diff --git a/package.json b/package.json
index 87dd14c..04b102c 100644
--- a/package.json
+++ b/package.json
@@ -15,7 +15,7 @@
   "scripts": {
     "test": "npm run test:unit && npm run test:typescript",
     "test:unit": "c8 --100 node --test",
-    "test:typescript": "tsd",
+    "test:typescript": "tstyche",
     "lint": "eslint",
     "lint:fix": "eslint --fix"
   },
@@ -29,7 +29,7 @@
     "fastify": "^5.0.0",
     "neostandard": "^0.13.0",
     "superagent": "^10.0.0",
-    "tsd": "^0.33.0"
+    "tstyche": "^7.0.0"
   },
   "homepage": "http://github.com/fastify/fastify-request-context",
   "funding": [
@@ -71,4 +71,4 @@
   "publishConfig": {
     "access": "public"
   }
-}
+}
\ No newline at end of file
diff --git a/tsconfig.json b/tsconfig.json
index 831e273..d67a670 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -1,14 +1,14 @@
 {
   "compilerOptions": {
     "outDir": "dist",
-    "module": "commonjs",
+    "rootDir": ".",
+    "module": "node16",
     "target": "es2022",
     "sourceMap": true,
     "declaration": true,
     "declarationMap": false,
-    "types": ["node"],
     "strict": true,
-    "moduleResolution": "node",
+    "moduleResolution": "node16",
     "noUnusedLocals": false,
     "noUnusedParameters": false,
     "noFallthroughCasesInSwitch": true,
@@ -20,7 +20,9 @@
     "allowSyntheticDefaultImports": true,
     "esModuleInterop": true,
     "forceConsistentCasingInFileNames": true,
-    "exactOptionalPropertyTypes": true
+    "exactOptionalPropertyTypes": true,
+    "types": ["node"]
   },
+  "include": ["types/**/*", "index.d.ts"],
   "exclude": ["node_modules", "test", "dist"]
 }
diff --git a/types/index.test-d.ts b/types/index.test-d.ts
deleted file mode 100644
index 2240d8a..0000000
--- a/types/index.test-d.ts
+++ /dev/null
@@ -1,84 +0,0 @@
-import {
-  requestContext,
-  asyncLocalStorage,
-  fastifyRequestContext,
-  FastifyRequestContextOptions,
-  RequestContext,
-  RequestContextDataFactory,
-} from '..'
-import { expectAssignable, expectType, expectError } from 'tsd'
-import { FastifyBaseLogger, FastifyInstance, RouteHandlerMethod } from 'fastify'
-import { AsyncLocalStorage } from 'node:async_hooks'
-
-const fastify = require('fastify')
-
-const app: FastifyInstance = fastify()
-app.register(fastifyRequestContext)
-
-declare module './index' {
-  interface RequestContextData {
-    a?: string
-    log?: FastifyBaseLogger
-  }
-}
-
-expectAssignable<FastifyRequestContextOptions>({})
-expectAssignable<FastifyRequestContextOptions>({
-  defaultStoreValues: { a: 'dummy' },
-})
-expectAssignable<FastifyRequestContextOptions>({
-  hook: 'preValidation',
-  defaultStoreValues: { a: 'dummy' },
-})
-expectAssignable<FastifyRequestContextOptions>({
-  defaultStoreValues: () => ({
-    a: 'dummy',
-  }),
-})
-
-expectError<FastifyRequestContextOptions>({
-  defaultStoreValues: { bar: 'dummy' },
-})
-
-expectError<FastifyRequestContextOptions>({
-  defaultStoreValues: { log: 'dummy' },
-})
-
-expectAssignable<RequestContextDataFactory>(() => ({
-  a: 'dummy',
-}))
-
-expectAssignable<FastifyRequestContextOptions>({
-  defaultStoreValues: (req) => ({
-    log: req.log.child({ childLog: true }),
-  }),
-})
-
-expectAssignable<RequestContextDataFactory>((req) => ({
-  log: req.log.child({ childLog: true }),
-}))
-
-expectError<RequestContextDataFactory>(() => ({ bar: 'dummy' }))
-expectError<RequestContextDataFactory>(() => ({ log: 'dummy' }))
-
-expectType<RequestContext>(app.requestContext)
-expectType<RequestContext>(requestContext)
-expectType<AsyncLocalStorage<RequestContext>>(asyncLocalStorage)
-
-const getHandler: RouteHandlerMethod = function (request, _reply) {
-  expectType<RequestContext>(request.requestContext)
-}
-expectType<RouteHandlerMethod>(getHandler)
-
-expectType<string | undefined>(requestContext.get('a'))
-expectType<FastifyBaseLogger | undefined>(requestContext.get('log'))
-
-expectError(requestContext.get('bar'))
-
-// Test exactOptionalPropertyTypes: true
-
-requestContext.set('a', undefined) // Should not error
-expectError(requestContext.set('a', 123))
-expectError<FastifyRequestContextOptions>({
-  defaultStoreValues: { a: undefined },
-})
diff --git a/types/index.tst.ts b/types/index.tst.ts
new file mode 100644
index 0000000..0a54d0e
--- /dev/null
+++ b/types/index.tst.ts
@@ -0,0 +1,88 @@
+import {
+  requestContext,
+  asyncLocalStorage,
+  fastifyRequestContext,
+  FastifyRequestContextOptions,
+  RequestContext,
+  RequestContextDataFactory,
+} from '..'
+import { expect } from 'tstyche'
+import { fastify, FastifyBaseLogger, FastifyInstance, RouteHandlerMethod, FastifyRequest } from 'fastify'
+import { AsyncLocalStorage } from 'node:async_hooks'
+
+const app: FastifyInstance = fastify()
+app.register(fastifyRequestContext)
+
+declare module '..' {
+  interface RequestContextData {
+    a?: string
+    log?: FastifyBaseLogger
+  }
+}
+
+expect<FastifyRequestContextOptions>().type.toBeAssignableFrom({})
+
+expect<FastifyRequestContextOptions>().type.toBeAssignableFrom({
+  defaultStoreValues: { a: 'dummy' },
+})
+
+expect<FastifyRequestContextOptions>().type.toBeAssignableFrom({
+  hook: 'preValidation' as const,
+  defaultStoreValues: { a: 'dummy' },
+})
+
+expect<FastifyRequestContextOptions>().type.toBeAssignableFrom({
+  defaultStoreValues: () => ({
+    a: 'dummy',
+  }),
+})
+
+expect<FastifyRequestContextOptions>().type.not.toBeAssignableFrom({
+  defaultStoreValues: { bar: 'dummy' },
+})
+
+expect<FastifyRequestContextOptions>().type.not.toBeAssignableFrom({
+  defaultStoreValues: { log: 'dummy' },
+})
+
+expect<RequestContextDataFactory>().type.toBeAssignableFrom(() => ({
+  a: 'dummy',
+}))
+
+expect<FastifyRequestContextOptions>().type.toBeAssignableFrom({
+  defaultStoreValues: (req: FastifyRequest) => ({
+    log: req.log.child({ childLog: true }),
+  }),
+})
+
+expect<RequestContextDataFactory>().type.toBeAssignableFrom((req: FastifyRequest) => ({
+  log: req.log.child({ childLog: true }),
+}))
+
+expect<RequestContextDataFactory>().type.not.toBeAssignableFrom(() => ({ bar: 'dummy' }))
+
+expect<RequestContextDataFactory>().type.not.toBeAssignableFrom(() => ({ log: 'dummy' }))
+
+expect(app.requestContext).type.toBe<RequestContext>()
+expect(requestContext).type.toBe<RequestContext>()
+expect(asyncLocalStorage).type.toBe<AsyncLocalStorage<RequestContext>>()
+
+const getHandler: RouteHandlerMethod = function (request, _reply) {
+  expect(request.requestContext).type.toBe<RequestContext>()
+}
+expect(getHandler).type.toBe<RouteHandlerMethod>()
+
+expect(requestContext.get('a')).type.toBe<string | undefined>()
+expect(requestContext.get('log')).type.toBe<FastifyBaseLogger | undefined>()
+
+// @ts-expect-error: Argument of type '"bar"' is not assignable
+requestContext.get('bar')
+
+requestContext.set('a', undefined)
+
+// @ts-expect-error: Argument of type 'number' is not assignable
+requestContext.set('a', 123)
+
+expect<FastifyRequestContextOptions>().type.not.toBeAssignableFrom({
+  defaultStoreValues: { a: undefined },
+})