diff --git a/.travis.yml b/.travis.yml
index 43f66ebf..62c3c98e 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -11,7 +11,7 @@ jobs:
   include:
     - stage: test
       script:
-        - yarn run prettier
+        - yarn run prettier-check
         - yarn run typecheck
         - yarn run tslint
         - yarn run build
diff --git a/.vscode/extensions.json b/.vscode/extensions.json
index 10e7c486..4e699121 100644
--- a/.vscode/extensions.json
+++ b/.vscode/extensions.json
@@ -1,3 +1,3 @@
 {
-  "recommendations": ["esbenp.prettier-vscode", "EditorConfig.EditorConfig"]
+  "recommendations": ["esbenp.prettier-vscode", "EditorConfig.EditorConfig"],
 }
diff --git a/.vscode/settings.json b/.vscode/settings.json
index 53b9d213..aaaa1722 100644
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -4,6 +4,6 @@
     "**/node_modules": true,
     "**/bower_components": true,
     "lib/": true,
-    "coverage/": true
-  }
+    "coverage/": true,
+  },
 }
diff --git a/.vscode/tasks.json b/.vscode/tasks.json
index 3e0de787..d83f7b36 100644
--- a/.vscode/tasks.json
+++ b/.vscode/tasks.json
@@ -2,5 +2,5 @@
   // See https://go.microsoft.com/fwlink/?LinkId=733558
   // for the documentation about the tasks.json format
   "version": "2.0.0",
-  "tasks": []
+  "tasks": [],
 }
diff --git a/package.json b/package.json
index baa61313..06efff80 100644
--- a/package.json
+++ b/package.json
@@ -15,6 +15,7 @@
   "scripts": {
     "semantic-release": "semantic-release",
     "prettier": "prettier '**/{*.{js?(on),ts?(x),scss,yml},.*.js?(on),.*.yml}' --write --list-different",
+    "prettier-check": "npm run prettier -- --write=false",
     "typecheck": "tsc -p tsconfig.json",
     "tslint": "tslint -c tslint.json -p tsconfig.json './src/*.ts?(x)' './testdata/*.ts?(x)' './*.ts?(x)'",
     "build": "yarn run tsc && cpy 'src/**/*.scss' lib/",
diff --git a/src/hoverifier.ts b/src/hoverifier.ts
index e0cfa2b3..629ba401 100644
--- a/src/hoverifier.ts
+++ b/src/hoverifier.ts
@@ -433,25 +433,24 @@ export function createHoverifier<C extends object, D, A>({
         debounceTime(MOUSEOVER_DELAY),
         // Do not consider mouseovers while overlay is pinned
         filter(() => !container.values.hoverOverlayIsFixed),
-        switchMap(
-            ({ adjustPosition, codeView, resolveContext, position, ...rest }) =>
-                adjustPosition && position
-                    ? from(
-                          adjustPosition({
-                              codeView,
-                              position: { ...position, ...resolveContext(position) },
-                              direction: AdjustmentDirection.CodeViewToActual,
-                          })
-                      ).pipe(
-                          map(({ line, character }) => ({
-                              codeView,
-                              resolveContext,
-                              position: { ...position, line, character },
-                              adjustPosition,
-                              ...rest,
-                          }))
-                      )
-                    : of({ adjustPosition, codeView, resolveContext, position, ...rest })
+        switchMap(({ adjustPosition, codeView, resolveContext, position, ...rest }) =>
+            adjustPosition && position
+                ? from(
+                      adjustPosition({
+                          codeView,
+                          position: { ...position, ...resolveContext(position) },
+                          direction: AdjustmentDirection.CodeViewToActual,
+                      })
+                  ).pipe(
+                      map(({ line, character }) => ({
+                          codeView,
+                          resolveContext,
+                          position: { ...position, line, character },
+                          adjustPosition,
+                          ...rest,
+                      }))
+                  )
+                : of({ adjustPosition, codeView, resolveContext, position, ...rest })
         ),
         share()
     )
@@ -462,25 +461,24 @@ export function createHoverifier<C extends object, D, A>({
             target: event.target as HTMLElement,
             ...rest,
         })),
-        switchMap(
-            ({ adjustPosition, codeView, resolveContext, position, ...rest }) =>
-                adjustPosition && position
-                    ? from(
-                          adjustPosition({
-                              codeView,
-                              position: { ...position, ...resolveContext(position) },
-                              direction: AdjustmentDirection.CodeViewToActual,
-                          })
-                      ).pipe(
-                          map(({ line, character }) => ({
-                              codeView,
-                              resolveContext,
-                              position: { ...position, line, character },
-                              adjustPosition,
-                              ...rest,
-                          }))
-                      )
-                    : of({ adjustPosition, codeView, resolveContext, position, ...rest })
+        switchMap(({ adjustPosition, codeView, resolveContext, position, ...rest }) =>
+            adjustPosition && position
+                ? from(
+                      adjustPosition({
+                          codeView,
+                          position: { ...position, ...resolveContext(position) },
+                          direction: AdjustmentDirection.CodeViewToActual,
+                      })
+                  ).pipe(
+                      map(({ line, character }) => ({
+                          codeView,
+                          resolveContext,
+                          position: { ...position, line, character },
+                          adjustPosition,
+                          ...rest,
+                      }))
+                  )
+                : of({ adjustPosition, codeView, resolveContext, position, ...rest })
         ),
         share()
     )
@@ -583,9 +581,8 @@ export function createHoverifier<C extends object, D, A>({
                             : target,
                     ...rest,
                 })),
-                map(
-                    ({ hoverOverlayElement, relativeElement, target }) =>
-                        target ? calculateOverlayPosition({ relativeElement, target, hoverOverlayElement }) : undefined
+                map(({ hoverOverlayElement, relativeElement, target }) =>
+                    target ? calculateOverlayPosition({ relativeElement, target, hoverOverlayElement }) : undefined
                 )
             )
             .subscribe(hoverOverlayPosition => {
diff --git a/src/token_position.ts b/src/token_position.ts
index 7ef158e1..04ab2c98 100644
--- a/src/token_position.ts
+++ b/src/token_position.ts
@@ -482,7 +482,7 @@ export const getTokenAtPosition = (
         isFirstCharacterDiffIndicator,
     }: Pick<DOMFunctions, 'getCodeElementFromLineNumber' | 'isFirstCharacterDiffIndicator'>,
     part?: DiffPart,
-    tokenize = true,
+    tokenize = true
 ): HTMLElement | undefined => {
     const codeElement = getCodeElementFromLineNumber(codeView, line, part)
     if (!codeElement) {
diff --git a/tsconfig.dist.json b/tsconfig.dist.json
index 7ddf5084..f85e3f9e 100644
--- a/tsconfig.dist.json
+++ b/tsconfig.dist.json
@@ -5,8 +5,8 @@
     "declaration": true,
     "declarationMap": true,
     "inlineSourceMap": true,
-    "inlineSources": true
+    "inlineSources": true,
   },
   "include": ["src/**/*"],
-  "exclude": ["src/**/*.test.ts", "src/testutils"]
+  "exclude": ["src/**/*.test.ts", "src/testutils"],
 }
diff --git a/tsconfig.json b/tsconfig.json
index 762d8e72..116c4b69 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -9,6 +9,6 @@
     "outDir": "lib",
     "allowSyntheticDefaultImports": true,
     "esModuleInterop": true,
-    "lib": ["es2017", "dom", "dom.iterable"]
-  }
+    "lib": ["es2017", "dom", "dom.iterable"],
+  },
 }