diff --git a/index.d.ts b/index.d.ts
index 962ecdd..981a2c8 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1,66 +1,85 @@
-export type Replacer = (this: unknown, key: string, value: unknown) => unknown;
-export type SortKeys = (a: string, b: string) => number;
-export type JSONStringifyable = string | number | boolean | null | object;
+declare namespace writeJsonFile {
+	type Replacer = (this: unknown, key: string, value: any) => unknown;
+	type SortKeys = (a: string, b: string) => number;
+	type JSONStringifyable = string | number | boolean | null | object;
 
-export interface Options {
-	/**
-	 * Indentation as a string or number of spaces. Pass in null for no formatting.
-	 *
-	 * @default '\t'
-	 */
-	readonly indent?: string | number | null;
+	interface Options {
+		/**
+		Indentation as a string or number of spaces. Pass in null for no formatting.
 
-	/**
-	 * Detect indentation automatically if the file exists.
-	 *
-	 * @default false
-	 */
-	readonly detectIndent?: boolean;
+		@default '\t'
+		*/
+		readonly indent?: string | number | null;
 
-	/**
-	 * Sort the keys recursively. Optionally pass in a compare function.
-	 *
-	 * @default false
-	 */
-	readonly sortKeys?: boolean | SortKeys;
+		/**
+		Detect indentation automatically if the file exists.
+
+		@default false
+		*/
+		readonly detectIndent?: boolean;
+
+		/**
+		Sort the keys recursively. Optionally pass in a compare function.
+
+		@default false
+		*/
+		readonly sortKeys?: boolean | SortKeys;
+
+		/**
+		Passed into `JSON.stringify`.
+		*/
+		readonly replacer?: Replacer | Array<number | string>;
+
+		/**
+		Mode used when writing the file.
+
+		@default 0o666
+		*/
+		readonly mode?: number;
+	}
+}
 
+declare const writeJsonFile: {
 	/**
-	 * Passed into `JSON.stringify`.
-	 */
-	readonly replacer?: Replacer | Array<number | string>;
+	Stringify and write JSON to a file atomically.
+
+	Creates directories for you as needed.
+
+	@example
+	```
+	import writeJsonFile = require('write-json-file');
+
+	(async () => {
+		await writeJsonFile('foo.json', {foo: true});
+	})();
+	```
+	*/
+	(
+		filepath: string,
+		data: writeJsonFile.JSONStringifyable,
+		options?: writeJsonFile.Options
+	): Promise<void>;
 
 	/**
-	 * Mode used when writing the file.
-	 *
-	 * @default 0o666
-	 */
-	readonly mode?: number;
-}
+	Stringify and write JSON to a file atomically.
+
+	Creates directories for you as needed.
+
+	@example
+	```
+	import writeJsonFile = require('write-json-file');
+
+	writeJsonFile.sync('foo.json', {foo: true});
+	```
+	*/
+	sync(
+		filepath: string,
+		data: writeJsonFile.JSONStringifyable,
+		options?: writeJsonFile.Options
+	): void;
+
+	// TODO: Remove this for the next major release
+	default: typeof writeJsonFile;
+};
 
-/**
- * Stringify and write JSON to a file atomically.
- *
- * Creates directories for you as needed.
- *
- * @example
- *
- * import * as writeJsonFile from 'write-json-file';
- *
- * writeJsonFile.sync('foo.json', {foo: true});
- */
-export function sync(filepath: string, data: JSONStringifyable, options?: Options): void;
-
-/**
- * Stringify and write JSON to a file atomically.
- *
- * Creates directories for you as needed.
- *
- * @example
- *
- * import writeJsonFile from 'write-json-file';
- *
- * (async () => {
- * 	await writeJsonFile('foo.json', {foo: true});
- * })();
- */
-export default function writeJsonFile(filepath: string, data: JSONStringifyable, options?: Options): Promise<void>;
+export = writeJsonFile;
diff --git a/index.js b/index.js
index fb35f6f..12e637d 100644
--- a/index.js
+++ b/index.js
@@ -68,6 +68,7 @@ const writeJsonFile = (filePath, data, options) => {
 };
 
 module.exports = writeJsonFile;
+// TODO: Remove this for the next major release
 module.exports.default = writeJsonFile;
 module.exports.sync = (filePath, data, options) => {
 	makeDir.sync(path.dirname(filePath), {fs});
diff --git a/index.test-d.ts b/index.test-d.ts
index a7a22c0..71835cc 100644
--- a/index.test-d.ts
+++ b/index.test-d.ts
@@ -1,5 +1,6 @@
-import {expectType} from 'tsd-check';
-import writeJsonFile, {sync, Replacer, SortKeys, JSONStringifyable} from '.';
+import {expectType} from 'tsd';
+import writeJsonFile = require('.');
+import {sync, Replacer, SortKeys, JSONStringifyable} from '.';
 
 expectType<JSONStringifyable>('🦄');
 expectType<JSONStringifyable>(1);
@@ -23,18 +24,18 @@ expectType<Replacer>(() => () => 'foo');
 expectType<Replacer>((key: string) => key.toUpperCase());
 expectType<Replacer>((key: string, value: string) => (key + value).toUpperCase());
 
-expectType<void>(await writeJsonFile('unicorn.json', {unicorn: '🦄'}));
-expectType<void>(await writeJsonFile('unicorn.json', '🦄'));
-expectType<void>(await writeJsonFile('date.json', new Date()));
-expectType<void>(await writeJsonFile('unicorn.json', {unicorn: '🦄'}, {detectIndent: true}));
-expectType<void>(await writeJsonFile('unicorn.json', {unicorn: '🦄'}, {indent: ' '}));
-expectType<void>(await writeJsonFile('unicorn.json', {unicorn: '🦄'}, {indent: 4}));
-expectType<void>(await writeJsonFile('unicorn.json', {unicorn: '🦄'}, {mode: 0o666}));
-expectType<void>(await writeJsonFile('unicorn.json', {unicorn: '🦄'}, {replacer: ['unicorn', 1]}));
-expectType<void>(await writeJsonFile('unicorn.json', {unicorn: '🦄'}, {replacer: () => 'unicorn'}));
-expectType<void>(await writeJsonFile('unicorn.json', {unicorn: '🦄'}, {sortKeys: () => -1}));
-expectType<void>(await writeJsonFile('unicorn.json', {unicorn: '🦄'}, {sortKeys: (a: string, b: string) => a.length - b.length}));
-expectType<void>(await writeJsonFile('unicorn.json', {unicorn: '🦄'}, {sortKeys: true}));
+expectType<Promise<void>>(writeJsonFile('unicorn.json', {unicorn: '🦄'}));
+expectType<Promise<void>>(writeJsonFile('unicorn.json', '🦄'));
+expectType<Promise<void>>(writeJsonFile('date.json', new Date()));
+expectType<Promise<void>>(writeJsonFile('unicorn.json', {unicorn: '🦄'}, {detectIndent: true}));
+expectType<Promise<void>>(writeJsonFile('unicorn.json', {unicorn: '🦄'}, {indent: ' '}));
+expectType<Promise<void>>(writeJsonFile('unicorn.json', {unicorn: '🦄'}, {indent: 4}));
+expectType<Promise<void>>(writeJsonFile('unicorn.json', {unicorn: '🦄'}, {mode: 0o666}));
+expectType<Promise<void>>(writeJsonFile('unicorn.json', {unicorn: '🦄'}, {replacer: ['unicorn', 1]}));
+expectType<Promise<void>>(writeJsonFile('unicorn.json', {unicorn: '🦄'}, {replacer: () => 'unicorn'}));
+expectType<Promise<void>>(writeJsonFile('unicorn.json', {unicorn: '🦄'}, {sortKeys: () => -1}));
+expectType<Promise<void>>(writeJsonFile('unicorn.json', {unicorn: '🦄'}, {sortKeys: (a: string, b: string) => a.length - b.length}));
+expectType<Promise<void>>(writeJsonFile('unicorn.json', {unicorn: '🦄'}, {sortKeys: true}));
 
 expectType<void>(sync('unicorn.json', {unicorn: '🦄'}));
 expectType<void>(sync('unicorn.json', '🦄'));
diff --git a/package.json b/package.json
index 04c2bbe..8193020 100644
--- a/package.json
+++ b/package.json
@@ -13,7 +13,7 @@
 		"node": ">=6"
 	},
 	"scripts": {
-		"test": "xo && ava && tsd-check"
+		"test": "xo && ava && tsd"
 	},
 	"files": [
 		"index.js",
@@ -35,16 +35,16 @@
 	],
 	"dependencies": {
 		"detect-indent": "^5.0.0",
-		"graceful-fs": "^4.1.2",
-		"make-dir": "^1.0.0",
-		"pify": "^4.0.0",
+		"graceful-fs": "^4.1.15",
+		"make-dir": "^2.1.0",
+		"pify": "^4.0.1",
 		"sort-keys": "^2.0.0",
-		"write-file-atomic": "^2.0.0"
+		"write-file-atomic": "^2.4.2"
 	},
 	"devDependencies": {
-		"ava": "*",
+		"ava": "^1.4.1",
 		"tempfile": "^2.0.0",
-		"tsd-check": "^0.2.1",
-		"xo": "*"
+		"tsd": "^0.7.2",
+		"xo": "^0.24.0"
 	}
 }