Senior Fullstack Engineer - Platforms & Partner Experience at spotify

Delivering the best Spotify experience possible. To as many people as possible. In as many moments as possible. That’s what the Experience team is all about. We use our understanding of how people engage with music, podcasts, and video to bring Spotify to life across every platform and device. If you enjoy building smooth, reliable playback experiences that reach millions every day, we’d love to have you join us. Spotify reaches listeners through a wide ecosystem of first-party and partner-built applications on web, desktop, mobile, and beyond. To support this variety, this team builds the shared playback, evaluation, and reliability foundations that power every streaming moment at Spotify. We’re looking for a Senior Software Engineer to join our Platforms & Partner Experience team. In this role, you’ll help build and evolve a reliable, high-performance media SDK that powers Spotify’s web and JavaScript surface. This SDK supports both first-party products and partner integrations, delivering consistent, high-quality playback and resilience across audio and video. This work will help millions of listeners and hundreds of partners experience seamless playback wherever Spotify plays. What You'll Do • Take end-to-end responsibility for playback and measurement for audio and video on web, meeting reliability goals for start success, time-to-first-frame, and smooth, stall-free sessions. • Develop and evolve the team architecture to support new media formats and maintain feature parity with native platforms. • Improve CI and observability systems through hermetic testing, synthetic canaries, SLO-based rollouts. • Collaborate with native other teams to define shared contracts, mocks, and conformance tests that ensure consistency across platforms. • Advance video reliability through ads fallback, AEC conformance, lossless playback on Cast, and multi-player coordination. • Build on our data and experimentation foundations by contributing to unified dashboards and reusable metrics templates. • Support teammates in playback architecture, streaming performance, and data instrumentation. Who You Are • Experience in Web or Playback Systems Engineering, with deep knowledge of modern JavaScript and TypeScript (ESNext, Web APIs, performance profiling). • You’re confident working with media playback APIs such as MediaSource Extensions, EME, WebRTC, HLS/DASH, and DRM, and you understand how to build for video streaming and measurement, including adaptive bitrate, buffering, and QoE metrics. • Ideally, you are familiar with CI systems and hermetic testing at scale, and you care about data instrumentation, from logging and metrics to dash boarding and observability. • Experience with native media stacks (Android/iOS, C++, Rust, or React Native bridges) is a strong plus • Knowledge of ads technology and fallback mechanisms in media delivery is also valuable. • Someone who works well in multi-functional environments and values teamwork as much as technical prowess, who cares about building inclusive, maintainable systems that serve a wide range of users and partners. Where You'll Be • This role is based in Stockholm or London. • We offer you the flexibility to work where you work best! There will be some in person meetings, but still allows for flexibility to work from home. Spotify is an equal opportunity employer. You are welcome at Spotify for who you are, no matter where you come from, what you look like, or what’s playing in your headphones. Our platform is for everyone, and so is our workplace. The more voices we have represented and amplified in our business, the more we will all thrive, contribute, and be forward-thinking! So bring us your personal experience, your perspectives, and your background. It’s in our differences that we will find the power to keep revolutionizing the way the world listens. At Spotify, we are passionate about inclusivity and making sure our entire recruitment process is accessible to everyone. We have ways to request reasonable accommodations during the interview process and help assist in what you need. If you need accommodations at any stage of the application or interview process, please let us know - we’re here to support you in any way we can. Spotify transformed music listening forever when we launched in 2008. Our mission is to unlock the potential of human creativity by giving a million creative artists the opportunity to live off their art and billions of fans the chance to enjoy and be passionate about these creators. Everything we do is driven by our love for music and podcasting. Today, we are the world’s most popular audio streaming subscription service.