diff --git a/readme.md b/readme.md
index caac057..2dcd34c 100644
--- a/readme.md
+++ b/readme.md
@@ -1,5 +1,13 @@
 # Paper computer simulator experiment
 
+## TODO
+
+- [ ] Implement CCF and CHP
+- [ ] Implement carry flag on SUB
+- [ ] Write some more complex test programs
+- [ ] Consider adding a way to visualize screen memory
+- [ ] Do a proper binary version...
+
 ## ISA
 
 0 END
diff --git a/simulator-sketch.js b/simulator-sketch.js
index 08d406d..dd8ff70 100644
--- a/simulator-sketch.js
+++ b/simulator-sketch.js
@@ -103,7 +103,7 @@ function CPU(mem) {
       this.instructionPointer = this.memory[addr];
     },
 
-    // UNIMPLEMENTED
+    // TODO: UNIMPLEMENTED
     carry_toggle: () => { return; },
     carry_hop: () => { return; },
   };