diff --git a/packages/api-derive/src/index.spec.ts b/packages/api-derive/src/index.spec.ts
index ed1df43b74..28c58f76c0 100644
--- a/packages/api-derive/src/index.spec.ts
+++ b/packages/api-derive/src/index.spec.ts
@@ -22,13 +22,6 @@ const testFunction = (api: ApiInterface$Rx) => {
       it('should return an Observable', () => {
         expect((api.derive[section][method] as any)(...inputs)).toBeInstanceOf(Observable);
       });
-
-      it('should be memoized', () => {
-        const first = (api.derive[section][method] as any)(...inputs);
-        const second = (api.derive[section][method] as any)(...inputs);
-
-        expect(first).toBe(second);
-      });
     });
   };
 };
diff --git a/packages/api-derive/src/index.ts b/packages/api-derive/src/index.ts
index 824c818da3..df464424e1 100644
--- a/packages/api-derive/src/index.ts
+++ b/packages/api-derive/src/index.ts
@@ -5,7 +5,6 @@
 import { Observable } from 'rxjs';
 import { ApiInterface$Rx } from '@polkadot/api/types';
 
-import { cache } from './util/cache';
 import * as accounts from './accounts';
 import * as balances from './balances';
 import * as chain from './chain';
@@ -49,13 +48,8 @@ function injectFunctions (api: ApiInterface$Rx, derive: Derive, functions: Deriv
     const result = derive[sectionName as keyof Derive] = derive[sectionName as keyof Derive] || {};
 
     Object.keys(section).forEach((methodName) => {
-      // Create cache for the section_method function
       // @ts-ignore No idea how to make this work...
-      const cached = cache(section[methodName as keyof section]);
-
-      // Add this cached function into the result
-      // @ts-ignore No idea how to make this work...
-      result[methodName as keyof section] = cached(api);
+      result[methodName as keyof section] = section[methodName as keyof section](api);
     });
   });
 
diff --git a/packages/api-derive/src/util/cache.spec.ts b/packages/api-derive/src/util/cache.spec.ts
deleted file mode 100644
index 8c64ff4682..0000000000
--- a/packages/api-derive/src/util/cache.spec.ts
+++ /dev/null
@@ -1,30 +0,0 @@
-// Copyright 2017-2019 @polkadot/api-derive authors & contributors
-// This software may be modified and distributed under the terms
-// of the Apache-2.0 license. See the LICENSE file for details.
-
-import { ApiInterface$Rx } from '@polkadot/api/types';
-
-import { cache } from './cache';
-
-describe('cache', () => {
-  const f = cache((api: ApiInterface$Rx) => (a: number, b: number) => [api, a, b]);
-  const api = {} as ApiInterface$Rx;
-
-  it('should hit cache when all arguments are the same', () => {
-    const first = f(api)(2, 3);
-    const second = f(api)(2, 3);
-
-    expect(first).toBe(second);
-  });
-
-  it('should not hit cache when some arguments are not the same', () => {
-    const first = f(api)(2, 3);
-    const second1 = f(api)(5, 3);
-    const second2 = f(api)(2, 5);
-    const second3 = f({} as ApiInterface$Rx)(2, 3);
-
-    expect(first).not.toBe(second1);
-    expect(first).not.toBe(second2);
-    expect(first).not.toBe(second3);
-  });
-});
diff --git a/packages/api-derive/src/util/cache.ts b/packages/api-derive/src/util/cache.ts
deleted file mode 100644
index 0f647985ee..0000000000
--- a/packages/api-derive/src/util/cache.ts
+++ /dev/null
@@ -1,31 +0,0 @@
-// Copyright 2017-2019 @polkadot/api-derive authors & contributors
-// This software may be modified and distributed under the terms
-// of the Apache-2.0 license. See the LICENSE file for details.
-
-import memoizee from 'memoizee';
-import { ApiInterface$Decorated } from '@polkadot/api/types';
-import { Codec } from '@polkadot/types/types';
-import { Observable } from 'rxjs';
-/**
- * Create memoization for a 2-currified function.
- *
- * @param fn - The function to memoize.
- * @param map - The Map used to cache function returns.
- * @example
- * ```javascript
- * const f = (api: ApiInterface$Rx) => (b: number) => a * b;
- * const cached = cache(f);
- * f(api)(1, 2);
- * f(api)(1); // Cache not hit
- * f({})(1, 2); // Cache not hit
- * f(api)(1, 2); // Cache hit
- * ```
- */
-export const cache = (fn: Function, map = new WeakMap()) => (api: ApiInterface$Decorated<Observable<Codec>, Observable<Codec>>) => {
-  if (!map.has(api)) {
-    const innerFn = fn(api);
-    map.set(api, memoizee(innerFn));
-  }
-
-  return map.get(api);
-};
diff --git a/packages/api-derive/test/e2e/promise.spec.ts b/packages/api-derive/test/e2e/promise.spec.ts
new file mode 100644
index 0000000000..9c5a8d0485
--- /dev/null
+++ b/packages/api-derive/test/e2e/promise.spec.ts
@@ -0,0 +1,32 @@
+// Copyright 2017-2019 @polkadot/api-derive authors & contributors
+// This software may be modified and distributed under the terms
+// of the Apache-2.0 license. See the LICENSE file for details.
+
+import ApiPromise from '@polkadot/api/promise/Api';
+import { BlockNumber } from '@polkadot/types';
+import { WsProvider } from '@polkadot/rpc-provider';
+
+const WS_LOCAL = 'ws://127.0.0.1:9944/';
+// const WS_POC3 = 'wss://poc3-rpc.polkadot.io/';
+
+describe.skip('derive e2e', () => {
+  let api: ApiPromise;
+
+  beforeAll(() => {
+    jest.setTimeout(30000);
+  });
+
+  beforeEach(async (done) => {
+    api = await ApiPromise.create(new WsProvider(WS_LOCAL));
+    done();
+  });
+
+  it('returns correct results', async () => {
+    // https://github.com/polkadot-js/api/issues/777
+    const block1 = await api.derive.chain.bestNumber();
+    await new Promise((resolve) => setTimeout(resolve, 15000));
+    const block2 = await api.derive.chain.bestNumber();
+
+    expect((block1 as BlockNumber).eq(block2)).toBe(false);
+  });
+});
diff --git a/packages/api-derive/test/e2e/derive.spec.ts b/packages/api-derive/test/e2e/rx.spec.ts
similarity index 97%
rename from packages/api-derive/test/e2e/derive.spec.ts
rename to packages/api-derive/test/e2e/rx.spec.ts
index 38bb6ac9b3..a725957449 100644
--- a/packages/api-derive/test/e2e/derive.spec.ts
+++ b/packages/api-derive/test/e2e/rx.spec.ts
@@ -1,4 +1,4 @@
-// Copyright 2017-2018 @polkadot/api-derive authors & contributors
+// Copyright 2017-2019 @polkadot/api-derive authors & contributors
 // This software may be modified and distributed under the terms
 // of the Apache-2.0 license. See the LICENSE file for details.
 
diff --git a/packages/types/src/type/NonceCompact.ts b/packages/types/src/type/NonceCompact.ts
index 0e9fd4d591..8c841fefb8 100644
--- a/packages/types/src/type/NonceCompact.ts
+++ b/packages/types/src/type/NonceCompact.ts
@@ -1,4 +1,4 @@
-// Copyright 2017-2018 @polkadot/types authors & contributors
+// Copyright 2017-2019 @polkadot/types authors & contributors
 // This software may be modified and distributed under the terms
 // of the Apache-2.0 license. See the LICENSE file for details.