diff --git a/src/examples/basic.ts b/src/examples/basic.ts
index cce01db..e7ddc41 100644
--- a/src/examples/basic.ts
+++ b/src/examples/basic.ts
@@ -41,7 +41,7 @@ to Express.js
 api.use(toJson)
 api.use(hydrateDates)
 
-function sampleMiddleware(data: ApiResponse) {
+async function sampleMiddleware(data: ApiResponse) {
   return data
 }
 
diff --git a/src/lib/auth.service.ts b/src/lib/auth.service.ts
index 81be33f..a49e5a4 100644
--- a/src/lib/auth.service.ts
+++ b/src/lib/auth.service.ts
@@ -12,7 +12,7 @@ class OzzzyAuth implements AuthProvider {
     this.header = header
   }
 
-  getHeaders(): Array<Array<string>> {
+  getHeaders(): [string, string][] {
     switch (this.type) {
       case AuthTypes.Bearer:
         return [[this.header!, `${this.type} ${this.token}`]]
diff --git a/src/lib/http-api.service.ts b/src/lib/http-api.service.ts
index 2b3517f..ad657fc 100644
--- a/src/lib/http-api.service.ts
+++ b/src/lib/http-api.service.ts
@@ -68,10 +68,7 @@ export class HttpApi {
    * @returns The response, after all middleware has been applied
    * @example await api.get('/users/all')
    */
-  get<K = unknown>(
-    url: URL,
-    ...middleware: Middleware<K, unknown>[]
-  ): Promise<K> {
+  get<K = unknown>(url: URL, ...middleware: Middleware[]): Promise<K> {
     const requestMiddleware = [...this.middleware, ...middleware]
     const options = { method: RestMethods.GET }
     return this._fetch<K>(url, options, requestMiddleware)
@@ -88,7 +85,7 @@ export class HttpApi {
   put<K = unknown>(
     url: URL,
     payload: object,
-    ...middleware: Middleware<K, unknown>[]
+    ...middleware: Middleware[]
   ): Promise<K> {
     const requestMiddleware = [...this.middleware, ...middleware]
     const options = {
@@ -109,7 +106,7 @@ export class HttpApi {
   post<K = unknown>(
     url: URL,
     payload: object,
-    ...middleware: Middleware<K, unknown>[]
+    ...middleware: Middleware[]
   ): Promise<K> {
     const requestMiddleware = [...this.middleware, ...middleware]
     const options = {
@@ -130,7 +127,7 @@ export class HttpApi {
   delete<K = unknown>(
     url: URL,
     payload: object,
-    ...middleware: Middleware<K, unknown>[]
+    ...middleware: Middleware[]
   ): Promise<K> {
     const requestMiddleware = [...this.middleware, ...middleware]
     const options = {
@@ -171,7 +168,7 @@ export class HttpApi {
   private async _fetch<K>(
     url: URL,
     options: object,
-    middleware: Middleware<K, unknown>[],
+    middleware: Middleware[],
   ): Promise<K> {
     let combinedHeaders = [...this.headers]
     if (this.auth !== undefined) {
diff --git a/src/middleware/dates.middleware.ts b/src/middleware/dates.middleware.ts
index 451ed8c..e83b0a9 100644
--- a/src/middleware/dates.middleware.ts
+++ b/src/middleware/dates.middleware.ts
@@ -15,7 +15,7 @@ const dateFormat = /^-?\d+-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}\.\d{3}Z$/
  * If there is a match, it returns the value as a date,
  * if not, it returns the value as is
  */
-function dateReviver(_key: string, value: any) {
+function dateReviver(_key: string, value: unknown) {
   if (typeof value === 'string' && dateFormat.test(value)) {
     return new Date(value)
   }
@@ -29,7 +29,7 @@ function dateReviver(_key: string, value: any) {
  * Note that this data is expected to be a Javascript object
  * @returns Hydrated data object
  */
-export function hydrateDates(data: object): Promise<any> {
+export function hydrateDates(data: object): Promise<object> {
   const dataAsString = JSON.stringify(data)
   const hydratedData = JSON.parse(dataAsString, dateReviver)
 
diff --git a/src/middleware/json.middleware.ts b/src/middleware/json.middleware.ts
index 9ce1792..3d7379a 100644
--- a/src/middleware/json.middleware.ts
+++ b/src/middleware/json.middleware.ts
@@ -6,6 +6,6 @@
  * @param next Next middleware handler function
  * @returns Call to next middleware handler
  */
-export function toJson(response: Response): Promise<any> {
+export function toJson(response: Response): Promise<object> {
   return response.json()
 }
diff --git a/src/shared-types/middleware.type.ts b/src/shared-types/middleware.type.ts
index e6506ab..0dbc37e 100644
--- a/src/shared-types/middleware.type.ts
+++ b/src/shared-types/middleware.type.ts
@@ -1 +1,2 @@
-export type Middleware<K = unknown, V = unknown> = (data: K) => Promise<V>
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+export type Middleware<K = any, V = any> = (data: K) => Promise<V>