diff --git a/spec/workspace-element-spec.js b/spec/workspace-element-spec.js
index 228468d26..7564f6931 100644
--- a/spec/workspace-element-spec.js
+++ b/spec/workspace-element-spec.js
@@ -895,27 +895,39 @@ describe('WorkspaceElement', () => {
 
       // No active item. Use first project directory.
       atom.commands.dispatch(workspaceElement, 'window:run-package-specs')
-      expect(ipcRenderer.send).toHaveBeenCalledWith('run-package-specs', path.join(projectPaths[0], 'spec'))
+      expect(ipcRenderer.send).toHaveBeenCalledWith('run-package-specs', path.join(projectPaths[0], 'spec'), {})
       ipcRenderer.send.reset()
 
       // Active item doesn't implement ::getPath(). Use first project directory.
       const item = document.createElement('div')
       atom.workspace.getActivePane().activateItem(item)
       atom.commands.dispatch(workspaceElement, 'window:run-package-specs')
-      expect(ipcRenderer.send).toHaveBeenCalledWith('run-package-specs', path.join(projectPaths[0], 'spec'))
+      expect(ipcRenderer.send).toHaveBeenCalledWith('run-package-specs', path.join(projectPaths[0], 'spec'), {})
       ipcRenderer.send.reset()
 
       // Active item has no path. Use first project directory.
       item.getPath = () => null
       atom.commands.dispatch(workspaceElement, 'window:run-package-specs')
-      expect(ipcRenderer.send).toHaveBeenCalledWith('run-package-specs', path.join(projectPaths[0], 'spec'))
+      expect(ipcRenderer.send).toHaveBeenCalledWith('run-package-specs', path.join(projectPaths[0], 'spec'), {})
       ipcRenderer.send.reset()
 
       // Active item has path. Use project path for item path.
       item.getPath = () => path.join(projectPaths[1], 'a-file.txt')
       atom.commands.dispatch(workspaceElement, 'window:run-package-specs')
-      expect(ipcRenderer.send).toHaveBeenCalledWith('run-package-specs', path.join(projectPaths[1], 'spec'))
+      expect(ipcRenderer.send).toHaveBeenCalledWith('run-package-specs', path.join(projectPaths[1], 'spec'), {})
       ipcRenderer.send.reset()
     })
+
+    it("passes additional options to the spec window", () => {
+      const workspaceElement = atom.workspace.getElement()
+      spyOn(ipcRenderer, 'send')
+
+      const projectPath = temp.mkdirSync('dir1-')
+      atom.project.setPaths([projectPath])
+      workspaceElement.runPackageSpecs({env: {ATOM_GITHUB_BABEL_ENV: 'coverage'}})
+
+      expect(ipcRenderer.send).toHaveBeenCalledWith(
+        'run-package-specs', path.join(projectPath, 'spec'), {env: {ATOM_GITHUB_BABEL_ENV: 'coverage'}})
+    })
   })
 })
diff --git a/src/initialize-test-window.coffee b/src/initialize-test-window.coffee
index c6aaada0e..4cbd02bfd 100644
--- a/src/initialize-test-window.coffee
+++ b/src/initialize-test-window.coffee
@@ -24,9 +24,13 @@ module.exports = ({blobStore}) ->
     ApplicationDelegate = require '../src/application-delegate'
     Clipboard = require '../src/clipboard'
     TextEditor = require '../src/text-editor'
+    {updateProcessEnv} = require('./update-process-env')
     require './electron-shims'
 
-    {testRunnerPath, legacyTestRunnerPath, headless, logFile, testPaths} = getWindowLoadSettings()
+    ipcRenderer.on 'environment', (event, env) ->
+      updateProcessEnv(env)
+
+    {testRunnerPath, legacyTestRunnerPath, headless, logFile, testPaths, env} = getWindowLoadSettings()
 
     unless headless
       # Show window synchronously so a focusout doesn't fire on input elements
@@ -59,6 +63,8 @@ module.exports = ({blobStore}) ->
     require('module').globalPaths.push(exportsPath)
     process.env.NODE_PATH = exportsPath # Set NODE_PATH env variable since tasks may need it.
 
+    updateProcessEnv(env)
+
     # Set up optional transpilation for packages under test if any
     FindParentDir = require 'find-parent-dir'
     if packageRoot = FindParentDir.sync(testPaths[0], 'package.json')
diff --git a/src/main-process/atom-application.js b/src/main-process/atom-application.js
index cce859789..a9ff4f731 100644
--- a/src/main-process/atom-application.js
+++ b/src/main-process/atom-application.js
@@ -511,12 +511,12 @@ class AtomApplication extends EventEmitter {
       if (this.applicationMenu) this.applicationMenu.update(window, template, menu)
     }))
 
-    this.disposable.add(ipcHelpers.on(ipcMain, 'run-package-specs', (event, packageSpecPath) => {
-      this.runTests({
+    this.disposable.add(ipcHelpers.on(ipcMain, 'run-package-specs', (event, packageSpecPath, options = {}) => {
+      this.runTests(Object.assign({
         resourcePath: this.devResourcePath,
         pathsToOpen: [packageSpecPath],
         headless: false
-      })
+      }, options))
     }))
 
     this.disposable.add(ipcHelpers.on(ipcMain, 'run-benchmarks', (event, benchmarksPath) => {
@@ -1168,6 +1168,7 @@ class AtomApplication extends EventEmitter {
       env
     })
     this.addWindow(window)
+    if (env) window.replaceEnvironment(env)
     return window
   }
 
diff --git a/src/workspace-element.js b/src/workspace-element.js
index 5531aafdf..f94dbd6e9 100644
--- a/src/workspace-element.js
+++ b/src/workspace-element.js
@@ -310,7 +310,7 @@ class WorkspaceElement extends HTMLElement {
     }
   }
 
-  runPackageSpecs () {
+  runPackageSpecs (options = {}) {
     const activePaneItem = this.model.getActivePaneItem()
     const activePath = activePaneItem && typeof activePaneItem.getPath === 'function' ? activePaneItem.getPath() : null
     let projectPath
@@ -326,7 +326,7 @@ class WorkspaceElement extends HTMLElement {
         specPath = testPath
       }
 
-      ipcRenderer.send('run-package-specs', specPath)
+      ipcRenderer.send('run-package-specs', specPath, options)
     }
   }