diff --git a/spec/style-manager-spec.coffee b/spec/style-manager-spec.coffee
deleted file mode 100644
index d0a1cfe13..000000000
--- a/spec/style-manager-spec.coffee
+++ /dev/null
@@ -1,68 +0,0 @@
-StyleManager = require '../src/style-manager'
-
-describe "StyleManager", ->
-  [manager, addEvents, removeEvents, updateEvents] = []
-
-  beforeEach ->
-    manager = new StyleManager(configDirPath: atom.getConfigDirPath())
-    addEvents = []
-    removeEvents = []
-    updateEvents = []
-
-    manager.onDidAddStyleElement (event) -> addEvents.push(event)
-    manager.onDidRemoveStyleElement (event) -> removeEvents.push(event)
-    manager.onDidUpdateStyleElement (event) -> updateEvents.push(event)
-
-  describe "::addStyleSheet(source, params)", ->
-    it "adds a stylesheet based on the given source and returns a disposable allowing it to be removed", ->
-      disposable = manager.addStyleSheet("a {color: red;}")
-
-      expect(addEvents.length).toBe 1
-      expect(addEvents[0].textContent).toBe "a {color: red;}"
-
-      styleElements = manager.getStyleElements()
-      expect(styleElements.length).toBe 1
-      expect(styleElements[0].textContent).toBe "a {color: red;}"
-
-      disposable.dispose()
-
-      expect(removeEvents.length).toBe 1
-      expect(removeEvents[0].textContent).toBe "a {color: red;}"
-      expect(manager.getStyleElements().length).toBe 0
-
-    describe "when a sourcePath parameter is specified", ->
-      it "ensures a maximum of one style element for the given source path, updating a previous if it exists", ->
-        disposable1 = manager.addStyleSheet("a {color: red;}", sourcePath: '/foo/bar')
-
-        expect(addEvents.length).toBe 1
-        expect(addEvents[0].getAttribute('source-path')).toBe '/foo/bar'
-
-        disposable2 = manager.addStyleSheet("a {color: blue;}", sourcePath: '/foo/bar')
-
-        expect(addEvents.length).toBe 1
-        expect(updateEvents.length).toBe 1
-        expect(updateEvents[0].getAttribute('source-path')).toBe '/foo/bar'
-        expect(updateEvents[0].textContent).toBe "a {color: blue;}"
-
-        disposable2.dispose()
-        addEvents = []
-
-        manager.addStyleSheet("a {color: yellow;}", sourcePath: '/foo/bar')
-
-        expect(addEvents.length).toBe 1
-        expect(addEvents[0].getAttribute('source-path')).toBe '/foo/bar'
-        expect(addEvents[0].textContent).toBe "a {color: yellow;}"
-
-    describe "when a priority parameter is specified", ->
-      it "inserts the style sheet based on the priority", ->
-        manager.addStyleSheet("a {color: red}", priority: 1)
-        manager.addStyleSheet("a {color: blue}", priority: 0)
-        manager.addStyleSheet("a {color: green}", priority: 2)
-        manager.addStyleSheet("a {color: yellow}", priority: 1)
-
-        expect(manager.getStyleElements().map (elt) -> elt.textContent).toEqual [
-          "a {color: blue}"
-          "a {color: red}"
-          "a {color: yellow}"
-          "a {color: green}"
-        ]
diff --git a/spec/style-manager-spec.js b/spec/style-manager-spec.js
new file mode 100644
index 000000000..19451ffea
--- /dev/null
+++ b/spec/style-manager-spec.js
@@ -0,0 +1,66 @@
+const StyleManager = require('../src/style-manager')
+
+describe('StyleManager', () => {
+  let [manager, addEvents, removeEvents, updateEvents] = []
+
+  beforeEach(() => {
+    manager = new StyleManager({configDirPath: atom.getConfigDirPath()})
+    addEvents = []
+    removeEvents = []
+    updateEvents = []
+    manager.onDidAddStyleElement((event) => { addEvents.push(event) })
+    manager.onDidRemoveStyleElement((event) => { removeEvents.push(event) })
+    manager.onDidUpdateStyleElement((event) => { updateEvents.push(event) })
+  })
+
+  describe('::addStyleSheet(source, params)', () => {
+    it('adds a stylesheet based on the given source and returns a disposable allowing it to be removed', () => {
+      const disposable = manager.addStyleSheet('a {color: red}')
+      expect(addEvents.length).toBe(1)
+      expect(addEvents[0].textContent).toBe('a {color: red}')
+      const styleElements = manager.getStyleElements()
+      expect(styleElements.length).toBe(1)
+      expect(styleElements[0].textContent).toBe('a {color: red}')
+      disposable.dispose()
+      expect(removeEvents.length).toBe(1)
+      expect(removeEvents[0].textContent).toBe('a {color: red}')
+      expect(manager.getStyleElements().length).toBe(0)
+    })
+
+    describe('when a sourcePath parameter is specified', () => {
+      it('ensures a maximum of one style element for the given source path, updating a previous if it exists', () => {
+        const disposable1 = manager.addStyleSheet('a {color: red}', {sourcePath: '/foo/bar'})
+        expect(addEvents.length).toBe(1)
+        expect(addEvents[0].getAttribute('source-path')).toBe('/foo/bar')
+
+        const disposable2 = manager.addStyleSheet('a {color: blue}', {sourcePath: '/foo/bar'})
+        expect(addEvents.length).toBe(1)
+        expect(updateEvents.length).toBe(1)
+        expect(updateEvents[0].getAttribute('source-path')).toBe('/foo/bar')
+        expect(updateEvents[0].textContent).toBe('a {color: blue}')
+        disposable2.dispose()
+
+        addEvents = []
+        manager.addStyleSheet('a {color: yellow}', {sourcePath: '/foo/bar'})
+        expect(addEvents.length).toBe(1)
+        expect(addEvents[0].getAttribute('source-path')).toBe('/foo/bar')
+        expect(addEvents[0].textContent).toBe('a {color: yellow}')
+      })
+    })
+
+    describe('when a priority parameter is specified', () => {
+      it('inserts the style sheet based on the priority', () => {
+        manager.addStyleSheet('a {color: red}', {priority: 1})
+        manager.addStyleSheet('a {color: blue}', {priority: 0})
+        manager.addStyleSheet('a {color: green}', {priority: 2})
+        manager.addStyleSheet('a {color: yellow}', {priority: 1})
+        expect(manager.getStyleElements().map((elt) => elt.textContent)).toEqual([
+          'a {color: blue}',
+          'a {color: red}',
+          'a {color: yellow}',
+          'a {color: green}'
+        ])
+      })
+    })
+  })
+})