diff --git a/.eslintrc.cjs b/.eslintrc.cjs
index 58e7202..47919d5 100644
--- a/.eslintrc.cjs
+++ b/.eslintrc.cjs
@@ -4,6 +4,7 @@ module.exports = {
   extends: [
     'eslint:recommended',
     'plugin:@typescript-eslint/recommended',
+    'plugin:@typescript-eslint/stylistic-type-checked',
     'prettier',
   ],
   overrides: [
@@ -25,6 +26,7 @@ module.exports = {
           'error',
           { allow: ['/package\\.json$'] },
         ],
+        '@typescript-eslint/array-type': ['error', { default: 'generic' }],
       },
     },
     // Tests
diff --git a/src/__tests__/package-json-file-service.test.ts b/src/__tests__/package-json-file-service.test.ts
index 7981cfe..d9c963e 100644
--- a/src/__tests__/package-json-file-service.test.ts
+++ b/src/__tests__/package-json-file-service.test.ts
@@ -91,6 +91,8 @@ async function _writeFixture(withTrailingNewline = false): Promise<string> {
   return file
 }
 
-function cleanup(...files: string[]): Promise<any> {
-  return Promise.all(files.map((f) => fsp.unlink(f)))
+async function cleanup(...files: Array<string>): Promise<void> {
+  await Promise.all(files.map((f) => fsp.unlink(f)))
+
+  return
 }
diff --git a/src/__tests__/type-syncer.test.ts b/src/__tests__/type-syncer.test.ts
index 7ef1712..3c724b1 100644
--- a/src/__tests__/type-syncer.test.ts
+++ b/src/__tests__/type-syncer.test.ts
@@ -13,7 +13,7 @@ import type {
   IWorkspaceResolverService,
 } from '../workspace-resolver'
 
-const descriptors: IPackageTypingDescriptor[] = [
+const descriptors: Array<IPackageTypingDescriptor> = [
   {
     typingsName: 'package1',
     codePackageName: 'package1',
diff --git a/src/__tests__/versioning.test.ts b/src/__tests__/versioning.test.ts
index 116363d..237c84b 100644
--- a/src/__tests__/versioning.test.ts
+++ b/src/__tests__/versioning.test.ts
@@ -5,7 +5,7 @@ import {
 
 describe('getClosestMatchingVersion', () => {
   it('returns the closest matching version', () => {
-    const inputVersions: IPackageVersionInfo[] = [
+    const inputVersions: Array<IPackageVersionInfo> = [
       {
         containsInternalTypings: false,
         version: '1.16.0',
diff --git a/src/cli.ts b/src/cli.ts
index be4876f..91c3857 100644
--- a/src/cli.ts
+++ b/src/cli.ts
@@ -33,8 +33,8 @@ export async function startCli() {
       typeSyncer: asFunction(createTypeSyncer),
     })
     await run(container.resolve<ITypeSyncer>('typeSyncer'))
-  } catch (err: any) {
-    C.error(err)
+  } catch (err) {
+    C.error(err as any)
     process.exitCode = 1
   }
 }
@@ -109,7 +109,7 @@ function renderSyncedFile(file: ISyncedFile) {
       : chalk`{green.bold (${file.newTypings.length.toString()} new typings added)}`
 
   const dirName = path.basename(path.dirname(path.resolve(file.filePath)))
-  const title = chalk`📦 ${file.package.name || dirName} {gray.italic — ${
+  const title = chalk`📦 ${file.package.name ?? dirName} {gray.italic — ${
     file.filePath
   }} ${badge}`
 
diff --git a/src/config-service.ts b/src/config-service.ts
index 714bb55..87dc36c 100644
--- a/src/config-service.ts
+++ b/src/config-service.ts
@@ -40,7 +40,7 @@ function readCliConfig(flags: ICLIArguments['flags']): ISyncOptions {
   const readValues = <T extends string>(
     key: string,
     validator?: (value: string) => boolean,
-  ): T[] | undefined => {
+  ): Array<T> | undefined => {
     const values = flags[key]
     return typeof values === 'string'
       ? values
diff --git a/src/fs-utils.ts b/src/fs-utils.ts
index 4dc666e..8dbda87 100644
--- a/src/fs-utils.ts
+++ b/src/fs-utils.ts
@@ -12,14 +12,15 @@ async function assertFile(filePath: string) {
 }
 
 async function existsAsync(filePath: string): Promise<boolean> {
-  return stat(filePath)
-    .then(() => true)
-    .catch((err) => {
-      /* istanbul ignore else */
-      if (err.code === 'ENOENT') {
-        return false
-      }
-      /* istanbul ignore next */
-      throw err
-    })
+  try {
+    await stat(filePath)
+    return true
+  } catch (err) {
+    /* istanbul ignore else */
+    if ((err as { code: string }).code === 'ENOENT') {
+      return false
+    }
+    /* istanbul ignore next */
+    throw err
+  }
 }
diff --git a/src/package-json-file-service.ts b/src/package-json-file-service.ts
index 927e3ee..41a49f8 100644
--- a/src/package-json-file-service.ts
+++ b/src/package-json-file-service.ts
@@ -26,9 +26,7 @@ export function createPackageJSONFileService(): IPackageJSONService {
     writePackageFile: async (filePath, fileContent) => {
       const contents = await readFileContents(filePath)
       const { indent } = detectIndent(contents)
-      const trailingNewline = contents.length
-        ? contents[contents.length - 1] === '\n'
-        : false
+      const trailingNewline = contents.length ? contents.endsWith('\n') : false
       const data = JSON.stringify(
         fileContent,
         null,
diff --git a/src/package-source.ts b/src/package-source.ts
index 9f8b88a..342eb7a 100644
--- a/src/package-source.ts
+++ b/src/package-source.ts
@@ -11,7 +11,7 @@ export interface IPackageSource {
    *
    * @param packageName
    */
-  fetch(packageName: string): Promise<IPackageInfo | null>
+  fetch(this: void, packageName: string): Promise<IPackageInfo | null>
 }
 
 /**
@@ -33,7 +33,7 @@ export function createPackageSource(): IPackageSource {
      * Fetches info about a package, or `null` if not found.
      */
     fetch: async (name) => {
-      const response = await fetch(encodeURI(name)).catch((err: any) => {
+      const response = await fetch(encodeURI(name)).catch((err) => {
         if (err.statusCode === 404) {
           return null
         }
diff --git a/src/type-syncer.ts b/src/type-syncer.ts
index 770f68f..561fa0c 100644
--- a/src/type-syncer.ts
+++ b/src/type-syncer.ts
@@ -86,7 +86,7 @@ export function createTypeSyncer(
     const { ignoreDeps, ignorePackages } = opts
 
     const packageFile =
-      file || (await packageJSONService.readPackageFile(filePath))
+      file ?? (await packageJSONService.readPackageFile(filePath))
     const allLocalPackages = Object.values(IDependencySection)
       .map((dep) => {
         const section = getDependenciesBySection(packageFile, dep)
@@ -241,14 +241,15 @@ function getPackageScope(packageName: string): [string, string] | null {
 function getPackagesFromSection(
   section: IDependenciesSection,
   ignoredSection?: boolean,
-  ignorePackages?: string[],
-): IPackageVersion[] {
+  ignorePackages?: Array<string>,
+): Array<IPackageVersion> {
   return filterMap(Object.keys(section), (name) => {
     const isTyping = name.startsWith('@types/')
 
     // Never ignore `@types` packages.
     if (!isTyping) {
       // If it's not a `@types` package, check whether the section or package is ignored.
+      // eslint-disable-next-line @typescript-eslint/prefer-nullish-coalescing -- We want to check for false as well.
       if (ignoredSection || ignorePackages?.includes(name)) {
         return false
       }
diff --git a/src/types.ts b/src/types.ts
index 96b3c7b..30324f4 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -14,11 +14,11 @@ export interface ISyncOptions {
   /**
    * Ignore certain deps.
    */
-  ignoreDeps?: IDependencySection[]
+  ignoreDeps?: Array<IDependencySection>
   /**
    * Ignore certain packages.
    */
-  ignorePackages?: string[]
+  ignorePackages?: Array<string>
 }
 
 /**
@@ -37,9 +37,7 @@ export interface IPackageFile {
 /**
  * Section in package.json representing dependencies.
  */
-export interface IDependenciesSection {
-  [packageName: string]: string
-}
+export type IDependenciesSection = Record<string, string>
 
 /**
  * Package + version record, collected from the {"package": "^1.2.3"} sections.
@@ -107,6 +105,6 @@ export enum IDependencySection {
  * CLI arguments.
  */
 export interface ICLIArguments {
-  flags: { [key: string]: boolean | string | undefined }
+  flags: Record<string, boolean | string | undefined>
   args: Array<string>
 }
diff --git a/src/util.ts b/src/util.ts
index 2ab304b..e9b5d82 100644
--- a/src/util.ts
+++ b/src/util.ts
@@ -53,7 +53,7 @@ export function shrinkObject<T extends object>(source: T): Required<T> {
  * @param source An array of objects to merge.
  */
 export function mergeObjects<T>(source: Array<T>): T {
-  return source.reduce((accum: any, next: any) => ({ ...accum, ...next }), {})
+  return source.reduce((accum, next) => ({ ...accum, ...next }), {} as T)
 }
 
 /**
@@ -91,13 +91,14 @@ export function untyped(name: string): string {
  * Orders an object.
  * @param source
  */
-export function orderObject<
-  T extends Record<string | number | symbol, unknown>,
->(source: T, comparer?: (a: string, b: string) => number): T {
+export function orderObject<T extends Record<string | number | symbol, U>, U>(
+  source: T,
+  comparer?: (a: string, b: string) => number,
+): T {
   const keys = Object.keys(source).sort(comparer)
-  const result: any = {}
+  const result: Record<string, U> = {}
   for (const key of keys) {
-    result[key] = (source as any)[key]
+    result[key] = source[key]
   }
 
   return result as T
@@ -108,10 +109,10 @@ export function orderObject<
  *
  * @param fn
  */
-export function memoizeAsync<U extends any[], V>(
+export function memoizeAsync<U extends Array<W>, V, W>(
   fn: (...args: U) => Promise<V>,
 ) {
-  const cache = new Map<any, Promise<V>>()
+  const cache = new Map<W, Promise<V>>()
 
   async function run(...args: U): Promise<V> {
     try {
diff --git a/src/versioning.ts b/src/versioning.ts
index e1fc3c4..8ff523e 100644
--- a/src/versioning.ts
+++ b/src/versioning.ts
@@ -15,7 +15,7 @@ export interface IPackageVersionInfo {
  * @param version
  */
 export function getClosestMatchingVersion(
-  availableVersions: IPackageVersionInfo[],
+  availableVersions: Array<IPackageVersionInfo>,
   version: string,
 ) {
   const parsedVersion = parseVersion(version)
@@ -40,7 +40,7 @@ export function getClosestMatchingVersion(
     return true
   })
 
-  return bestMatch || availableVersions[0]
+  return bestMatch ?? availableVersions[0]
 }
 
 /**
diff --git a/src/workspace-resolver.ts b/src/workspace-resolver.ts
index 31da5a8..ab0cd6e 100644
--- a/src/workspace-resolver.ts
+++ b/src/workspace-resolver.ts
@@ -37,7 +37,7 @@ export type IWorkspacesArray = Array<string>
  * - 'packages/*'
  * ```
  */
-export type IWorkspacesObject = {
+export interface IWorkspacesObject {
   packages: IWorkspacesArray
 }
 
@@ -61,7 +61,7 @@ type NpmWorkspacesConfig = IWorkspacesArray
  */
 type YarnWorkspacesConfig =
   | IWorkspacesArray
-  | (IWorkspacesObject & { nohoist?: string[] })
+  | (IWorkspacesObject & { nohoist?: Array<string> })
 
 /**
  * The contents of a `pnpm-workspace.yaml` file.