diff --git a/doc/compilers.txt b/doc/compilers.txt
index 49df1955..03d1e44d 100644
--- a/doc/compilers.txt
+++ b/doc/compilers.txt
@@ -77,3 +77,10 @@ SWEET16 - Woz's tiny bytecode interpreter on the Apple ][ integer BASIC ROM.
 Still emcumbered by Apple's copyright for the foreseeable future.
 http://6502.org/source/interpreters/sweet16.htm
 
+Quetzalcoatl - http://www.kdef.com/geek/vic/quetz.html
+
+UC65 - https://code.google.com/archive/p/uc65/
+
+Cowgol - https://github.com/davidgiven/cowgol
+
+AcheronVM - https://github.com/AcheronVM/acheronvm
diff --git a/doc/notes.txt b/doc/notes.txt
index 19b71230..766294b6 100644
--- a/doc/notes.txt
+++ b/doc/notes.txt
@@ -30,6 +30,8 @@ TODO:
 - slowdown beam for all platforms?
 - kbd shortcuts
 - PC x86 support
+- show errors in list
+- can't see 1st line in editor sometimes
 
 
 WEB WORKER FORMAT
@@ -51,5 +53,42 @@ only build files that have changed
 
 build options
 
-build project files
 
+BUILD PROJECT
+
+local/foo.project/*.*
+build all files in project
+send update for dependencies at startup (single file version)
+should be able to change file w/o reloading (Not platform tho)
+
+pulldown selects file in project, or goes back to parent
+gotta preserve editor windows for each one - window list
+make source/disasm window visible when debugging
+gutter info/errors in all files
+
+
+
+UI REFACTOR
+
+editor
+debugger
+disasm view
+memory
+profile
+
+separate into files
+
+window methods:
+- set
+- mode
+- get
+- changes
+- cursorActivity (inspect)
+- gutters (setCompileOutput)
+- current line / gutter marker (setCurrentLine / clearCurrentLine)
+- source map
+- global symbols
+- pixel editor / find comment (openBitmapEditorAtCursor)
+- update debug window (200 ms)
+
+file store mirrors that on worker
diff --git a/index.html b/index.html
index 9e2de388..d6e30564 100644
--- a/index.html
+++ b/index.html
@@ -233,7 +233,7 @@ ga('send', 'pageview');
 <script src="src/emu.js"></script>
 <script src="src/audio.js"></script>
 <script src="src/util.js"></script>
-<script src="src/disasm.js"></script>
+<script src="src/cpu/disasm6502.js"></script>
 <script src="src/ui.js"></script>
 <!-- <script src="src/audio/votrax.js"></script> -->
 
diff --git a/src/disasm.js b/src/cpu/disasm6502.js
similarity index 100%
rename from src/disasm.js
rename to src/cpu/disasm6502.js
diff --git a/src/platform/vcs.js b/src/platform/vcs.js
index c7226c6e..8d425f98 100644
--- a/src/platform/vcs.js
+++ b/src/platform/vcs.js
@@ -134,6 +134,38 @@ var pc2maxclocks = {};
 var jsrresult = {};
 var MAX_CLOCKS = 76*2;
 
+// [taken, not taken]
+var BRANCH_CONSTRAINTS = [
+  [{N:0},{N:1}],
+  [{N:1},{N:0}],
+  [{V:0},{V:1}],
+  [{V:1},{V:0}],
+  [{C:0},{C:1}],
+  [{C:1},{C:0}],
+  [{Z:0},{Z:1}],
+  [{Z:1},{Z:0}]
+];
+
+function constraintEquals(a,b) {
+  if (a == null || b == null)
+    return null;
+  for (var n in a) {
+    if (b[n] !== 'undefined')
+      return a[n] == b[n];
+  }
+  for (var n in b) {
+    if (a[n] !== 'undefined')
+      return a[n] == b[n];
+  }
+  return null;
+}
+
+function getClockCountsAtPC(pc) {
+  var opcode = platform.readAddress(pc);
+  var meta = platform.getOpcodeMetadata(opcode, pc);
+  return meta; // minCycles, maxCycles
+}
+
 function _traceInstructions(pc, minclocks, maxclocks, subaddr, constraints) {
   //console.log("trace", hex(pc), minclocks, maxclocks);
   if (!minclocks) minclocks = 0;
diff --git a/src/profileview.js b/src/profileview.js
new file mode 100644
index 00000000..94388f89
--- /dev/null
+++ b/src/profileview.js
@@ -0,0 +1,113 @@
+/* profiler window: currently unused */
+
+var profilelist;
+
+var pcdata = {};
+var prof_reads, prof_writes;
+var dumplines;
+
+function scrollProfileView(_ed) {
+  _ed.on('scroll', function(ed, changeobj) {
+    if (profilelist) {
+      profilelist.container.scrollTop = ed.getScrollInfo().top;
+    }
+  });
+}
+
+function updateProfileWindow() {
+  if (profilelist && sourcefile) {
+    $("#profileview").find('[data-index]').each(function(i,e) {
+      var div = $(e);
+      var lineno = div.attr('data-index') | 0;
+      var newtext = getProfileLine(lineno+1);
+      if (newtext) {
+        var oldtext = div.text();
+        if (oldtext != newtext)
+          div.text(newtext);
+      }
+    });
+  }
+}
+
+function createProfileWindow() {
+  profilelist = new VirtualList({
+    w:$("#emulator").width(),
+    h:$("#emulator").height(),
+    itemHeight: getVisibleEditorLineHeight(),
+    totalRows: getVisibleSourceFile().lineCount(),
+    generatorFn: function(row) {
+      var div = document.createElement("div");
+      div.appendChild(document.createTextNode("."));
+      return div;
+    }
+  });
+  $("#profileview").empty().append(profilelist.container);
+  updateProfileWindow();
+}
+
+function resetProfiler() {
+  prof_reads = [];
+  prof_writes = [];
+  pcdata = [];
+  dumplines = null;
+}
+
+function profileWindowCallback(a,v) {
+  if (platform.getPC) {
+    var pc = platform.getPC();
+    var pcd = pcdata[pc];
+    if (!pcd) {
+      pcd = pcdata[pc] = {nv:1};
+    }
+    if (a != pc) {
+      if (v >= 0) {
+        pcd.lastwa = a;
+        pcd.lastwv = v;
+      } else {
+        pcd.lastra = a;
+        pcd.lastrv = platform.readAddress(a);
+      }
+    } else {
+      pcd.nv++;
+    }
+  }
+}
+
+function getProfileLine(line) {
+  var srcfile = getVisibleSourceFile();
+  var offset = srcfile.line2offset[line];
+  var offset2 = srcfile.line2offset[line+1];
+  if (!(offset2 > offset)) offset2 = offset+1;
+  var s = '';
+  var nv = 0;
+  while (offset < offset2) {
+    var pcd = pcdata[offset];
+    if (pcd) {
+      nv += pcd.nv;
+      if (pcd.lastra >= 0) {
+        s += " rd [" + hex(pcd.lastra,4) + "] == " + hex(pcd.lastrv,2);
+      }
+      if (pcd.lastwa >= 0) {
+        s += " wr " + hex(pcd.lastwv,2) + " -> [" + hex(pcd.lastwa,4) + "]";
+      }
+    }
+    offset++;
+  }
+  return nv ? (lpad(nv+"",8) + s) : '.';
+}
+
+function toggleProfileWindow() {
+  if ($("#memoryview").is(':visible')) toggleMemoryWindow();
+  if ($("#profileview").is(':visible')) {
+    profilelist = null;
+    platform.getProbe().deactivate();
+    $("#emulator").show();
+    $("#profileview").hide();
+  } else {
+    createProfileWindow();
+    platform.getProbe().activate(profileWindowCallback);
+    $("#emulator").hide();
+    $("#profileview").show();
+  }
+}
+
diff --git a/src/ui.js b/src/ui.js
index 7aa96428..fbf04060 100644
--- a/src/ui.js
+++ b/src/ui.js
@@ -80,7 +80,7 @@ var TOOL_TO_SOURCE_STYLE = {
 }
 
 var worker = new Worker("./src/worker/workermain.js");
-var main_editor;
+var editor;
 var current_output;
 var current_preset_index = -1;
 var current_preset_id;
@@ -92,7 +92,6 @@ var compparams;
 var trace_pending_at_pc;
 var store;
 var pendingWorkerMessages = 0;
-var editor;
 var disasmview = CodeMirror(document.getElementById('disassembly'), {
   mode: 'z80',
   theme: 'cobalt',
@@ -100,18 +99,13 @@ var disasmview = CodeMirror(document.getElementById('disassembly'), {
   readOnly: true,
   styleActiveLine: true
 });
-scrollProfileView(disasmview);
+//scrollProfileView(disasmview);
+
+var currentDebugLine;
+var lastDebugInfo;
+var lastDebugState;
 
 var memorylist;
-var profilelist;
-
-function scrollProfileView(_ed) {
-  _ed.on('scroll', function(ed, changeobj) {
-    if (profilelist) {
-      profilelist.container.scrollTop = ed.getScrollInfo().top;
-    }
-  });
-}
 
 function newEditor(mode) {
   var isAsm = mode=='6502' || mode =='z80' || mode=='verilog' || mode=='gas'; // TODO
@@ -141,11 +135,11 @@ function newEditor(mode) {
       inspectVariable(editor);
     }
   });
-  scrollProfileView(editor);
+  //scrollProfileView(editor);
   editor.setOption("mode", mode);
 }
 
-function inspectVariable(editor, name) {
+function inspectVariable(ed, name) {
   var val;
   if (platform.inspect) {
     platform.inspect(name);
@@ -176,7 +170,7 @@ function updatePreset(current_preset_id, text) {
 
 function loadCode(text, fileid) {
   var tool = platform.getToolForFilename(fileid);
-  main_editor = newEditor(tool && TOOL_TO_SOURCE_STYLE[tool]);
+  newEditor(tool && TOOL_TO_SOURCE_STYLE[tool]);
   editor.setValue(text); // calls setCode()
   editor.clearHistory();
   current_output = null;
@@ -444,25 +438,6 @@ function setCode(text) {
   });
 }
 
-function arrayCompare(a,b) {
-  if (a == null && b == null) return true;
-  if (a == null) return false;
-  if (b == null) return false;
-  if (a.length != b.length) return false;
-  for (var i=0; i<a.length; i++)
-    if (a[i] != b[i])
-      return false;
-  return true;
-}
-
-function invertMap(m) {
-  var r = {};
-  if (m) {
-    for (var k in m) r[m[k]] = k;
-  }
-  return r;
-}
-
 function setCompileOutput(data) {
   if (data.unchanged) return;
   // TODO: kills current selection
@@ -472,7 +447,7 @@ function setCompileOutput(data) {
   }
   symbolmap = data.symbolmap;
   addr2symbol = invertMap(symbolmap);
-  addr2symbol[0x10000] = '__END__';
+  addr2symbol[0x10000] = '__END__'; // TODO?
   compparams = data.params;
   updatePreset(current_preset_id, editor.getValue()); // update persisted entry
   // errors?
@@ -516,7 +491,7 @@ function setCompileOutput(data) {
         platform.loadROM(getCurrentPresetTitle(), rom);
         if (!userPaused) resume();
         current_output = rom;
-        resetProfiler();
+        //resetProfiler();
         toolbar.removeClass("has-errors");
       } catch (e) {
         console.log(e); // TODO: show error
@@ -576,10 +551,6 @@ worker.onmessage = function(e) {
   setCompileOutput(e.data);
 }
 
-var currentDebugLine;
-var lastDebugInfo;
-var lastDebugState;
-
 function setCurrentLine(line) {
   function addCurrentMarker(line) {
     var div = document.createElement("div");
@@ -741,53 +712,6 @@ function clearBreakpoint() {
   showMemory();
 }
 
-function getClockCountsAtPC(pc) {
-  var opcode = platform.readAddress(pc);
-  var meta = platform.getOpcodeMetadata(opcode, pc);
-  return meta; // minCycles, maxCycles
-}
-
-function byte2signed(b) {
-  b &= 0xff;
-  return (b < 0x80) ? b : -(256-b);
-}
-
-// [taken, not taken]
-var BRANCH_CONSTRAINTS = [
-  [{N:0},{N:1}],
-  [{N:1},{N:0}],
-  [{V:0},{V:1}],
-  [{V:1},{V:0}],
-  [{C:0},{C:1}],
-  [{C:1},{C:0}],
-  [{Z:0},{Z:1}],
-  [{Z:1},{Z:0}]
-];
-
-function constraintEquals(a,b) {
-  if (a == null || b == null)
-    return null;
-  for (var n in a) {
-    if (b[n] !== 'undefined')
-      return a[n] == b[n];
-  }
-  for (var n in b) {
-    if (a[n] !== 'undefined')
-      return a[n] == b[n];
-  }
-  return null;
-}
-
-/*
-function showLoopTimingForCurrentLine() {
-  var line = getCurrentLine();
-  var pc = line2offset[line];
-  if (pc) {
-    showLoopTimingForPC(pc);
-  }
-}
-*/
-
 function jumpToLine(ed, i) {
     var t = ed.charCoords({line: i, ch: 0}, "local").top;
     var middleHeight = ed.getScrollerElement().offsetHeight / 2;
@@ -872,7 +796,7 @@ function toggleDisassembly() {
   $("#disassembly").toggle();
   $("#editor").toggle();
   updateDisassembly();
-  if (profilelist) createProfileWindow();
+  //if (profilelist) createProfileWindow();
 }
 
 function resetAndDebug() {
@@ -890,12 +814,14 @@ function resetAndDebug() {
   }
 }
 
+var lastBreakExpr = "c.PC = 0x6000";
 function _breakExpression() {
-  var exprs = window.prompt("Enter break expression", "c.PC == 0x6000"); // TODO
+  var exprs = window.prompt("Enter break expression", lastBreakExpr);
   if (exprs) {
     var fn = new Function('c', 'return (' + exprs + ');');
     setupBreakpoint();
     platform.runEval(fn);
+    lastBreakExpr = exprs;
   }
 }
 
@@ -912,26 +838,11 @@ function getSymbolAtAddress(a) {
 function updateDebugWindows() {
   if (platform.isRunning()) {
     updateMemoryWindow();
-    updateProfileWindow();
+    //updateProfileWindow();
   }
   setTimeout(updateDebugWindows, 200);
 }
 
-function updateProfileWindow() {
-  if (profilelist && sourcefile) {
-    $("#profileview").find('[data-index]').each(function(i,e) {
-      var div = $(e);
-      var lineno = div.attr('data-index') | 0;
-      var newtext = getProfileLine(lineno+1);
-      if (newtext) {
-        var oldtext = div.text();
-        if (oldtext != newtext)
-          div.text(newtext);
-      }
-    });
-  }
-}
-
 function updateMemoryWindow() {
   if (memorylist) {
     $("#memoryview").find('[data-index]').each(function(i,e) {
@@ -1058,7 +969,7 @@ function showMemoryWindow() {
 }
 
 function toggleMemoryWindow() {
-  if ($("#profileview").is(':visible')) toggleProfileWindow();
+  //if ($("#profileview").is(':visible')) toggleProfileWindow();
   if ($("#memoryview").is(':visible')) {
     memorylist = null;
     $("#emulator").show();
@@ -1070,92 +981,6 @@ function toggleMemoryWindow() {
   }
 }
 
-function createProfileWindow() {
-  profilelist = new VirtualList({
-    w:$("#emulator").width(),
-    h:$("#emulator").height(),
-    itemHeight: getVisibleEditorLineHeight(),
-    totalRows: getVisibleSourceFile().lineCount(),
-    generatorFn: function(row) {
-      var div = document.createElement("div");
-      div.appendChild(document.createTextNode("."));
-      return div;
-    }
-  });
-  $("#profileview").empty().append(profilelist.container);
-  updateProfileWindow();
-}
-
-var pcdata = {};
-var prof_reads, prof_writes;
-var dumplines;
-
-function resetProfiler() {
-  prof_reads = [];
-  prof_writes = [];
-  pcdata = [];
-  dumplines = null;
-}
-
-function profileWindowCallback(a,v) {
-  if (platform.getPC) {
-    var pc = platform.getPC();
-    var pcd = pcdata[pc];
-    if (!pcd) {
-      pcd = pcdata[pc] = {nv:1};
-    }
-    if (a != pc) {
-      if (v >= 0) {
-        pcd.lastwa = a;
-        pcd.lastwv = v;
-      } else {
-        pcd.lastra = a;
-        pcd.lastrv = platform.readAddress(a);
-      }
-    } else {
-      pcd.nv++;
-    }
-  }
-}
-
-function getProfileLine(line) {
-  var srcfile = getVisibleSourceFile();
-  var offset = srcfile.line2offset[line];
-  var offset2 = srcfile.line2offset[line+1];
-  if (!(offset2 > offset)) offset2 = offset+1;
-  var s = '';
-  var nv = 0;
-  while (offset < offset2) {
-    var pcd = pcdata[offset];
-    if (pcd) {
-      nv += pcd.nv;
-      if (pcd.lastra >= 0) {
-        s += " rd [" + hex(pcd.lastra,4) + "] == " + hex(pcd.lastrv,2);
-      }
-      if (pcd.lastwa >= 0) {
-        s += " wr " + hex(pcd.lastwv,2) + " -> [" + hex(pcd.lastwa,4) + "]";
-      }
-    }
-    offset++;
-  }
-  return nv ? (lpad(nv+"",8) + s) : '.';
-}
-
-function toggleProfileWindow() {
-  if ($("#memoryview").is(':visible')) toggleMemoryWindow();
-  if ($("#profileview").is(':visible')) {
-    profilelist = null;
-    platform.getProbe().deactivate();
-    $("#emulator").show();
-    $("#profileview").hide();
-  } else {
-    createProfileWindow();
-    platform.getProbe().activate(profileWindowCallback);
-    $("#emulator").hide();
-    $("#profileview").show();
-  }
-}
-
 function handleWindowMessage(e) {
   //console.log("window message", e.data);
   if (e.data.bytes) {
@@ -1327,9 +1152,9 @@ function setupDebugControls(){
   } else if (platform.readAddress) {
     $("#dbg_memory").click(toggleMemoryWindow).show();
   }
-  if (platform.getProbe) {
+  /*if (platform.getProbe) {
     $("#dbg_profile").click(toggleProfileWindow).show();
-  }
+  }*/
   if (platform.saveState) { // TODO: only show if listing or disasm available
     $("#dbg_disasm").click(toggleDisassembly).show();
   }
diff --git a/src/util.js b/src/util.js
index ea3cc6d8..170a2e0e 100644
--- a/src/util.js
+++ b/src/util.js
@@ -1,6 +1,12 @@
+"use strict";
 
 function lpad(s,n) { while(s.length<n) s=" "+s; return s; }
 
+function byte2signed(b) {
+  b &= 0xff;
+  return (b < 0x80) ? b : -(256-b);
+}
+
 function hex(v, nd) {
   try {
     if (!nd) nd = 2;
@@ -13,6 +19,25 @@ function hex(v, nd) {
   }
 }
 
+function arrayCompare(a,b) {
+  if (a == null && b == null) return true;
+  if (a == null) return false;
+  if (b == null) return false;
+  if (a.length != b.length) return false;
+  for (var i=0; i<a.length; i++)
+    if (a[i] != b[i])
+      return false;
+  return true;
+}
+
+function invertMap(m) {
+  var r = {};
+  if (m) {
+    for (var k in m) r[m[k]] = k;
+  }
+  return r;
+}
+
 function highlightDifferences(s1, s2) {
   var split1 = s1.split(/(\S+\s+)/).filter(function(n) {return n});
   var split2 = s2.split(/(\S+\s+)/).filter(function(n) {return n});
diff --git a/test/cli/6502/test6502disasm.js b/test/cli/6502/test6502disasm.js
index eb8b8542..7beead08 100644
--- a/test/cli/6502/test6502disasm.js
+++ b/test/cli/6502/test6502disasm.js
@@ -7,7 +7,7 @@ var includeInThisContext = function(path) {
     vm.runInThisContext(code, path);
 };
 
-includeInThisContext("src/disasm.js");
+includeInThisContext("src/cpu/disasm6502.js");
 
 describe('6502 disassembler', function() {
   it('Should work', function() {
diff --git a/testemu.html b/testemu.html
index c002a63c..19c7bff3 100644
--- a/testemu.html
+++ b/testemu.html
@@ -33,7 +33,7 @@
     <script src="src/cpu/z80fast.js"></script>
     <script src="src/emu.js"></script>
     <script src="src/util.js"></script>
-    <script src="src/disasm.js"></script>
+    <script src="src/cpu/disasm6502.js"></script>
     <script src="src/platform/vcs.js"></script>
     <script src="src/platform/mw8080bw.js"></script>
     <script src="src/platform/vicdual.js"></script>
diff --git a/viz.html b/viz.html
index 4e85c30e..011dd466 100644
--- a/viz.html
+++ b/viz.html
@@ -39,7 +39,7 @@ div.CodeMirror {
         <p class="lead">
           Edit a C source file, and see the Z80 assembly output update in real-time.
         </p>
-        <h6>Powered by <a target="_new" href="https://twitter.com/8bitworkshop">@8bitworkshop</a> and the
+        <h6>Powered by <a target="_new" href="http://8bitworkshop.com/">@8bitworkshop</a> and the
         <a href="http://sdcc.sourceforge.net/">Small Device C Compiler</a>.</h6>
         <select id="preset_select" name="">
         </select>
@@ -62,7 +62,10 @@ Javatari = {};
 PLATFORMS = {};
 </script>
 
-<script src="src/cpu/z80.js"></script>
+<script src="localForage/dist/localforage.nopromises.js"></script>
+
+<script src="src/store.js"></script>
+<script src="src/cpu/z80fast.js"></script>
 <script src="src/util.js"></script>
 <script src="src/emu.js"></script>
 <script src="src/ui.js"></script>