Senior Software Engineer - Activation

Join our global force of 400+ innovators, blending the latest in tech with the greatest in soundtracking, from our Stockholm HQ to offices in London, New York, Los Angeles, Berlin, Paris, Oslo, and Seoul. We're an industry leader with a startup mentality. We take what we do seriously, but we don't take ourselves too seriously. Creating and collaborating to transform the sound of streaming, content, and culture. Come join us, and let the world feel your work. As a Senior Software Engineer, you will play a crucial role in the Activation team, which owns the first minutes a new user spends inside Epidemic Sound. Your role will be to improve new user onboarding through customised, data-driven journeys — building both the user-facing flows and the signal-based systems behind them. You will join a friendly and highly collaborative team that works in fast feedback loops, with AI-assisted workflows such as Claude Code as part of everyday engineering, and you will work alongside product, design, marketing, data and analytics colleagues across the Growth domain, taking ambiguous problems from an idea to a shipped experiment. Your Key Responsibilities Include

• Build user-facing onboarding flows, contextual nudges and interactive elements across logged-in and logged-out experiences.
• Develop systems that read early-funnel signals to understand user intent and route new users to relevant product paths.
• Deliver end to end across the stack, in React and TypeScript on the frontend and Python, Go or Kotlin on the backend.
• Run A/B tests and fast feedback loops so improvements to activation are measured rather than assumed.
• Own the observability, reliability and developer experience of the systems the Activation team runs.

Requirements

• 4+ years of experience in React, TypeScript and modern CSS and HTML.
• Experience in backend development (Python, Go or Kotlin).
• A proven track record in full-stack product development, including backend-for-frontend patterns and event-driven systems.
• Experience in analytics instrumentation and experimentation, covering event tracking, A/B testing, feature flags and using data to judge product impact.
• Comfortable in working AI-first, with agentic tools as part of everyday craft.
• Strong collaborative skills and being able to comfortably drive ambiguous problems towards clarity and implementation.

It would also be music to our ears if you have deep experience architecting scalable web applications in React and TypeScript, including server-side rendering, frontend architecture and performance work, along with familiarity with observability tooling and experimentation and product analytics platforms. Equal opportunity employer We believe that bringing people together from different backgrounds, experiences and perspectives makes for a healthy workplace, a more successful business and a better world. We value diversity and encourage everyone to come and soundtrack the world with us. Application Ready to make the world feel your work? Please apply, in English.