diff --git a/CHANGELOG.md b/CHANGELOG.md
index ab5b3cb9f..65f75ee18 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,8 @@
 
 ## Current Master
 
+- Fix bug where web3 API was sometimes injected after the page loaded.
+
 ## 3.11.0 2017-10-11
 
 - Add support for new eth_signTypedData method per EIP 712.
diff --git a/app/scripts/contentscript.js b/app/scripts/contentscript.js
index b4708189e..ffbbc73cc 100644
--- a/app/scripts/contentscript.js
+++ b/app/scripts/contentscript.js
@@ -7,7 +7,9 @@ const ObjectMultiplex = require('obj-multiplex')
 const extension = require('extensionizer')
 const PortStream = require('./lib/port-stream.js')
 
-const inpageText = fs.readFileSync(path.join(__dirname, 'inpage.js')).toString()
+const inpageContent = fs.readFileSync(path.join(__dirname, '..', '..', 'dist', 'chrome', 'scripts', 'inpage.js')).toString()
+const inpageSuffix = '//# sourceURL=' + extension.extension.getURL('scripts/inpage.js') + '\n'
+const inpageBundle = inpageContent + inpageSuffix
 
 // Eventually this streaming injection could be replaced with:
 // https://developer.mozilla.org/en-US/docs/Mozilla/Tech/XPCOM/Language_Bindings/Components.utils.exportFunction
@@ -25,8 +27,7 @@ function setupInjection () {
   try {
     // inject in-page script
     var scriptTag = document.createElement('script')
-    scriptTag.src = extension.extension.getURL('scripts/inpage.js')
-    scriptTag.textContent = inpageText
+    scriptTag.textContent = inpageBundle
     scriptTag.onload = function () { this.parentNode.removeChild(this) }
     var container = document.head || document.documentElement
     // append as first child
diff --git a/gulpfile.js b/gulpfile.js
index 557b58a68..9253949c7 100644
--- a/gulpfile.js
+++ b/gulpfile.js
@@ -186,8 +186,13 @@ jsFiles.forEach((jsFile) => {
   gulp.task(`build:js:${jsFile}`, bundleTask({ watch: false, label: jsFile, filename: `${jsFile}.js` }))
 })
 
-gulp.task('dev:js', gulp.parallel(...jsDevStrings))
-gulp.task('build:js',  gulp.parallel(...jsBuildStrings))
+// inpage must be built before all other scripts:
+const firstDevString = jsDevStrings.shift()
+gulp.task('dev:js', gulp.series(firstDevString, gulp.parallel(...jsDevStrings)))
+
+// inpage must be built before all other scripts:
+const firstBuildString = jsBuildStrings.shift()
+gulp.task('build:js',  gulp.series(firstBuildString, gulp.parallel(...jsBuildStrings)))
 
 // disc bundle analyzer tasks