Sylwia Laskowska

  1. JS Poland
  2. / Speaker

JavaScript Conference 2025 (Warsaw & Online)
Learn from the BestMeet Sylwia Laskowska

Sylwia Laskowska

Rewrite or refactor? How to safely move legacy apps to modern frameworks.

Sooner or later, every team faces the same question: how do we migrate from legacy code to a modern framework? Should we take the “big bang” approach and rewrite everything from scratch, or should we migrate progressively, piece by piece? In this talk, I’ll share real-world stories from large-scale frontend migrations and highlight the trade-offs of both strategies. We’ll explore the risks of freezing development for months, the complexity of running two worlds in parallel, and the decision-making criteria that help teams pick the right path.

Sylwia Laskowska - Senior JavaScript Developer, Atos | Poland

Sylwia is a Senior JavaScript Developer with over a decade of experience. She has worked on a wide range of projects, from greenfield applications to complex migrations. As a Tech Lead, she focuses on helping teams modernize legacy codebases and build sustainable solutions.

Learn from the Best Featured Speakers

Meet our first speakers for 2025! More to be announced soon. Interested in joining? Apply below!


Call For Papers 2025

Companies that support the JavaScript ecosystem
Our Sponsors 2026

By becoming a sponsor of JS Poland, you gain a unique opportunity to showcase your company and products to hundreds of experienced JavaScript developers, engineers, and tech leaders from across Europe. This kind of exposure can boost visibility, strengthen your brand within the JS community, and help you attract top engineering talent. To learn more about our sponsorship opportunities, please fill in the form.



Become A Sponsor

Join our mailing list

Sign up to receive updates about JS Poland, including workshops, speaker previews, ticket launches, JS Awards, JavaScript Master Podcast, Behind the Code Magazine, CFP details and other exclusive content. We won’t spam you and will only send you emails we genuinely think you’ll find interesting. You can unsubscribe at any time and you can find more information here.