diff --git a/src/sixtypical/compiler.py b/src/sixtypical/compiler.py
new file mode 100644
index 0000000..1000fd1
--- /dev/null
+++ b/src/sixtypical/compiler.py
@@ -0,0 +1,83 @@
+# encoding: UTF-8
+
+from sixtypical.ast import Program, Routine, Block, Instr
+from sixtypical.model import (
+    ConstantRef, LocationRef,
+    REG_A, REG_X, REG_Y, FLAG_Z, FLAG_N, FLAG_V, FLAG_C
+)
+from sixtypical.gen6502 import Generator
+
+
+def compile_program(program):
+    assert isinstance(program, Program)
+    generator = Generator(49152)
+    routines = {r.name: r for r in program.routines}
+    for routine in program.routines:
+        compile_routine(routine, generator, routines)
+
+
+def compile_routine(routine, generator, routines):
+    assert isinstance(routine, Routine)
+    label = generator.emitter.make_label(routine.name)
+    compile_block(routine.block, generator, routines)
+    return label
+
+
+def compile_block(block, generator, routines):
+    assert isinstance(block, Block)
+    label = generator.emitter.make_label()
+    for instr in block.instrs:
+        compile_instr(instr, generator, routines)
+    return label
+
+
+def compile_instr(instr, generator, routines):
+    assert isinstance(instr, Instr)
+    opcode = instr.opcode
+    dest = instr.dest
+    src = instr.src
+
+    if opcode == 'ld':
+        if dest == REG_A:
+            if isinstance(src, ConstantRef):
+                # LDA #...
+                pass
+            elif:
+                # LDA abs
+                pass
+        elif dest == REG_X:
+        elif dest == REG_Y:
+        else:
+            raise KeyError
+    elif opcode == 'st':
+        if src == REG_A:
+            # assert isinstance(dest, MemoryRef)
+            # generate STA
+        else:
+            raise KeyError
+    elif opcode == 'add':
+        raise NotImplementedError
+    elif opcode == 'sub':
+        raise NotImplementedError
+    elif opcode == 'inc':
+        raise NotImplementedError
+    elif opcode == 'dec':
+        raise NotImplementedError
+    elif opcode == 'cmp':
+        raise NotImplementedError
+    elif opcode == 'and':
+        raise NotImplementedError
+    elif opcode == 'or':
+        raise NotImplementedError
+    elif opcode == 'xor':
+        raise NotImplementedError
+    elif opcode == 'shl':
+        raise NotImplementedError
+    elif opcode == 'shr':
+        raise NotImplementedError
+    elif opcode == 'call':
+        raise NotImplementedError
+    elif opcode == 'if':
+        raise NotImplementedError
+    else:
+        raise NotImplementedError
diff --git a/src/sixtypical/model.py b/src/sixtypical/model.py
index 6d97dd7..b869601 100644
--- a/src/sixtypical/model.py
+++ b/src/sixtypical/model.py
@@ -7,6 +7,9 @@ class LocationRef(object):
     def __repr__(self):
         return 'LocationRef(%r)' % self.name
 
+    def __eq__(self, other):
+        return isinstance(other, LocationRef) and other.name == self.name
+
 
 class ConstantRef(object):
     def __init__(self, value):
@@ -15,6 +18,9 @@ class ConstantRef(object):
     def __repr__(self):
         return 'ConstantRef(%r)' % self.value
 
+    def __eq__(self, other):
+        return isinstance(other, ConstantRef) and other.value == self.value
+
 
 # TODO type=byte