diff --git a/jest.config.base.js b/jest.config.base.js
index 942e96d..a9779da 100644
--- a/jest.config.base.js
+++ b/jest.config.base.js
@@ -9,7 +9,6 @@ const testServerLoaderPath = path.resolve(__dirname, './config/jest-test-server.
 // https://jestjs.io/docs/en/configuration.html
 
 const base = {
-  cache: false,
   clearMocks: true,
   collectCoverage: true,
   coverageDirectory: './.coverage',
diff --git a/packages/overlayscrollbars/src/overlayscrollbars/lifecycles/index.ts b/packages/overlayscrollbars/src/lifecycles/lifecycleBase.ts
similarity index 98%
rename from packages/overlayscrollbars/src/overlayscrollbars/lifecycles/index.ts
rename to packages/overlayscrollbars/src/lifecycles/lifecycleBase.ts
index efde8ab..8d978a9 100644
--- a/packages/overlayscrollbars/src/overlayscrollbars/lifecycles/index.ts
+++ b/packages/overlayscrollbars/src/lifecycles/lifecycleBase.ts
@@ -1,7 +1,7 @@
 import {
   CacheUpdateInfo,
   CachePropsToUpdate,
-  CacheChanged,
+  CacheUpdated,
   OptionsWithOptionsTemplate,
   OptionsValidated,
   transformOptions,
@@ -41,7 +41,7 @@ export const createLifecycleBase = <O, C>(
   defaultOptionsWithTemplate: OptionsWithOptionsTemplate<Required<O>>,
   cacheUpdateInfo: CacheUpdateInfo<C>,
   initialOptions: O | undefined,
-  updateFunction: (changedOptions: OptionsValidated<O>, changedCache: CacheChanged<C>) => any
+  updateFunction: (changedOptions: OptionsValidated<O>, changedCache: CacheUpdated<C>) => any
 ): LifecycleBase<O, C> => {
   const { _template: optionsTemplate, _options: defaultOptions } = transformOptions<Required<O>>(defaultOptionsWithTemplate);
   const options: Required<O> = assignDeep({}, defaultOptions, validateOptions<O>(initialOptions || ({} as O), optionsTemplate)._validated);
diff --git a/packages/overlayscrollbars/src/overlayscrollbars/lifecycles/StructureLifecycle.ts b/packages/overlayscrollbars/src/lifecycles/structureLifecycle.ts
similarity index 93%
rename from packages/overlayscrollbars/src/overlayscrollbars/lifecycles/StructureLifecycle.ts
rename to packages/overlayscrollbars/src/lifecycles/structureLifecycle.ts
index ab4b3fe..e70e328 100644
--- a/packages/overlayscrollbars/src/overlayscrollbars/lifecycles/StructureLifecycle.ts
+++ b/packages/overlayscrollbars/src/lifecycles/structureLifecycle.ts
@@ -12,10 +12,10 @@ import {
   optionsTemplateTypes as oTypes,
   OptionsTemplateValue,
 } from 'support';
-import { createLifecycleBase, Lifecycle } from 'overlayscrollbars/lifecycles';
+import { createLifecycleBase, Lifecycle } from 'lifecycles/lifecycleBase';
 import { getEnvironment, Environment } from 'environment';
-import { createSizeObserver } from 'overlayscrollbars/observers/SizeObserver';
-import { createTrinsicObserver } from 'overlayscrollbars/observers/TrinsicObserver';
+import { createSizeObserver } from 'observers/sizeObserver';
+import { createTrinsicObserver } from 'observers/trinsicObserver';
 
 export type OverflowBehavior = 'hidden' | 'scroll' | 'visible-hidden' | 'visible-scroll';
 export interface StructureLifecycleOptions {
diff --git a/packages/overlayscrollbars/src/observers/index.scss b/packages/overlayscrollbars/src/observers/index.scss
new file mode 100644
index 0000000..e69de29
diff --git a/packages/overlayscrollbars/src/overlayscrollbars/observers/SizeObserver.ts b/packages/overlayscrollbars/src/observers/sizeObserver.ts
similarity index 100%
rename from packages/overlayscrollbars/src/overlayscrollbars/observers/SizeObserver.ts
rename to packages/overlayscrollbars/src/observers/sizeObserver.ts
diff --git a/packages/overlayscrollbars/src/overlayscrollbars/observers/TrinsicObserver.ts b/packages/overlayscrollbars/src/observers/trinsicObserver.ts
similarity index 95%
rename from packages/overlayscrollbars/src/overlayscrollbars/observers/TrinsicObserver.ts
rename to packages/overlayscrollbars/src/observers/trinsicObserver.ts
index 6acfa32..a037e0c 100644
--- a/packages/overlayscrollbars/src/overlayscrollbars/observers/TrinsicObserver.ts
+++ b/packages/overlayscrollbars/src/observers/trinsicObserver.ts
@@ -1,5 +1,5 @@
 import { createDOM, offsetSize, jsAPI, runEach, prependChildren, removeElements } from 'support';
-import { createSizeObserver } from 'overlayscrollbars/observers/SizeObserver';
+import { createSizeObserver } from 'observers/sizeObserver';
 
 const classNameTrinsicObserver = 'os-trinsic-observer';
 const IntersectionObserverConstructor = jsAPI('IntersectionObserver');
diff --git a/packages/overlayscrollbars/src/support/cache/cache.ts b/packages/overlayscrollbars/src/support/cache/cache.ts
index 28ca662..f27e827 100644
--- a/packages/overlayscrollbars/src/support/cache/cache.ts
+++ b/packages/overlayscrollbars/src/support/cache/cache.ts
@@ -1,4 +1,6 @@
-import { each, keys, isArray, isString } from 'support';
+import { isArray, isString } from 'support/utils/types';
+import { keys } from 'support/utils/object';
+import { each } from 'support/utils/array';
 
 interface CacheEntry<T> {
   _current?: T;
@@ -10,22 +12,22 @@ type Cache<T> = {
   [P in keyof T]: CacheEntry<T[P]>;
 };
 
-type UpdateCacheProp<T> = <P extends keyof T>(prop: P, value: T[P], compare: CacheEqualFunction<T, P> | null) => void;
+type UpdateCacheProp<T> = <P extends keyof T>(prop: P, value: T[P], compare: EqualCachePropFunction<T, P> | null) => void;
+
+type UpdateCachePropFunction<T, P extends keyof T> = (current?: T[P], previous?: T[P]) => T[P];
+
+type EqualCachePropFunction<T, P extends keyof T> = (a?: T[P], b?: T[P]) => boolean;
 
 export type CachePropsToUpdate<T> = Array<keyof T> | keyof T;
 
-export type CacheUpdateFunction<T, P extends keyof T> = (current?: T[P], previous?: T[P]) => T[P];
+export type CacheUpdate<T> = (propsToUpdate?: CachePropsToUpdate<T>, force?: boolean) => CacheUpdated<T>;
 
-export type CacheEqualFunction<T, P extends keyof T> = (a?: T[P], b?: T[P]) => boolean;
-
-export type CacheChange<T> = (propsToUpdate?: CachePropsToUpdate<T>, force?: boolean) => CacheChanged<T>;
-
-export type CacheChanged<T> = {
+export type CacheUpdated<T> = {
   [P in keyof T]?: T[P];
 };
 
 export type CacheUpdateInfo<T> = {
-  [P in keyof T]: CacheUpdateFunction<T, P> | [CacheUpdateFunction<T, P>, CacheEqualFunction<T, P>];
+  [P in keyof T]: UpdateCachePropFunction<T, P> | [UpdateCachePropFunction<T, P>, EqualCachePropFunction<T, P>];
 };
 
 /**
@@ -46,7 +48,7 @@ export type CacheUpdateInfo<T> = {
  * @returns A function which can be called with wither one ar an array of properties which shall be updated. Optionally it can be called with the force param.
  * This function returns a object which contains all changed cache properties, if a property isn't in this object it means that it didn't change.
  */
-export const createCache = <T>(cacheUpdateInfo: CacheUpdateInfo<T>): CacheChange<T> => {
+export const createCache = <T>(cacheUpdateInfo: CacheUpdateInfo<T>): CacheUpdate<T> => {
   const cache: Cache<T> = {} as T;
   const allProps: Array<keyof T> = keys(cacheUpdateInfo) as Array<keyof T>;
 
@@ -62,8 +64,8 @@ export const createCache = <T>(cacheUpdateInfo: CacheUpdateInfo<T>): CacheChange
     cache[prop]._changed = equal ? !equal(curr, value) : curr !== value;
   };
 
-  const flush = (force?: boolean): CacheChanged<T> => {
-    const result: CacheChanged<T> = {} as CacheChanged<T>;
+  const flush = (force?: boolean): CacheUpdated<T> => {
+    const result: CacheUpdated<T> = {} as CacheUpdated<T>;
 
     each(allProps, (prop: keyof T) => {
       if (cache[prop]._changed || force) {
diff --git a/packages/overlayscrollbars/tests/puppeteer/Environment/index.test.ts b/packages/overlayscrollbars/tests/puppeteer/Environment/index.test.ts
index aefbea9..575793f 100644
--- a/packages/overlayscrollbars/tests/puppeteer/Environment/index.test.ts
+++ b/packages/overlayscrollbars/tests/puppeteer/Environment/index.test.ts
@@ -8,8 +8,8 @@ describe('Environment', () => {
 
   it('should be titled "Environment"', async () => {
     // @ts-ignore
-    const a: Environment = await page.evaluate(() => window.Environment.envInstance);
+    const a: Environment = await page.evaluate(() => window.environment.envInstance);
     console.log(a);
-    await expect(page.title()).resolves.toMatch('Environment');
+    await expect(page.title()).resolves.toMatch('environment');
   });
 });
diff --git a/packages/overlayscrollbars/tests/puppeteer/StructureLifecycle/index.browser.ts b/packages/overlayscrollbars/tests/puppeteer/lifecycles/structureLifecycle/index.browser.ts
similarity index 67%
rename from packages/overlayscrollbars/tests/puppeteer/StructureLifecycle/index.browser.ts
rename to packages/overlayscrollbars/tests/puppeteer/lifecycles/structureLifecycle/index.browser.ts
index a3f2d0b..ea88a83 100644
--- a/packages/overlayscrollbars/tests/puppeteer/StructureLifecycle/index.browser.ts
+++ b/packages/overlayscrollbars/tests/puppeteer/lifecycles/structureLifecycle/index.browser.ts
@@ -1,6 +1,6 @@
 import 'overlayscrollbars.scss';
 import './index.scss';
-import { createStructureLifecycle } from 'overlayscrollbars/lifecycles/StructureLifecycle';
+import { createStructureLifecycle } from 'lifecycles/structureLifecycle';
 
 const targetElm = document.querySelector('#target') as HTMLElement;
 
diff --git a/packages/overlayscrollbars/tests/puppeteer/StructureLifecycle/index.html b/packages/overlayscrollbars/tests/puppeteer/lifecycles/structureLifecycle/index.html
similarity index 100%
rename from packages/overlayscrollbars/tests/puppeteer/StructureLifecycle/index.html
rename to packages/overlayscrollbars/tests/puppeteer/lifecycles/structureLifecycle/index.html
diff --git a/packages/overlayscrollbars/tests/puppeteer/StructureLifecycle/index.scss b/packages/overlayscrollbars/tests/puppeteer/lifecycles/structureLifecycle/index.scss
similarity index 100%
rename from packages/overlayscrollbars/tests/puppeteer/StructureLifecycle/index.scss
rename to packages/overlayscrollbars/tests/puppeteer/lifecycles/structureLifecycle/index.scss
diff --git a/packages/overlayscrollbars/tests/puppeteer/StructureLifecycle/index.test.ts b/packages/overlayscrollbars/tests/puppeteer/lifecycles/structureLifecycle/index.test.ts
similarity index 63%
rename from packages/overlayscrollbars/tests/puppeteer/StructureLifecycle/index.test.ts
rename to packages/overlayscrollbars/tests/puppeteer/lifecycles/structureLifecycle/index.test.ts
index 45d7920..019d7b2 100644
--- a/packages/overlayscrollbars/tests/puppeteer/StructureLifecycle/index.test.ts
+++ b/packages/overlayscrollbars/tests/puppeteer/lifecycles/structureLifecycle/index.test.ts
@@ -8,8 +8,8 @@ describe('StructureLifecycle', () => {
 
   it('should be titled "Environment"', async () => {
     // @ts-ignore
-    const a: Environment = await page.evaluate(() => window.Environment.envInstance);
+    const a: Environment = await page.evaluate(() => window.structureLifecycle.envInstance);
     console.log(a);
-    await expect(page.title()).resolves.toMatch('Environment');
+    await expect(page.title()).resolves.toMatch('structureLifecycle');
   });
 });
diff --git a/packages/overlayscrollbars/tests/puppeteer/SizeObserver/index.browser.ts b/packages/overlayscrollbars/tests/puppeteer/observers/sizeObserver/index.browser.ts
similarity index 98%
rename from packages/overlayscrollbars/tests/puppeteer/SizeObserver/index.browser.ts
rename to packages/overlayscrollbars/tests/puppeteer/observers/sizeObserver/index.browser.ts
index 8fe0d0e..43d87fc 100644
--- a/packages/overlayscrollbars/tests/puppeteer/SizeObserver/index.browser.ts
+++ b/packages/overlayscrollbars/tests/puppeteer/observers/sizeObserver/index.browser.ts
@@ -6,7 +6,7 @@ import { generateSelectCallback, iterateSelect } from '@/testing-browser/Select'
 import { setTestResult } from '@/testing-browser/TestResult';
 import { hasDimensions, offsetSize, WH, style } from 'support';
 
-import { createSizeObserver } from 'overlayscrollbars/observers/SizeObserver';
+import { createSizeObserver } from 'observers/sizeObserver';
 
 let sizeIterations = 0;
 let directionIterations = 0;
diff --git a/packages/overlayscrollbars/tests/puppeteer/SizeObserver/index.html b/packages/overlayscrollbars/tests/puppeteer/observers/sizeObserver/index.html
similarity index 100%
rename from packages/overlayscrollbars/tests/puppeteer/SizeObserver/index.html
rename to packages/overlayscrollbars/tests/puppeteer/observers/sizeObserver/index.html
diff --git a/packages/overlayscrollbars/tests/puppeteer/SizeObserver/index.scss b/packages/overlayscrollbars/tests/puppeteer/observers/sizeObserver/index.scss
similarity index 100%
rename from packages/overlayscrollbars/tests/puppeteer/SizeObserver/index.scss
rename to packages/overlayscrollbars/tests/puppeteer/observers/sizeObserver/index.scss
diff --git a/packages/overlayscrollbars/tests/puppeteer/SizeObserver/index.test.ts b/packages/overlayscrollbars/tests/puppeteer/observers/sizeObserver/index.test.ts
similarity index 100%
rename from packages/overlayscrollbars/tests/puppeteer/SizeObserver/index.test.ts
rename to packages/overlayscrollbars/tests/puppeteer/observers/sizeObserver/index.test.ts
diff --git a/packages/overlayscrollbars/tests/puppeteer/TrinsicObserver/index.browser.ts b/packages/overlayscrollbars/tests/puppeteer/observers/trinsicObserver/index.browser.ts
similarity index 98%
rename from packages/overlayscrollbars/tests/puppeteer/TrinsicObserver/index.browser.ts
rename to packages/overlayscrollbars/tests/puppeteer/observers/trinsicObserver/index.browser.ts
index bdfbbf5..0912d8b 100644
--- a/packages/overlayscrollbars/tests/puppeteer/TrinsicObserver/index.browser.ts
+++ b/packages/overlayscrollbars/tests/puppeteer/observers/trinsicObserver/index.browser.ts
@@ -7,7 +7,7 @@ import { timeout } from '@/testing-browser/timeout';
 import { setTestResult } from '@/testing-browser/TestResult';
 import { offsetSize } from 'support';
 
-import { createTrinsicObserver } from 'overlayscrollbars/observers/TrinsicObserver';
+import { createTrinsicObserver } from 'observers/trinsicObserver';
 
 const waitForOptions = {
   onTimeout(error: Error): Error {
diff --git a/packages/overlayscrollbars/tests/puppeteer/TrinsicObserver/index.html b/packages/overlayscrollbars/tests/puppeteer/observers/trinsicObserver/index.html
similarity index 100%
rename from packages/overlayscrollbars/tests/puppeteer/TrinsicObserver/index.html
rename to packages/overlayscrollbars/tests/puppeteer/observers/trinsicObserver/index.html
diff --git a/packages/overlayscrollbars/tests/puppeteer/TrinsicObserver/index.scss b/packages/overlayscrollbars/tests/puppeteer/observers/trinsicObserver/index.scss
similarity index 100%
rename from packages/overlayscrollbars/tests/puppeteer/TrinsicObserver/index.scss
rename to packages/overlayscrollbars/tests/puppeteer/observers/trinsicObserver/index.scss
diff --git a/packages/overlayscrollbars/tests/puppeteer/TrinsicObserver/index.test.ts b/packages/overlayscrollbars/tests/puppeteer/observers/trinsicObserver/index.test.ts
similarity index 100%
rename from packages/overlayscrollbars/tests/puppeteer/TrinsicObserver/index.test.ts
rename to packages/overlayscrollbars/tests/puppeteer/observers/trinsicObserver/index.test.ts
diff --git a/rollup.config.base.js b/rollup.config.base.js
index 37d2a65..010f18d 100644
--- a/rollup.config.base.js
+++ b/rollup.config.base.js
@@ -27,7 +27,7 @@ const rollupConfigDefaults = {
 };
 
 const legacyBabelConfig = {
-  exclude: isTestEnv ? [/\/core-js\//] : [],
+  exclude: isTestEnv ? [/\/core-js\//, /\/@testing-library\//] : [],
   presets: [
     [
       '@babel/preset-env',