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# To Me My X-Tests! - Mutation testing Strategies


- **Event:** World Congress 2026 Europe - Virtual Stage

## Description

Are you confident that your tests truly cover the behavior of your code, not just its lines? In the fast-paced world of JavaScript and TypeScript development, traditional coverage metrics often paint a deceptive picture of test suite effectiveness. This session will dive deep into Mutation Testing, a powerful and often underutilized technique that exposes hidden weaknesses in your tests and ultimately leads to more robust, reliable software.
We'll begin by demystifying the core concepts of mutation testing: what it is, how it works, and why it's a game-changer for ensuring code quality. Through practical, live-coded examples in JavaScript and TypeScript, attendees will learn how to:
Integrate mutation testing into their existing CI/CD pipelines using popular tools like Stryker Mutator.
Understand and interpret mutation testing reports, identifying areas where their test suite is weak and susceptible to subtle bugs.
Develop effective mutation strategies to target specific code areas, focusing on critical business logic and complex algorithms.
Leverage advanced configuration options to optimize mutation testing for different project sizes and team needs, balancing thoroughness with performance.
Explore common mutation operators relevant to JavaScript/TypeScript, from logical negation to arithmetic operator replacement, and understand their impact on test coverage.
This session is ideal for developers, QA engineers, and team leads who are passionate about building high-quality, maintainable JavaScript and TypeScript applications. Attendees will leave with actionable insights and practical skills to elevate their testing game, catch more bugs before they reach production, and confidently deliver resilient software. Join us to unlock the next level of test effectiveness and make your code truly bulletproof!

## Speaker

### [Jorge Gonzalez Pliego](https://www.wearedevelopers.com/@jorge-gonzalez-pliego)

Senior QA Engineer at Deutsche Bank


## Related talks at this congress

- [Old tools, new tricks](https://www.wearedevelopers.com/events/world-congress-2026-europe-virtual-stage/sessions/1579-old-tools-new-tricks) — Benjamin Bischoff
- [A Developer's Framework for Any Tool Migration](https://www.wearedevelopers.com/events/world-congress-2026-europe-virtual-stage/sessions/1476-a-developer-s) — Sérgio Sancho Pinto
- [How I Built QA from Scratch in a Scaling Startup - no fluff real life story](https://www.wearedevelopers.com/events/world-congress-2026-europe-virtual-stage/sessions/1552-how-i-built-qa-from) — Basia Karaagac
- [Improving quality with Agentic AI with Rovo Dev and Xray](https://www.wearedevelopers.com/events/world-congress-2026-europe-virtual-stage/sessions/1557-improving-quality) — Sergio Freire