diff --git a/packages/gatsby/index.d.ts b/packages/gatsby/index.d.ts
index d478e22d2b4ba..21b18bab5bd17 100644
--- a/packages/gatsby/index.d.ts
+++ b/packages/gatsby/index.d.ts
@@ -34,7 +34,9 @@ export const graphql: (query: TemplateStringsArray) => void
  */
 export interface GatsbyConfig {
   siteMetadata?: Record<string, unknown>
-  plugins?: Array<string | {
+  plugins?: Array<
+    | string
+    | {
         resolve: string
         options: Record<string, unknown>
       }
@@ -53,7 +55,11 @@ export interface GatsbyConfig {
 type AnyOrPromiseAny = any | Promise<any>
 
 // all available gatsby stages
-type GatsbyStages = "develop" | "develop-html" | "build-javascript" | "build-html"
+type GatsbyStages =
+  | "develop"
+  | "develop-html"
+  | "build-javascript"
+  | "build-html"
 
 /**
  * Gatsby API for Node.js.
@@ -61,157 +67,156 @@ type GatsbyStages = "develop" | "develop-html" | "build-javascript" | "build-htm
  * @see https://www.gatsbyjs.org/docs/node-apis/
  */
 export interface GatsbyNode {
-  createPages?: (
-    args: CreatePagesArgs & { traceId: "initial-createPages" },
-    options: PluginOptions
-  ) => AnyOrPromiseAny
-  createPages?: (
-    args: CreatePagesArgs & { traceId: "initial-createPages" },
-    options: PluginOptions,
-    callback: PluginCallback
-  ) => void
-
-  createPagesStatefully?: (
-    args: CreatePagesArgs & { traceId: "initial-createPagesStatefully" },
-    options: PluginOptions
-  ) => AnyOrPromiseAny
-  createPagesStatefully?: (
-    args: CreatePagesArgs & { traceId: "initial-createPagesStatefully" },
-    options: PluginOptions,
-    callback: PluginCallback
-  ) => void
-
-  onCreateBabelConfig?: (
-    args: CreateBabelConfigArgs,
-    options: PluginOptions
-  ) => AnyOrPromiseAny
-  onCreateBabelConfig?: (
-    args: CreateBabelConfigArgs,
-    options: PluginOptions,
-    callback: PluginCallback
-  ) => void
-
-  onCreateDevServer?: (
-    args: CreateDevServerArgs,
-    options: PluginOptions
-  ) => AnyOrPromiseAny
-  onCreateDevServer?: (
-    args: CreateDevServerArgs,
-    options: PluginOptions,
-    callback: PluginCallback
-  ) => void
-
-  onCreateNode?: (args: CreateNodeArgs, options: PluginOptions) => AnyOrPromiseAny
-  onCreateNode?: (
-    args: CreateNodeArgs,
-    options: PluginOptions,
-    callback: PluginCallback
-  ) => void
-
-  onCreatePage?: (args: CreatePageArgs, options: PluginOptions) => AnyOrPromiseAny
-  onCreatePage?: (
-    args: CreatePageArgs,
-    options: PluginOptions,
-    callback: PluginCallback
-  ) => void
-
-  onCreateWebpackConfig?: (
-    args: CreateWebpackConfigArgs,
-    options: PluginOptions
-  ) => AnyOrPromiseAny
-  onCreateWebpackConfig?: (
-    args: CreateWebpackConfigArgs,
-    options: PluginOptions,
-    callback: PluginCallback
-  ) => void
-
-  onPostBootstrap?: (args: ParentSpanPluginArgs, options: PluginOptions) => AnyOrPromiseAny
-  onPostBootstrap?: (
-    args: ParentSpanPluginArgs,
-    options: PluginOptions,
-    callback: PluginCallback
-  ) => void
-
-  onPostBuild?: (args: BuildArgs, options: PluginOptions) => AnyOrPromiseAny
-  onPostBuild?: (
-    args: BuildArgs,
-    options: PluginOptions,
-    callback: PluginCallback
-  ) => void
-
-  onPreBootstrap?: (
-    args: ParentSpanPluginArgs,
-    options: PluginOptions
-  ) => AnyOrPromiseAny
-  onPreBootstrap?: (
-    args: ParentSpanPluginArgs,
-    options: PluginOptions,
-    callback: PluginCallback
-  ) => void
-
-  onPreBuild?: (args: BuildArgs, options: PluginOptions) => AnyOrPromiseAny
-  onPreBuild?: (
-    args: BuildArgs,
-    options: PluginOptions,
-    callback: PluginCallback
-  ) => void
-
-  onPreExtractQueries?: (
-    args: ParentSpanPluginArgs,
-    options: PluginOptions
-  ) => AnyOrPromiseAny
-  onPreExtractQueries?: (
-    args: ParentSpanPluginArgs,
-    options: PluginOptions,
-    callback: PluginCallback
-  ) => void
-
-  onPreInit?: (
-    args: ParentSpanPluginArgs,
-    options: PluginOptions
-  ) => AnyOrPromiseAny
-  onPreInit?: (
-    args: ParentSpanPluginArgs,
-    options: PluginOptions,
-    callback: PluginCallback
-  ) => void
-
-  preprocessSource?: (
-    args: PreprocessSourceArgs,
-    options: PluginOptions
-  ) => AnyOrPromiseAny
-  preprocessSource?: (
-    args: PreprocessSourceArgs,
-    options: PluginOptions,
-    callback: PluginCallback
-  ) => void
-
-  resolvableExtensions?: (
-    args: ResolvableExtensionsArgs,
-    options: PluginOptions
-  ) => AnyOrPromiseAny
-  resolvableExtensions?: (
-    args: ResolvableExtensionsArgs,
-    options: PluginOptions,
-    callback: PluginCallback
-  ) => void
-
-  setFieldsOnGraphQLNodeType?: (
-    args: SetFieldsOnGraphQLNodeTypeArgs,
-    options: PluginOptions
-  ) => AnyOrPromiseAny
-  setFieldsOnGraphQLNodeType?: (
-    args: SetFieldsOnGraphQLNodeTypeArgs,
-    options: PluginOptions,
-    callback: PluginCallback
-  ) => void
-
-  sourceNodes?: (args: SourceNodesArgs, options: PluginOptions) => AnyOrPromiseAny
-  sourceNodes?: (
-    args: SourceNodesArgs,
-    options: PluginOptions,
-    callback: PluginCallback
-  ) => void
+  createPages?:
+    | ((
+        args: CreatePagesArgs & { traceId: "initial-createPages" },
+        options: PluginOptions
+      ) => AnyOrPromiseAny)
+    | ((
+        args: CreatePagesArgs & { traceId: "initial-createPages" },
+        options: PluginOptions,
+        callback: PluginCallback
+      ) => void)
+
+  createPagesStatefully?:
+    | ((
+        args: CreatePagesArgs & { traceId: "initial-createPagesStatefully" },
+        options: PluginOptions
+      ) => AnyOrPromiseAny)
+    | ((
+        args: CreatePagesArgs & { traceId: "initial-createPagesStatefully" },
+        options: PluginOptions,
+        callback: PluginCallback
+      ) => void)
+
+  onCreateBabelConfig?:
+    | ((args: CreateBabelConfigArgs, options: PluginOptions) => AnyOrPromiseAny)
+    | ((
+        args: CreateBabelConfigArgs,
+        options: PluginOptions,
+        callback: PluginCallback
+      ) => void)
+
+  onCreateDevServer?:
+    | ((args: CreateDevServerArgs, options: PluginOptions) => AnyOrPromiseAny)
+    | ((
+        args: CreateDevServerArgs,
+        options: PluginOptions,
+        callback: PluginCallback
+      ) => void)
+
+  onCreateNode?:
+    | ((args: CreateNodeArgs, options: PluginOptions) => AnyOrPromiseAny)
+    | ((
+        args: CreateNodeArgs,
+        options: PluginOptions,
+        callback: PluginCallback
+      ) => void)
+
+  onCreatePage?:
+    | ((args: CreatePageArgs, options: PluginOptions) => AnyOrPromiseAny)
+    | ((
+        args: CreatePageArgs,
+        options: PluginOptions,
+        callback: PluginCallback
+      ) => void)
+
+  onCreateWebpackConfig?:
+    | ((
+        args: CreateWebpackConfigArgs,
+        options: PluginOptions
+      ) => AnyOrPromiseAny)
+    | ((
+        args: CreateWebpackConfigArgs,
+        options: PluginOptions,
+        callback: PluginCallback
+      ) => void)
+
+  onPostBootstrap?:
+    | ((args: ParentSpanPluginArgs, options: PluginOptions) => AnyOrPromiseAny)
+    | ((
+        args: ParentSpanPluginArgs,
+        options: PluginOptions,
+        callback: PluginCallback
+      ) => void)
+
+  onPostBuild?:
+    | ((args: BuildArgs, options: PluginOptions) => AnyOrPromiseAny)
+    | ((
+        args: BuildArgs,
+        options: PluginOptions,
+        callback: PluginCallback
+      ) => void)
+
+  onPreBootstrap?:
+    | ((args: ParentSpanPluginArgs, options: PluginOptions) => AnyOrPromiseAny)
+    | ((
+        args: ParentSpanPluginArgs,
+        options: PluginOptions,
+        callback: PluginCallback
+      ) => void)
+
+  onPreBuild?:
+    | ((args: BuildArgs, options: PluginOptions) => AnyOrPromiseAny)
+    | ((
+        args: BuildArgs,
+        options: PluginOptions,
+        callback: PluginCallback
+      ) => void)
+
+  onPreExtractQueries?:
+    | ((args: ParentSpanPluginArgs, options: PluginOptions) => AnyOrPromiseAny)
+    | ((
+        args: ParentSpanPluginArgs,
+        options: PluginOptions,
+        callback: PluginCallback
+      ) => void)
+
+  onPreInit?:
+    | ((args: ParentSpanPluginArgs, options: PluginOptions) => AnyOrPromiseAny)
+    | ((
+        args: ParentSpanPluginArgs,
+        options: PluginOptions,
+        callback: PluginCallback
+      ) => void)
+
+  preprocessSource?:
+    | ((args: PreprocessSourceArgs, options: PluginOptions) => AnyOrPromiseAny)
+    | ((
+        args: PreprocessSourceArgs,
+        options: PluginOptions,
+        callback: PluginCallback
+      ) => void)
+
+  resolvableExtensions?:
+    | ((
+        args: ResolvableExtensionsArgs,
+        options: PluginOptions
+      ) => AnyOrPromiseAny)
+    | ((
+        args: ResolvableExtensionsArgs,
+        options: PluginOptions,
+        callback: PluginCallback
+      ) => void)
+
+  setFieldsOnGraphQLNodeType?:
+    | ((
+        args: SetFieldsOnGraphQLNodeTypeArgs,
+        options: PluginOptions
+      ) => AnyOrPromiseAny)
+    | ((
+        args: SetFieldsOnGraphQLNodeTypeArgs,
+        options: PluginOptions,
+        callback: PluginCallback
+      ) => void)
+
+  sourceNodes?:
+    | ((args: SourceNodesArgs, options: PluginOptions) => AnyOrPromiseAny)
+    | ((
+        args: SourceNodesArgs,
+        options: PluginOptions,
+        callback: PluginCallback
+      ) => void)
 }
 
 /**
@@ -220,23 +225,38 @@ export interface GatsbyNode {
  * @see https://www.gatsbyjs.org/docs/browser-apis/
  */
 export interface GatsbyBrowser {
-  disableCorePrefetching?: (args: BrowserPluginArgs, options: PluginOptions) => any
+  disableCorePrefetching?: (
+    args: BrowserPluginArgs,
+    options: PluginOptions
+  ) => any
   onClientEntry?: (args: BrowserPluginArgs, options: PluginOptions) => any
-  onInitialClientRender?: (args: BrowserPluginArgs, options: PluginOptions) => any
+  onInitialClientRender?: (
+    args: BrowserPluginArgs,
+    options: PluginOptions
+  ) => any
   onPostPrefetchPathname?: (
     args: PrefetchPathnameArgs,
     options: PluginOptions
   ) => any
   onPreRouteUpdate?: (args: RouteUpdateArgs, options: PluginOptions) => any
-  onPrefetchPathname?: (args: PrefetchPathnameArgs, options: PluginOptions) => any
+  onPrefetchPathname?: (
+    args: PrefetchPathnameArgs,
+    options: PluginOptions
+  ) => any
   onRouteUpdate?: (args: RouteUpdateArgs, options: PluginOptions) => any
-  onRouteUpdateDelayed?: (args: RouteUpdateDelayedArgs, options: PluginOptions) => any
-  onServiceWorkerActive?: (args: ServiceWorkerArgs, options: PluginOptions) => any
+  onRouteUpdateDelayed?: (
+    args: RouteUpdateDelayedArgs,
+    options: PluginOptions
+  ) => any
+  onServiceWorkerActive?: (
+    args: ServiceWorkerArgs,
+    options: PluginOptions
+  ) => any
   onServiceWorkerInstalled?: (
     args: ServiceWorkerArgs,
     options: PluginOptions
   ) => any
-  onServiceWorkerRedundant?:(
+  onServiceWorkerRedundant?: (
     args: ServiceWorkerArgs,
     options: PluginOptions
   ) => any
@@ -244,18 +264,27 @@ export interface GatsbyBrowser {
     args: ServiceWorkerArgs,
     options: PluginOptions
   ) => any
-  registerServiceWorker?: (args: BrowserPluginArgs, options: PluginOptions) => any
+  registerServiceWorker?: (
+    args: BrowserPluginArgs,
+    options: PluginOptions
+  ) => any
   replaceComponentRenderer?: (
     args: ReplaceComponentRendererArgs,
     options: PluginOptions
   ) => any
-  replaceHydrateFunction?: (args: BrowserPluginArgs, options: PluginOptions) => any
-  shouldUpdateScroll?: (args: ShouldUpdateScrollArgs, options: PluginOptions) => any
+  replaceHydrateFunction?: (
+    args: BrowserPluginArgs,
+    options: PluginOptions
+  ) => any
+  shouldUpdateScroll?: (
+    args: ShouldUpdateScrollArgs,
+    options: PluginOptions
+  ) => any
   wrapPageElement?: (
     args: WrapPageElementBrowserArgs,
     options: PluginOptions
   ) => any
-  wrapRootElement: ?(
+  wrapRootElement?: (
     args: WrapRootElementBrowserArgs,
     options: PluginOptions
   ) => any
@@ -267,40 +296,51 @@ export interface GatsbyBrowser {
  * @see https://www.gatsbyjs.org/docs/ssr-apis/
  */
 export interface GatsbySSR {
-  onPreRenderHTML?: (args: PreRenderHTMLArgs, options: PluginOptions) => AnyOrPromiseAny
-  onPreRenderHTML?: (
-    args: PreRenderHTMLArgs,
-    options: PluginOptions,
-    callback: PluginCallback
-  ) => void
-
-  onRenderBody?: (args: RenderBodyArgs, options: PluginOptions) => AnyOrPromiseAny
-  onRenderBody?: (
-    args: RenderBodyArgs,
-    options: PluginOptions,
-    callback: PluginCallback
-  ) => void
-
-  replaceRenderer?: (args: ReplaceRendererArgs, options: PluginOptions) => AnyOrPromiseAny
-  replaceRenderer?: (
-    args: ReplaceRendererArgs,
-    options: PluginOptions,
-    callback: PluginCallback
-  ) => void
-
-  wrapPageElement?: (args: WrapPageElementNodeArgs, options: PluginOptions) => AnyOrPromiseAny
-  wrapPageElement?: (
-    args: WrapPageElementNodeArgs,
-    options: PluginOptions,
-    callback: PluginCallback
-  ) => void
-
-  wrapRootElement?: (args: WrapRootElementNodeArgs, options: PluginOptions) => AnyOrPromiseAny
-  wrapRootElement?: (
-    args: WrapRootElementNodeArgs,
-    options: PluginOptions,
-    callback: PluginCallback
-  ) => void
+  onPreRenderHTML?:
+    | ((args: PreRenderHTMLArgs, options: PluginOptions) => AnyOrPromiseAny)
+    | ((
+        args: PreRenderHTMLArgs,
+        options: PluginOptions,
+        callback: PluginCallback
+      ) => void)
+
+  onRenderBody?:
+    | ((args: RenderBodyArgs, options: PluginOptions) => AnyOrPromiseAny)
+    | ((
+        args: RenderBodyArgs,
+        options: PluginOptions,
+        callback: PluginCallback
+      ) => void)
+
+  replaceRenderer?:
+    | ((args: ReplaceRendererArgs, options: PluginOptions) => AnyOrPromiseAny)
+    | ((
+        args: ReplaceRendererArgs,
+        options: PluginOptions,
+        callback: PluginCallback
+      ) => void)
+
+  wrapPageElement?:
+    | ((
+        args: WrapPageElementNodeArgs,
+        options: PluginOptions
+      ) => AnyOrPromiseAny)
+    | ((
+        args: WrapPageElementNodeArgs,
+        options: PluginOptions,
+        callback: PluginCallback
+      ) => void)
+
+  wrapRootElement?:
+    | ((
+        args: WrapRootElementNodeArgs,
+        options: PluginOptions
+      ) => AnyOrPromiseAny)
+    | ((
+        args: WrapRootElementNodeArgs,
+        options: PluginOptions,
+        callback: PluginCallback
+      ) => void)
 }
 
 export interface PluginOptions {
@@ -391,8 +431,8 @@ export interface RenderBodyArgs extends NodePluginArgs {
   setPostBodyComponents: Function
   setBodyProps: Function
   bodyHtml: string
-  scripts: {rel: `preload`, name: chunk}[]
-  styles: {rel: `preload`, name: chunk}[]
+  scripts: { rel: `preload`; name: string }[]
+  styles: { rel: `preload`; name: string }[]
   pathPrefix: string
 }