diff --git a/electron-preload.js b/electron-preload.js
index 103c1500..ae606b8f 100644
--- a/electron-preload.js
+++ b/electron-preload.js
@@ -1,18 +1,38 @@
 // preload.js for Electron app
 const { ipcRenderer } = require('electron');
+const fs = require('fs');
+const modpath = require('path');
+
+// workspace root path
+// TODO: reloading clears this
+var wsroot = null;
+
+// from browser: read workspace file synchronously
+window.getWorkspaceFile = function(path, filetype) {
+  if (wsroot == null) throw Error("no workspace root set");
+  try {
+    // TODO: detect text or binary, or decide based on incbin vs. source file
+    var fullpath = modpath.join(wsroot, modpath.normalize(path));
+    var data = fs.readFileSync(fullpath, {encoding:filetype=='text'?'utf8':'binary'});
+    console.log("getWorkspaceFile", path, filetype);
+    // TODO: add to watched files
+    return data;
+  } catch (e) {
+    console.log(e);
+    return null;
+  }
+}
 
 process.once('loaded', () => {
-  ipcRenderer.on('updateFile', (event, data) => {
-    console.log('updateFile', data);
-    data.cmd = 'updateFile';
-    postMessage(data);
+  // from electron.js: set workspace root directory
+  ipcRenderer.on('setWorkspaceRoot', (event, data) => {
+    wsroot = data.root;
+    console.log('setWorkspaceRoot', wsroot);
   });
-  window.addEventListener('message', event => {
-    const message = event.data;
-    console.log('MESSAGE', event, message);
-    //if (message.myTypeField === 'my-custom-message') {
-      //ipcRenderer.send('custom-message', message);
-    //}
+  // from electron.js: file changed
+  ipcRenderer.on('fileChanged', (event, data) => {
+    var path = data.path;
+    console.log('fileChanged', path);
+    window.reloadWorkspaceFile(path);
   });
-  //ipcRenderer.send('hello', true);
 });
diff --git a/electron.js b/electron.js
index a02a394d..6beead1f 100644
--- a/electron.js
+++ b/electron.js
@@ -1,50 +1,73 @@
-const { app, ipcMain, ipcRenderer, Menu, BrowserWindow } = require('electron')
+const { app, dialog, ipcMain, ipcRenderer, Menu, BrowserWindow } = require('electron')
 const modpath = require('path')
 const fs = require('fs')
 const {URLSearchParams} = require('url')
 const isMac = process.platform === 'darwin'
 const chokidar = require('chokidar')
+const Store = require('electron-store');
+const store = new Store();
+const KEY_lastWorkspaceFilePath = "lastWorkspaceFilePath";
 
 // file watcher
+// TODO: add workspace metadata for platform, ROM output, README, etc.
 class Workspace {
   constructor(directory, mainfile, wnd) {
     this.directory = directory;
     this.mainfile = mainfile;
+    wnd.webContents.send('setWorkspaceRoot', {root:this.directory});
     this.watcher = chokidar.watch(modpath.join(directory, mainfile));
     this.watcher.on('all', (event, path) => {
       console.log(event, path);
       switch (event) {
         case 'add':
-          /*
-          wnd.webContents.send('updateFile', {
-            main: modpath.relative(mainDirectoryPath, mainFilePath),
-            path: modpath.relative(mainDirectoryPath, path),
-            data: data,
+        case 'change':
+          wnd.webContents.send('fileChanged', {
+            path: modpath.relative(this.directory, path),
           });
-          */
           break;
       }
     });
+    console.log("workspace opened", this.directory, this.mainfile);
+  }
+  close() {
+    if (this.watcher) {
+      this.watcher.close();
+      this.watcher = null;
+      console.log("workspace closed", this.directory, this.mainfile);
+    }
   }
 }
 
 function openFile(path) {
-  var data = new Uint8Array(fs.readFileSync(path));
+  if (!fs.existsSync(path)) {
+    dialog.showMessageBox({
+      type: "error",
+      message: "File not found.",
+      detail: path
+    });
+    return;
+  }
   var dirname = modpath.dirname(path);
   var filename = modpath.basename(path);
-  //var platform_id = 'vcs'; // TODO: which platform?
-  //var wnd = createWindow({repo_id:dirname, file:filename, platform_id:platform_id});
   var wnd = BrowserWindow.getFocusedWindow();
+  if (wnd.workspace) { wnd.workspace.close(); }
   var ws = new Workspace(dirname, filename, wnd);
   wnd.workspace = ws;
+  wnd.on('closed', () => {
+    ws.close();
+  });
   var qs = new URLSearchParams();
-  qs.set('ws', dirname);
+  qs.set('electron_ws', 1);
+  qs.set('repo', dirname);
   qs.set('file', filename);
-  wnd.loadURL(`file://${__dirname}/electron.html?${qs}`);
+  wnd.loadURL(`file://${__dirname}/electron.html?${qs}`).then(() => {
+    wnd.webContents.send('setWorkspaceRoot', {root:dirname});
+    app.addRecentDocument(path);
+    store.set(KEY_lastWorkspaceFilePath, path);
+  });
 }
 
 function openFileDialog() {
-  const { dialog } = require('electron')
   dialog.showOpenDialog({
     title: "Open File",
     properties: ['openFile','promptToCreate'],
@@ -56,6 +79,17 @@ function openFileDialog() {
   });
 }
 
+function openDefaultFile() {
+  createWindow();
+  /*
+  var lastfile = store.get(KEY_lastWorkspaceFilePath);
+  if (lastfile != null) {
+    openFile(lastfile);
+  }
+  */
+}
+
+/*
 function openWorkspace() {
   const { dialog } = require('electron')
   console.log(dialog.showOpenDialog({
@@ -64,6 +98,7 @@ function openWorkspace() {
     message: "Choose a directory that holds your source files.",
   }))
 }
+*/
 
 function openURL(url) {
   return async () => {
@@ -94,13 +129,22 @@ function buildMenu() {
     {
       label: 'File',
       submenu: [
-        /*
         {
           label: 'Open File...',
           click: openFileDialog,
           accelerator: 'CmdOrCtrl+O',
         },
-        */
+        // When a file is requested from the recent documents menu, the open-file event of app module will be emitted for it.
+        {
+          "label":"Open Recent",
+          "role":"recentdocuments",
+          "submenu":[
+            {
+              "label":"Clear Recent",
+              "role":"clearrecentdocuments"
+            }
+          ]
+        },
         { type: 'separator' },
         isMac ? { role: 'close' } : { role: 'quit' }
       ]
@@ -202,13 +246,15 @@ function createWindow () {
       preload: modpath.join(__dirname, './electron-preload.js'),
       nodeIntegration: false,
       enableRemoteModule: false,
-      contextIsolation: true,
-      sandbox: true,
+      contextIsolation: false,
+      sandbox: false,
     }
   })
 
   // and load the index.html of the app.
-  win.loadFile('electron.html')
+  win.loadFile('electron.html', {
+    search: 'repo=/'
+  })
 
   // Open the DevTools.
   //win.webContents.openDevTools()
@@ -221,7 +267,7 @@ function createWindow () {
 // This method will be called when Electron has finished
 // initialization and is ready to create browser windows.
 // Some APIs can only be used after this event occurs.
-app.whenReady().then(buildMenu).then(createWindow)
+app.whenReady().then(buildMenu).then(openDefaultFile)
 
 // Quit when all windows are closed, except on macOS. There, it's common
 // for applications and their menu bar to stay active until the user quits
@@ -240,6 +286,10 @@ app.on('activate', () => {
   }
 })
 
+app.on('open-file', (event, path) => {
+  openFile(path);
+})
+
 // In this file you can include the rest of your app's specific main process
 // code. You can also put them in separate files and require them here.
 
diff --git a/package-lock.json b/package-lock.json
index 80f1543d..d7077f05 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -251,6 +251,11 @@
       "integrity": "sha1-bZUX654DDSQ2ZmZR6GvZ9vE1M8k=",
       "dev": true
     },
+    "atomically": {
+      "version": "1.3.2",
+      "resolved": "https://registry.npmjs.org/atomically/-/atomically-1.3.2.tgz",
+      "integrity": "sha512-MAiqx5ir1nOoMeG2vLXJnj4oFROJYB1hMqa2aAo6GQVIkPdkIcrq9W9SR0OaRtvEowO7Y2bsXqKFuDMTO4iOAQ=="
+    },
     "author-regex": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/author-regex/-/author-regex-1.0.0.tgz",
@@ -590,6 +595,46 @@
         "typedarray": "^0.0.6"
       }
     },
+    "conf": {
+      "version": "7.1.1",
+      "resolved": "https://registry.npmjs.org/conf/-/conf-7.1.1.tgz",
+      "integrity": "sha512-njOu3so+7zcR1oQzXKP0mpPMKRf+riaaWmxBUhgP/c9k32PuDX/SQ+N6cO6ZylY6NOZGPwgzicGxdlRGXUOkSQ==",
+      "requires": {
+        "ajv": "^6.12.2",
+        "atomically": "^1.3.1",
+        "debounce-fn": "^4.0.0",
+        "dot-prop": "^5.2.0",
+        "env-paths": "^2.2.0",
+        "json-schema-typed": "^7.0.3",
+        "make-dir": "^3.1.0",
+        "onetime": "^5.1.0",
+        "pkg-up": "^3.1.0",
+        "semver": "^7.3.2"
+      },
+      "dependencies": {
+        "ajv": {
+          "version": "6.12.3",
+          "resolved": "https://registry.npmjs.org/ajv/-/ajv-6.12.3.tgz",
+          "integrity": "sha512-4K0cK3L1hsqk9xIb2z9vs/XU+PGJZ9PNpJRDS9YLzmNdX6jmVPfamLvTJr0aDAusnHyCHO6MjzlkAsgtqp9teA==",
+          "requires": {
+            "fast-deep-equal": "^3.1.1",
+            "fast-json-stable-stringify": "^2.0.0",
+            "json-schema-traverse": "^0.4.1",
+            "uri-js": "^4.2.2"
+          }
+        },
+        "fast-deep-equal": {
+          "version": "3.1.3",
+          "resolved": "https://registry.npmjs.org/fast-deep-equal/-/fast-deep-equal-3.1.3.tgz",
+          "integrity": "sha512-f3qQ9oQy9j2AhBe/H9VC91wLmKBCCU/gDOnKNAYG5hswO7BLKj09Hc5HYNz9cGI++xlpDCIgDaitVs03ATR84Q=="
+        },
+        "semver": {
+          "version": "7.3.2",
+          "resolved": "https://registry.npmjs.org/semver/-/semver-7.3.2.tgz",
+          "integrity": "sha512-OrOb32TeeambH6UrhtShmF7CRDqhL6/5XpPNp2DuRH6+9QLw/orhp72j87v8Qa1ScDkvrrBNpZcDejAirJmfXQ=="
+        }
+      }
+    },
     "config-chain": {
       "version": "1.1.12",
       "resolved": "https://registry.npmjs.org/config-chain/-/config-chain-1.1.12.tgz",
@@ -642,6 +687,14 @@
         "whatwg-url": "^7.0.0"
       }
     },
+    "debounce-fn": {
+      "version": "4.0.0",
+      "resolved": "https://registry.npmjs.org/debounce-fn/-/debounce-fn-4.0.0.tgz",
+      "integrity": "sha512-8pYCQiL9Xdcg0UPSD3d+0KMlOjp+KGU5EPwYddgzQ7DATsg4fuUDjQtsYLmWjnk2obnNHgV3vE2Y4jejSOJVBQ==",
+      "requires": {
+        "mimic-fn": "^3.0.0"
+      }
+    },
     "debug": {
       "version": "4.1.1",
       "resolved": "https://registry.npmjs.org/debug/-/debug-4.1.1.tgz",
@@ -721,6 +774,14 @@
         "webidl-conversions": "^4.0.2"
       }
     },
+    "dot-prop": {
+      "version": "5.2.0",
+      "resolved": "https://registry.npmjs.org/dot-prop/-/dot-prop-5.2.0.tgz",
+      "integrity": "sha512-uEUyaDKoSQ1M4Oq8l45hSE26SnTxL6snNnqvK/VWx5wJhmff5z0FUVJDKDanor/6w3kzE3i7XZOk+7wC0EXr1A==",
+      "requires": {
+        "is-obj": "^2.0.0"
+      }
+    },
     "duplexer3": {
       "version": "0.1.4",
       "resolved": "https://registry.npmjs.org/duplexer3/-/duplexer3-0.1.4.tgz",
@@ -945,6 +1006,22 @@
         }
       }
     },
+    "electron-store": {
+      "version": "6.0.0",
+      "resolved": "https://registry.npmjs.org/electron-store/-/electron-store-6.0.0.tgz",
+      "integrity": "sha512-ujb0a/6gxMxb9vOQ2BjOehK9VCyq5OKvttekd9v/tohA9oBHnAdV+Vxu4eoRh+/F9ShPFhcvDZkMdqO5i+TXUw==",
+      "requires": {
+        "conf": "^7.1.1",
+        "type-fest": "^0.16.0"
+      },
+      "dependencies": {
+        "type-fest": {
+          "version": "0.16.0",
+          "resolved": "https://registry.npmjs.org/type-fest/-/type-fest-0.16.0.tgz",
+          "integrity": "sha512-eaBzG6MxNzEn9kiwvtre90cXaNLkmadMWa1zQMs3XORCXNbsH/OewwbxC5ia9dCxIxnTAsSxXJaa/p5y8DlvJg=="
+        }
+      }
+    },
     "emoji-regex": {
       "version": "7.0.3",
       "resolved": "https://registry.npmjs.org/emoji-regex/-/emoji-regex-7.0.3.tgz",
@@ -979,8 +1056,7 @@
     "env-paths": {
       "version": "2.2.0",
       "resolved": "https://registry.npmjs.org/env-paths/-/env-paths-2.2.0.tgz",
-      "integrity": "sha512-6u0VYSCo/OW6IoD5WCLLy9JUGARbamfSavcNXry/eu8aHVFei6CD3Sw+VGX5alea1i9pgPHW0mbu6Xj0uBh7gA==",
-      "dev": true
+      "integrity": "sha512-6u0VYSCo/OW6IoD5WCLLy9JUGARbamfSavcNXry/eu8aHVFei6CD3Sw+VGX5alea1i9pgPHW0mbu6Xj0uBh7gA=="
     },
     "error-ex": {
       "version": "1.3.2",
@@ -1115,8 +1191,7 @@
     "fast-json-stable-stringify": {
       "version": "2.0.0",
       "resolved": "https://registry.npmjs.org/fast-json-stable-stringify/-/fast-json-stable-stringify-2.0.0.tgz",
-      "integrity": "sha1-1RQsDK7msRifh9OnYREGT4bIu/I=",
-      "dev": true
+      "integrity": "sha1-1RQsDK7msRifh9OnYREGT4bIu/I="
     },
     "fast-levenshtein": {
       "version": "2.0.6",
@@ -1199,7 +1274,6 @@
       "version": "3.0.0",
       "resolved": "https://registry.npmjs.org/find-up/-/find-up-3.0.0.tgz",
       "integrity": "sha512-1yD6RmLI1XBfxugvORwlck6f75tYL+iR0jqwsOrOxMZyGYqUuDhJ0l4AXdO1iX/FTs9cBAMEk1gWSEx1kSbylg==",
-      "dev": true,
       "requires": {
         "locate-path": "^3.0.0"
       }
@@ -1675,6 +1749,11 @@
       "resolved": "https://registry.npmjs.org/is-number/-/is-number-7.0.0.tgz",
       "integrity": "sha512-41Cifkg6e8TylSpdtTpeLVMqvSBEVzTttHvERD741+pnZ8ANv0004MRL43QKPDlK9cGvNp6NZWZUBlbGXYxxng=="
     },
+    "is-obj": {
+      "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/is-obj/-/is-obj-2.0.0.tgz",
+      "integrity": "sha512-drqDG3cbczxxEJRoOXcOjtdp1J/lyp1mNn0xaznRs8+muBhgQcrnbspox5X5fOw0HnMnbfDzvnEMEtqDEJEo8w=="
+    },
     "is-regex": {
       "version": "1.1.0",
       "resolved": "https://registry.npmjs.org/is-regex/-/is-regex-1.1.0.tgz",
@@ -1809,8 +1888,12 @@
     "json-schema-traverse": {
       "version": "0.4.1",
       "resolved": "https://registry.npmjs.org/json-schema-traverse/-/json-schema-traverse-0.4.1.tgz",
-      "integrity": "sha1-afaofZUTq4u4/mO9sJecRI5oRmA=",
-      "dev": true
+      "integrity": "sha1-afaofZUTq4u4/mO9sJecRI5oRmA="
+    },
+    "json-schema-typed": {
+      "version": "7.0.3",
+      "resolved": "https://registry.npmjs.org/json-schema-typed/-/json-schema-typed-7.0.3.tgz",
+      "integrity": "sha512-7DE8mpG+/fVw+dTpjbxnx47TaMnDfOI1jwft9g1VybltZCduyRQPJPvc+zzKY9WPHxhPWczyFuYa6I8Mw4iU5A=="
     },
     "json-stringify-safe": {
       "version": "5.0.1",
@@ -1929,7 +2012,6 @@
       "version": "3.0.0",
       "resolved": "https://registry.npmjs.org/locate-path/-/locate-path-3.0.0.tgz",
       "integrity": "sha512-7AO748wWnIhNqAuaty2ZWHkQHRSNfPVIsPIfwEOWO22AmaoVrWavlOcMR5nzTLNYvp36X220/maaRsrec1G65A==",
-      "dev": true,
       "requires": {
         "p-locate": "^3.0.0",
         "path-exists": "^3.0.0"
@@ -2021,6 +2103,21 @@
         "pkginfo": "~0.4.0"
       }
     },
+    "make-dir": {
+      "version": "3.1.0",
+      "resolved": "https://registry.npmjs.org/make-dir/-/make-dir-3.1.0.tgz",
+      "integrity": "sha512-g3FeP20LNwhALb/6Cz6Dd4F2ngze0jz7tbzrD2wAV+o9FeNHe4rL+yK2md0J/fiSf1sa1ADhXqi5+oVwOM/eGw==",
+      "requires": {
+        "semver": "^6.0.0"
+      },
+      "dependencies": {
+        "semver": {
+          "version": "6.3.0",
+          "resolved": "https://registry.npmjs.org/semver/-/semver-6.3.0.tgz",
+          "integrity": "sha512-b39TBaTSfV6yBrapU89p5fKekE2m/NwnDocOVruQFS1/veMgdzuPcnOM34M6CwxW8jH/lxEa5rBoDeUwu5HHTw=="
+        }
+      }
+    },
     "matcher": {
       "version": "3.0.0",
       "resolved": "https://registry.npmjs.org/matcher/-/matcher-3.0.0.tgz",
@@ -2055,6 +2152,11 @@
         "mime-db": "~1.38.0"
       }
     },
+    "mimic-fn": {
+      "version": "3.1.0",
+      "resolved": "https://registry.npmjs.org/mimic-fn/-/mimic-fn-3.1.0.tgz",
+      "integrity": "sha512-Ysbi9uYW9hFyfrThdDEQuykN4Ey6BuwPD2kpI5ES/nFTDn/98yxYNLZJcgUAKPT/mcrLLKaGzJR9YVxJrIdASQ=="
+    },
     "mimic-response": {
       "version": "1.0.1",
       "resolved": "https://registry.npmjs.org/mimic-response/-/mimic-response-1.0.1.tgz",
@@ -2318,6 +2420,21 @@
         "wrappy": "1"
       }
     },
+    "onetime": {
+      "version": "5.1.0",
+      "resolved": "https://registry.npmjs.org/onetime/-/onetime-5.1.0.tgz",
+      "integrity": "sha512-5NcSkPHhwTVFIQN+TUqXoS5+dlElHXdpAWu9I0HP20YOtIi+aZ0Ct82jdlILDxjLEAWwvm+qj1m6aEtsDVmm6Q==",
+      "requires": {
+        "mimic-fn": "^2.1.0"
+      },
+      "dependencies": {
+        "mimic-fn": {
+          "version": "2.1.0",
+          "resolved": "https://registry.npmjs.org/mimic-fn/-/mimic-fn-2.1.0.tgz",
+          "integrity": "sha512-OqbOk5oEQeAZ8WXWydlu9HJjz9WVdEIvamMCcXmuqUYjTknH/sqsWvhQ3vgwKFRR1HpjvNBKQ37nbJgYzGqGcg=="
+        }
+      }
+    },
     "optionator": {
       "version": "0.8.2",
       "resolved": "https://registry.npmjs.org/optionator/-/optionator-0.8.2.tgz",
@@ -2342,7 +2459,6 @@
       "version": "2.3.0",
       "resolved": "https://registry.npmjs.org/p-limit/-/p-limit-2.3.0.tgz",
       "integrity": "sha512-//88mFWSJx8lxCzwdAABTJL2MyWB12+eIY7MDL2SqLmAkeKU9qxRvWuSyTjm3FUmpBEMuFfckAIqEaVGUDxb6w==",
-      "dev": true,
       "requires": {
         "p-try": "^2.0.0"
       }
@@ -2351,7 +2467,6 @@
       "version": "3.0.0",
       "resolved": "https://registry.npmjs.org/p-locate/-/p-locate-3.0.0.tgz",
       "integrity": "sha512-x+12w/To+4GFfgJhBEpiDcLozRJGegY+Ei7/z0tSLkMmxGZNybVMSfWj9aJn8Z5Fc7dBUNJOOVgPv2H7IwulSQ==",
-      "dev": true,
       "requires": {
         "p-limit": "^2.0.0"
       }
@@ -2359,8 +2474,7 @@
     "p-try": {
       "version": "2.2.0",
       "resolved": "https://registry.npmjs.org/p-try/-/p-try-2.2.0.tgz",
-      "integrity": "sha512-R4nPAVTAU0B9D35/Gk3uJf/7XYbQcyohSKdvAxIRSNghFl4e71hVoGnBNQz9cWaXxO2I10KTC+3jMdvvoKw6dQ==",
-      "dev": true
+      "integrity": "sha512-R4nPAVTAU0B9D35/Gk3uJf/7XYbQcyohSKdvAxIRSNghFl4e71hVoGnBNQz9cWaXxO2I10KTC+3jMdvvoKw6dQ=="
     },
     "pako": {
       "version": "1.0.11",
@@ -2395,8 +2509,7 @@
     "path-exists": {
       "version": "3.0.0",
       "resolved": "https://registry.npmjs.org/path-exists/-/path-exists-3.0.0.tgz",
-      "integrity": "sha1-zg6+ql94yxiSXqfYENe1mwEP1RU=",
-      "dev": true
+      "integrity": "sha1-zg6+ql94yxiSXqfYENe1mwEP1RU="
     },
     "path-is-absolute": {
       "version": "1.0.1",
@@ -2451,6 +2564,14 @@
       "dev": true,
       "optional": true
     },
+    "pkg-up": {
+      "version": "3.1.0",
+      "resolved": "https://registry.npmjs.org/pkg-up/-/pkg-up-3.1.0.tgz",
+      "integrity": "sha512-nDywThFk1i4BQK4twPQ6TA4RT8bDY96yeuCVBWL3ePARCiEKDRSrNGbFIgUJpLp+XeIR65v8ra7WuJOFUBtkMA==",
+      "requires": {
+        "find-up": "^3.0.0"
+      }
+    },
     "pkginfo": {
       "version": "0.4.1",
       "resolved": "https://registry.npmjs.org/pkginfo/-/pkginfo-0.4.1.tgz",
@@ -2536,8 +2657,7 @@
     "punycode": {
       "version": "2.1.1",
       "resolved": "https://registry.npmjs.org/punycode/-/punycode-2.1.1.tgz",
-      "integrity": "sha1-tYsBCsQMIsVldhbI0sLALHv0eew=",
-      "dev": true
+      "integrity": "sha1-tYsBCsQMIsVldhbI0sLALHv0eew="
     },
     "qs": {
       "version": "6.5.2",
@@ -3156,7 +3276,6 @@
       "version": "4.2.2",
       "resolved": "https://registry.npmjs.org/uri-js/-/uri-js-4.2.2.tgz",
       "integrity": "sha1-lMVA4f93KVbiKZUHwBCupsiDjrA=",
-      "dev": true,
       "requires": {
         "punycode": "^2.1.0"
       }
diff --git a/package.json b/package.json
index 8865d5bf..7f491885 100644
--- a/package.json
+++ b/package.json
@@ -10,6 +10,7 @@
   "license": "GPL-3.0",
   "dependencies": {
     "chokidar": "^3.4.1",
+    "electron-store": "^6.0.0",
     "jquery": "^3.5.1",
     "reflect-metadata": "^0.1.13"
   },
diff --git a/src/ide/project.ts b/src/ide/project.ts
index 68df4ec1..0bde64ba 100644
--- a/src/ide/project.ts
+++ b/src/ide/project.ts
@@ -8,6 +8,10 @@ type BuildStatusCallback = (busy:boolean) => void;
 type IterateFilesCallback = (path:string, data:FileData) => void;
 type GetRemoteCallback = (path:string, callback:(data:FileData) => void, datatype:'text'|'arraybuffer') => any;
 
+function isEmptyString(text : FileData) {
+  return typeof text == 'string' && text.trim && text.trim().length == 0;
+}
+
 export class CodeProject {
   filedata : {[path:string]:FileData} = {};
   listings : CodeListingMap;
@@ -26,6 +30,7 @@ export class CodeProject {
   callbackGetRemote : GetRemoteCallback;
   isCompiling : boolean = false;
   filename2path = {}; // map stripped paths to full paths
+  persistent : boolean = true; // set to true and won't modify store
 
   constructor(worker, platform_id:string, platform, store) {
     this.worker = worker;
@@ -149,7 +154,7 @@ export class CodeProject {
 
   updateFileInStore(path:string, text:FileData) {
     // protect against accidential whole-file deletion
-    if (text instanceof Uint8Array || ((<string>text).trim && (<string>text).trim().length)) {
+    if (this.persistent && !isEmptyString(text)) {
       this.store.setItem(path, text);
     }
   }
@@ -228,7 +233,7 @@ export class CodeProject {
                 } else {
                   if (data instanceof ArrayBuffer)
                     data = new Uint8Array(data); // convert to typed array
-                  console.log("GET",webpath,data.length,'bytes');
+                  console.log("read",webpath,data.length,'bytes');
                   this.filedata[path] = data; // do not update store, just cache
                   addResult(path, data);
                 }
diff --git a/src/ide/ui.ts b/src/ide/ui.ts
index 5091fd3e..8d38a955 100644
--- a/src/ide/ui.ts
+++ b/src/ide/ui.ts
@@ -168,7 +168,13 @@ function unsetLastPreset() {
 function initProject() {
   current_project = new CodeProject(newWorker(), platform_id, platform, store);
   projectWindows = new ProjectWindows($("#workspace")[0] as HTMLElement, current_project);
-  current_project.callbackGetRemote = getWithBinary;
+  if (qs['electron_ws']) {
+    current_project.callbackGetRemote = getElectronFile;
+    current_project.persistent = false;
+    // TODO: save file when edited
+  } else {
+    current_project.callbackGetRemote = getWithBinary;
+  }
   current_project.callbackBuildResult = (result:WorkerResult) => {
     setCompileOutput(result);
     refreshWindowList();
@@ -1044,7 +1050,9 @@ async function updateSelector() {
     await populateFiles(sel, "Local Files", "", foundFiles);
     finishSelector(sel);
   } else {
-    sel.append($("<option />").val('/').text('Leave Repository'));
+    if (!qs['electron_ws']) {
+      sel.append($("<option />").val('/').text('Leave Repository'));
+    }
     $("#repo_name").text(getFilenameForPath(repo_id)+'/').show();
     // repo: populate all files
     await populateFiles(sel, repo_id, "", {});
@@ -2193,7 +2201,20 @@ function redirectToHTTPS() {
 // redirect to HTTPS after script loads?
 redirectToHTTPS();
 
-// listen for messages
-window.onmessage = function(event) {
-  console.log("WINDOW", event);
-};
+//// ELECTRON STUFF
+
+// get remote file from local fs
+declare var getWorkspaceFile;
+export function getElectronFile(url:string, success:(text:string|Uint8Array)=>void, datatype:'text'|'arraybuffer') {
+  // TODO: we have to split() to strip off presets/platform, yukky
+  var contents = getWorkspaceFile(url.split('/',3)[2], datatype);
+  if (contents != null) {
+    success(contents); // return result
+  } else {
+    getWithBinary(url, success, datatype); // try to load from presets/platform via GET
+  }
+}
+export function reloadWorkspaceFile(path: string) {
+  var datatype = typeof current_project.filedata[path] == 'string' ? 'text' : 'arraybuffer';
+  projectWindows.updateFile(path, getWorkspaceFile(path, datatype));
+}