diff --git a/build.gradle b/build.gradle
index b1c4425..0da2ee0 100644
--- a/build.gradle
+++ b/build.gradle
@@ -12,7 +12,6 @@ buildscript {
     dependencies {
         classpath deps.plugins.kotlin
         classpath deps.plugins.dokka
-        classpath deps.plugins.node
     }
 }
 apply from: "$rootDir/gradle/dependencies.gradle"
@@ -22,6 +21,7 @@ allprojects {
         google()
         jcenter()
         maven { url "https://oss.sonatype.org/content/repositories/snapshots" }
+        maven { url "https://dl.bintray.com/spekframework/spek-dev" }
 
     }
 
diff --git a/gradle/dependencies.gradle b/gradle/dependencies.gradle
index 499409b..c3d81f6 100644
--- a/gradle/dependencies.gradle
+++ b/gradle/dependencies.gradle
@@ -1,12 +1,13 @@
 ext.versions = [
         kotlin          : '1.3.30',
         dokka           : '0.9.17',
+        spek            : '2.1.0-alpha.0.9+3d5d865',
+        atrium          : '0.8.0'
 ]
+
 ext.deps = [
         plugins: [
-                android: 'com.android.tools.build:gradle:3.3.0',
                 kotlin : "org.jetbrains.kotlin:kotlin-gradle-plugin:${versions.kotlin}",
                 dokka  : "org.jetbrains.dokka:dokka-gradle-plugin:${versions.dokka}",
-                node   : "com.moowork.gradle:gradle-node-plugin:${versions.nodePlugin}"
         ]
 ]
diff --git a/lib/build.gradle b/lib/build.gradle
index fe31107..e13d63d 100644
--- a/lib/build.gradle
+++ b/lib/build.gradle
@@ -1,3 +1,6 @@
+repositories {
+    maven { url "https://dl.bintray.com/spekframework/spek-dev" }
+}
 apply plugin: 'java'
 apply plugin: 'kotlin-multiplatform'
 
@@ -35,10 +38,13 @@ kotlin {
             }
         }
         commonTest {
-            kotlin.srcDir('src/test')
+            kotlin.srcDir('src/test/kotlin')
             dependencies {
                 implementation kotlin("test-common")
                 implementation kotlin("test-annotations-common")
+                implementation "org.spekframework.spek2:spek-dsl-metadata:$project.versions.spek"
+                implementation "ch.tutteli.atrium:atrium-cc-en_GB-robstoll-common:$project.versions.atrium"
+                implementation "io.mockk:mockk-common:1.9.3"
             }
         }
 
@@ -52,7 +58,12 @@ kotlin {
             dependencies {
                 implementation kotlin("test")
                 implementation kotlin("test-junit")
-                implementation 'junit:junit:4.12'
+                implementation "org.spekframework.spek2:spek-dsl-jvm:$project.versions.spek"
+                implementation "ch.tutteli.atrium:atrium-cc-en_GB-robstoll:$project.versions.atrium"
+                implementation "io.mockk:mockk:1.9.3"
+
+                runtimeOnly "org.spekframework.spek2:spek-runner-junit5:$project.versions.spek"
+                runtimeOnly 'org.jetbrains.kotlin:kotlin-reflect'
             }
         }
         jsMain {
@@ -118,3 +129,8 @@ publishing {
     }
 }
 
+jvmTest {
+    useJUnitPlatform {
+        includeEngines 'spek2'
+    }
+}
diff --git a/lib/src/commonMain/kotlin/org/reduxkotlin/ApplyMiddleware.kt b/lib/src/commonMain/kotlin/org/reduxkotlin/ApplyMiddleware.kt
index 7c1a170..432b4a9 100644
--- a/lib/src/commonMain/kotlin/org/reduxkotlin/ApplyMiddleware.kt
+++ b/lib/src/commonMain/kotlin/org/reduxkotlin/ApplyMiddleware.kt
@@ -16,23 +16,21 @@ package org.reduxkotlin
  * @param {vararg Middleware} [middleware] The middleware chain to be applied.
  * @returns {StoreEnhancer} A store enhancer applying the middleware.
  */
-fun <S : Any> applyMiddleware(vararg middlewares: Middleware<S>): StoreEnhancer<S> {
+fun applyMiddleware(vararg middlewares: Middleware): StoreEnhancer {
     return { storeCreator ->
-        { reducer, initialState ->
-            val store = storeCreator(reducer, initialState)
-            //TODO determine if handling dispatching while constructing middleware is needed.
-            //reduxjs throws an exception if action is dispatched before applymiddleware is complete
-            /*
+        { reducer, initialState, en ->
+            val store = storeCreator(reducer, initialState, en)
             var dispatch: Dispatcher = { action: Any ->
                 throw Exception(
                         """Dispatching while constructing your middleware is not allowed.
                     Other middleware would not be applied to this dispatch.""")
             }
-             */
+            store.dispatch = dispatch
+            val chain = middlewares.map { middleware -> middleware(store) }
+            dispatch = compose(chain)(store.dispatch)
 
-            val combinedDispatch = middlewares.foldRight(store.dispatch) { middleware, next -> {action -> middleware(store.getState, next, action)}}
             Store(getState = store.getState,
-                    dispatch = combinedDispatch,
+                    dispatch = dispatch,
                     subscribe = store.subscribe,
                     replaceReducer = store.replaceReducer)
         }
diff --git a/lib/src/commonMain/kotlin/org/reduxkotlin/CreateStore.kt b/lib/src/commonMain/kotlin/org/reduxkotlin/CreateStore.kt
index b92550b..516e9f9 100644
--- a/lib/src/commonMain/kotlin/org/reduxkotlin/CreateStore.kt
+++ b/lib/src/commonMain/kotlin/org/reduxkotlin/CreateStore.kt
@@ -25,11 +25,11 @@ import org.reduxkotlin.utils.isPlainObject
  * @returns {Store} A Redux store that lets you read the state, dispatch actions
  * and subscribe to changes.
  */
-fun <S> createStore(reducer: Reducer<S>, preloadedState: S, enhancer: StoreEnhancer<S>? = null): Store<S> {
+fun createStore(reducer: Reducer, preloadedState: Any, enhancer: StoreEnhancer? = null): Store {
 
 
     if (enhancer != null) {
-        return enhancer { reducer, initialState -> createStore(reducer, initialState) }(reducer, preloadedState)
+        return enhancer { reducer, initialState, en -> createStore(reducer, initialState) }(reducer, preloadedState, null)
     }
 
 
@@ -57,7 +57,7 @@ fun <S> createStore(reducer: Reducer<S>, preloadedState: S, enhancer: StoreEnhan
      *
      * @returns {S} The current state tree of your application.
      */
-    fun getState(): S {
+    fun getState(): Any {
         if (isDispatching) {
             throw Exception(
                     """You may not call store.getState() while the reducer is executing.
@@ -184,7 +184,7 @@ fun <S> createStore(reducer: Reducer<S>, preloadedState: S, enhancer: StoreEnhan
      * @param {function} nextReducer The reducer for the store to use instead.
      * @returns {void}
      */
-    fun replaceReducer(nextReducer: Reducer<S>) {
+    fun replaceReducer(nextReducer: Reducer) {
         currentReducer = nextReducer
 
         // This action has a similar effect to ActionTypes.INIT.
diff --git a/lib/src/commonMain/kotlin/org/reduxkotlin/Definitions.kt b/lib/src/commonMain/kotlin/org/reduxkotlin/Definitions.kt
index 0e4ce81..07dd6b6 100644
--- a/lib/src/commonMain/kotlin/org/reduxkotlin/Definitions.kt
+++ b/lib/src/commonMain/kotlin/org/reduxkotlin/Definitions.kt
@@ -1,30 +1,79 @@
 package org.reduxkotlin
 
+import kotlin.reflect.KClass
+
 /**
  * see also https://github.com/reactjs/redux/blob/master/docs/Glossary.md#reducer
  */
-typealias Reducer<ReducerStateType> = (state: ReducerStateType, action: Any) -> ReducerStateType
-typealias GetState<S> = () -> S
-typealias StoreSubscriber = ()-> Unit
+typealias Reducer = (state: Any, action: Any) -> Any
+
+typealias GetState = () -> Any
+typealias StoreSubscriber = () -> Unit
 typealias StoreSubscription = () -> Unit
-typealias Dispatcher = (Any)->Any
-typealias StoreCreator<S> = (reducer: Reducer<S>, initialState: S) -> Store<S>
+typealias Dispatcher = (Any) -> Any
+typealias StoreCreator = (reducer: Reducer, initialState: Any, s: StoreEnhancerWrapper?) -> Store
 /**
  * get a store creator and return a new enhanced one
  * see https://github.com/reactjs/redux/blob/master/docs/Glossary.md#store-enhancer
  */
-typealias StoreEnhancer<S> = (next: StoreCreator<S>) -> StoreCreator<S>
+typealias StoreEnhancer = (next: StoreCreator) -> StoreCreator
+
+/**
+ * wrapper class is needed here to avoid a recursive type declaration.
+ */
+class StoreEnhancerWrapper(val storeEnhancer2: StoreEnhancer) : StoreEnhancer {
+    override fun invoke(p1: StoreCreator): StoreCreator {
+        return storeEnhancer2(p1)
+    }
+}
 
 /**
  * see also https://github.com/reactjs/redux/blob/master/docs/Glossary.md#middleware
  */
-typealias Middleware<State> = (getState: GetState<State>, nextDispatcher: Dispatcher, action: Any) -> Any
+typealias Middleware = (store: Store) -> (next: Dispatcher) -> (action: Any) -> Any
 
 
-data class Store<S>(val getState: GetState<S>,
-                    var dispatch: Dispatcher,
-                    val subscribe: (StoreSubscriber) -> StoreSubscription,
-                    val replaceReducer: (Reducer<S>) -> Unit) {
-    val state: S
+data class Store(
+    val getState: GetState,
+    var dispatch: Dispatcher,
+    val subscribe: (StoreSubscriber) -> StoreSubscription,
+    val replaceReducer: (Reducer) -> Unit
+) {
+    val state: Any
         get() = getState()
 }
+
+/**
+ * Convenience function for creating a middleware
+ * usage:
+ *    val myMiddleware = middleware { store, dispatch, action -> doStuff() }
+ */
+fun middleware(dispatch: (Store, dispatch: Dispatcher, action: Any) -> Any): Middleware =
+    { store ->
+        { next ->
+            { action: Any ->
+                {
+                    dispatch(store, next, action)
+                }
+            }
+        }
+    }
+
+/**
+ * Creates a function that returns reducers with state casted to given state.
+ * This is to assist in readability of creating reducers and remove the need to cast.
+ * usage:
+ *   * create reducers with castingReducer:
+ *      val reducer = castingReducer { state: MyState, action ->
+ *              when (action) {
+ *                  is Todo -> state.copy(...)
+ *              }
+ *          }
+ */
+inline fun <reified T> castingReducer(crossinline reducer: ((T, Any) -> Any)): Reducer = { state: Any, action: Any ->
+    if (T::class.isInstance(state)) {
+        reducer(state as T, action)
+    } else {
+        { state: Any, action: Any -> state }
+    }
+}
diff --git a/lib/src/commonMain/kotlin/org/reduxkotlin/combineEnhancers.kt b/lib/src/commonMain/kotlin/org/reduxkotlin/combineEnhancers.kt
index 2d1049d..abf4b50 100644
--- a/lib/src/commonMain/kotlin/org/reduxkotlin/combineEnhancers.kt
+++ b/lib/src/commonMain/kotlin/org/reduxkotlin/combineEnhancers.kt
@@ -1,7 +1,7 @@
 package org.reduxkotlin
 
 
-fun <S> combineEnhancers(vararg enhancers: StoreEnhancer<S>): StoreEnhancer<S> =
+fun combineEnhancers(vararg enhancers: StoreEnhancer): StoreEnhancer =
         { storeCreator ->
             compose(enhancers.map { it })(storeCreator)
         }
diff --git a/lib/src/commonMain/kotlin/org/reduxkotlin/combineReducers.kt b/lib/src/commonMain/kotlin/org/reduxkotlin/combineReducers.kt
index ae2ab08..98e7da7 100644
--- a/lib/src/commonMain/kotlin/org/reduxkotlin/combineReducers.kt
+++ b/lib/src/commonMain/kotlin/org/reduxkotlin/combineReducers.kt
@@ -1,11 +1,11 @@
 package org.reduxkotlin
 
-fun <S> combineReducers(vararg reducers: Reducer<S>): Reducer<S> =
+fun <S> combineReducers(vararg reducers: Reducer): Reducer =
         { state, action ->
             reducers.fold(state, { s, reducer -> reducer(s, action) })
         }
 
-fun <S> Reducer<S>.combinedWith(vararg reducers: Reducer<S>): Reducer<S> {
+fun <S> Reducer.combinedWith(vararg reducers: Reducer): Reducer {
     return { state, action ->
         val sAfterFirstReducer = this(state, action)
         reducers.fold(sAfterFirstReducer, { s, reducer -> reducer(s, action) })
@@ -15,6 +15,6 @@ fun <S> Reducer<S>.combinedWith(vararg reducers: Reducer<S>): Reducer<S> {
 /**
  * combine two reducer with + operator
  */
-operator fun <S> Reducer<S>.plus(other: Reducer<S>): Reducer<S> = { s, a ->
+operator fun <S> Reducer.plus(other: Reducer): Reducer = { s, a ->
     other(this(s, a), a)
 }
\ No newline at end of file
diff --git a/lib/src/test/kotlin/org/reduxkotlin/ApplyMiddlewareTest.kt b/lib/src/test/kotlin/org/reduxkotlin/ApplyMiddlewareTest.kt
new file mode 100644
index 0000000..10636ca
--- /dev/null
+++ b/lib/src/test/kotlin/org/reduxkotlin/ApplyMiddlewareTest.kt
@@ -0,0 +1,91 @@
+package org.reduxkotlin
+
+import ch.tutteli.atrium.api.cc.en_GB.toBe
+import ch.tutteli.atrium.api.cc.en_GB.toThrow
+import ch.tutteli.atrium.verbs.expect
+import io.mockk.spyk
+import org.spekframework.spek2.Spek
+import org.spekframework.spek2.style.specification.describe
+import kotlin.test.assertEquals
+
+
+object ApplyMiddlewareSpec : Spek({
+    describe("middleware") {
+        it("fails") {
+            spyk(Any())
+            expect(1).toBe(1)
+            assertEquals(1, 1)
+        }
+    }
+
+    describe("applyMiddleware") {
+        it("warns when dispatching during middleware setup") {
+            fun dispatchingMiddleware(store: Store): (next: Dispatcher) -> (action: Any) -> Any {
+                store.dispatch(AddTodo("1", "Dont dispatch in middleware setup"));
+                return { next ->
+                    { action ->
+                        {
+                            next(action)
+                        }
+                    }
+                }
+            }
+
+            expect {
+                val storeEnhancer = applyMiddleware(::dispatchingMiddleware)
+                storeEnhancer(::createStore)(todos, Any(), null)
+            }.toThrow<Exception> {}
+        }
+
+        /*
+        it("wraps dispatch method with middleware once") {
+            fun test(spyOnMethods) {
+                return methods => {
+                    spyOnMethods(methods)
+                    return next => action => next(action)
+                }
+            }
+
+            val spy = jest.fn()
+            val store = applyMiddleware (test(spy), thunk)(createStore)(reducers.todos)
+
+            store.dispatch(AddTodo("Use Redux"))
+            store.dispatch(AddTodo("Flux FTW!"))
+
+            expect(spy.mock.calls.length).toBe(1)
+
+            expect(spy.mock.calls[0][0]).toHaveProperty("getState")
+            expect(spy.mock.calls[0][0]).toHaveProperty("dispatch")
+
+            expect(store.getState()).toEqual([
+                { id: 1, text: "Use Redux" },
+                { id: 2, text: "Flux FTW!" }
+            ])
+        })
+
+         */
+
+    }
+})
+
+/************** Test Reducer & actions - tobe moved into example app *********/
+
+data class AddTodo(val id: String, val text: String)
+data class ToggleTodo(val id: String)
+data class Todo(val id: String, val text: String, val completed: Boolean = false)
+
+data class TestState(val todos: List<Todo> = listOf())
+
+val todos = castingReducer { state: TestState, action ->
+        when (action) {
+            is AddTodo -> state.copy(todos = state.todos.plus(Todo(action.id, action.text, false)))
+            is ToggleTodo -> state.copy(todos = state.todos.map {
+                if (it.id == action.id) {
+                    it.copy(completed = !it.completed)
+                } else {
+                    it
+                }
+            })
+            else -> state
+        }
+    }
\ No newline at end of file
diff --git a/lib/src/test/kotlin/org/reduxkotlin/CreateStoreSpec.kt b/lib/src/test/kotlin/org/reduxkotlin/CreateStoreSpec.kt
new file mode 100644
index 0000000..98217d7
--- /dev/null
+++ b/lib/src/test/kotlin/org/reduxkotlin/CreateStoreSpec.kt
@@ -0,0 +1,122 @@
+package org.reduxkotlin
+
+import ch.tutteli.atrium.api.cc.en_GB.toBe
+import ch.tutteli.atrium.verbs.expect
+import org.spekframework.spek2.Spek
+import org.spekframework.spek2.style.specification.describe
+
+object CreateStoreSpec : Spek({
+    describe("createStore") {
+        it("passes the initial state") {
+            val store = createStore(
+                todos, TestState(
+                    listOf(
+                        Todo(
+                            id = "1",
+                            text = "Hello"
+                        )
+                    )
+                )
+            )
+
+            expect(store.getState()).toBe(
+                TestState(
+                    listOf(
+                        Todo(
+                            id = "1",
+                            text = "Hello"
+                        )
+                    )
+                )
+            )
+        }
+        it("applies the reducer to the previous state") {
+            val store = createStore(todos, TestState())
+            expect(store.getState()).toBe(TestState())
+
+            store.dispatch(Any())
+            expect(store.getState()).toBe(TestState())
+
+            store.dispatch(AddTodo("1", "Hello"))
+            expect(store.getState()).toBe(
+                TestState(
+                    listOf(
+                        Todo(
+                            id = "1",
+                            text = "Hello"
+                        )
+                    )
+                )
+            )
+
+            //TODO are ids autoincrement?
+            store.dispatch(AddTodo("2", "World"))
+            expect(store.getState()).toBe(
+                TestState(
+                    listOf(
+                        Todo(
+                            id = "1",
+                            text = "Hello"
+                        ),
+                        Todo(
+                            id = "2",
+                            text = "World"
+                        )
+                    )
+                )
+            )
+        }
+
+        it("applies the reducer to the initial state") {
+            val store = createStore(
+                todos, TestState(
+                    listOf(
+                        Todo(
+                            id = "1",
+                            text = "Hello"
+                        )
+                    )
+                )
+            )
+            expect(store.getState()).toBe(
+                TestState(
+                    listOf(
+                        Todo(
+                            id = "1",
+                            text = "Hello"
+                        )
+                    )
+                )
+            )
+
+            store.dispatch(Any())
+            expect(store.getState()).toBe(
+                TestState(
+                    listOf(
+                        Todo(
+                            id = "1",
+                            text = "Hello"
+                        )
+                    )
+                )
+            )
+
+            store.dispatch(AddTodo("2", "World"))
+            expect(store.getState()).toBe(
+                TestState(
+                    listOf(
+                        Todo(
+                            id = "1",
+                            text = "Hello"
+                        ),
+                        Todo(
+                            id = "2",
+                            text = "World"
+                        )
+                    )
+                )
+            )
+        }
+
+    }
+})