ b/il65/src/il65/Main.kt
@@ -3,8 +3,10 @@ package il65
 import java.nio.file.Paths
 import il65.ast.*
 import il65.parser.*
+import il65.compiler.*
 import il65.optimizing.optimizeExpressions
 import il65.optimizing.optimizeStatements
+import kotlin.system.exitProcess
 
 
 fun main(args: Array<String>) {
@@ -20,20 +22,34 @@ fun main(args: Array<String>) {
 
         moduleAst.optimizeExpressions(globalNamespace)
         moduleAst.optimizeStatements(globalNamespace)
-        moduleAst.checkValid(globalNamespace)      // check if final tree is valid
+        val globalNamespaceAfterOptimize = moduleAst.namespace()  // it could have changed in the meantime
+        moduleAst.checkValid(globalNamespaceAfterOptimize)        // check if final tree is valid
 
         // determine special compiler options
         val options = moduleAst.statements.filter { it is Directive && it.directive=="%option" }.flatMap { (it as Directive).args }.toSet()
         val optionEnableFloats = options.contains(DirectiveArg(null, "enable_floats", null))
 
-        if(optionEnableFloats) println("Compiler: floats enabled")
+        val compilerOptions = CompilationOptions(OutputType.PRG,
+                Launcher.BASIC,
+                Zeropage.COMPATIBLE,
+                optionEnableFloats)
+
+        val intermediate = moduleAst.compileToIntermediate(compilerOptions, globalNamespaceAfterOptimize)
+        intermediate.optimize()
+
+//        val assembler = intermediate.compileToAssembly()
+//        assembler.assemble(compilerOptions, "input", "output")
+//        val monitorfile = assembler.genereateBreakpointList()
+
+        // start the vice emulator
+//        val program = "foo"
+//        val cmdline = listOf("x64", "-moncommands", monitorfile,
+//                "-autostartprgmode", "1", "-autostart-warp", "-autostart", program)
+//        ProcessBuilder(cmdline).inheritIO().start()
 
-        // todo compile to asm...
-        moduleAst.statements.forEach {
-            println(it)
-        }
     } catch (px: ParsingFailedError) {
         System.err.println(px.message)
+        exitProcess(1)
     }
 }
 
diff --git a/il65/src/il65/compiler/Compiler.kt b/il65/src/il65/compiler/Compiler.kt
new file mode 100644
index 000000000..5604fc7e2
--- /dev/null
+++ b/il65/src/il65/compiler/Compiler.kt
@@ -0,0 +1,105 @@
+package il65.compiler
+
+import il65.ast.INameScope
+import il65.ast.Module
+import kotlin.system.exitProcess
+
+
+fun Module.compileToIntermediate(options: CompilationOptions, namespace: INameScope): IntermediateForm {
+
+    val compiler = Compiler(options, namespace)
+    return compiler.compile(this)
+}
+
+
+class Compiler(val options: CompilationOptions, val namespace: INameScope) {
+    fun compile(module: Module) : IntermediateForm {
+        println("......@TODO compile Ast into Intermediate result......")       // todo
+        return IntermediateForm(module.name)
+    }
+}
+
+
+class IntermediateForm(val name: String) {
+    fun optimize() {
+        println("......@TODO optimize intermediate result......")       // todo
+    }
+
+    fun compileToAssembly(): AssemblyResult {
+        println("......@TODO compile intermediate result to assembly code......")       // todo
+        return AssemblyResult(name)
+    }
+
+}
+
+enum class OutputType {
+    RAW,
+    PRG
+}
+
+enum class Launcher {
+    BASIC,
+    NONE
+}
+
+enum class Zeropage {
+    COMPATIBLE,
+    FULL,
+    FULL_RESTORE
+}
+
+
+data class CompilationOptions(val output: OutputType,
+                              val launcher: Launcher,
+                              val zeropage: Zeropage,
+                              val floats: Boolean)
+
+
+class AssemblyResult(val name: String) {
+    fun assemble(options: CompilationOptions, inputfilename: String, outputfilename: String) {
+        println("......@TODO assemble with 64tass......")       // todo
+
+        val command = mutableListOf("64tass", "--ascii", "--case-sensitive", "-Wall", "-Wno-strict-bool",
+            "--dump-labels", "--vice-labels", "-l", outputfilename+".vice-mon-list",
+            "--no-monitor", "--output", outputfilename, inputfilename)
+
+        when(options.output) {
+            OutputType.PRG -> {
+                command.add("--cbm-prg")
+                println("\nCreating C-64 prg.")
+            }
+            OutputType.RAW -> {
+                command.add("--nostart")
+                println("\nCreating raw binary.")
+            }
+        }
+
+        val proc = ProcessBuilder(command).inheritIO().start()
+        val result = proc.waitFor()
+        if(result!=0) {
+            System.err.println("assembler failed with returncode $result")
+            exitProcess(result)
+        }
+    }
+
+    fun genereateBreakpointList(): String {
+/*
+    def generate_breakpoint_list(self, program_filename: str) -> str:
+        breakpoints = []
+        vice_mon_file = program_filename + ".vice-mon-list"
+        with open(vice_mon_file, "rU") as f:
+            for line in f:
+                match = re.fullmatch(r"al (?P<address>\w+) \S+_il65_breakpoint_\d+.?", line, re.DOTALL)
+                if match:
+                    breakpoints.append("$" + match.group("address"))
+        with open(vice_mon_file, "at") as f:
+            print("; vice monitor breakpoint list now follows", file=f)
+            print("; {:d} breakpoints have been defined here".format(len(breakpoints)), file=f)
+            print("del", file=f)
+            for b in breakpoints:
+                print("break", b, file=f)
+        return vice_mon_file
+ */
+        return "monitorfile.txt"
+    }
+}
\ No newline at end of file