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11/14/2025

Online

Testing Native Modules Reliably With JavaScript

Date

Friday, November 14, 2025

Time

Location

London, United Kingdom

Online

Testing Native Modules Reliably With JavaScript

Learn how React Native Harness bridges the gap between mocking and E2E testing: real device tests, full native access, Jest-style simplicity.

Date

14 November 2025

-

Time

Location

London, United Kingdom

Online

Testing Native Modules Reliably With JavaScript

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Organizer

Organizer

Presented

React Native London

@

Speakers

Speakers

Featuring

Michał Pierzchala

Principal Engineer

@

Callstack

Featuring

Michał Pierzchala

Principal Engineer

@

Callstack

Testing native modules in React Native can be challenging; mocking often hides real-world behavior, while full E2E test requires extra boilerplate and heavy tools. In this talk, Michał will make you familiar with React Native Harness. It offers a new middle ground: running tests directly on the simulator or device with full access to native modules, all while keeping a familiar Jest-style workflow. All in your favorite JavaScript.

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Testing Native Modules Reliably With JavaScript

Learn how React Native Harness bridges the gap between mocking and E2E testing: real device tests, full native access, Jest-style simplicity.

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