Web SDK Developer (JavaScript)

We’re seeking a Web SDK Developer to lead the development of a reliable, scalable, and user-friendly JavaScript SDK used by customers worldwide.
Key Responsibilities:

• Design, build, and maintain the Acoustic Connect Web SDK, enabling enterprise-grade customer engagement and behavioral analytics features for web applications.
• Deliver high-quality, performant, and scalable SDK modules that integrate seamlessly with client websites and web applications across different browsers and environments.
• Take ownership of the full SDK lifecycle: from architectural design to public documentation and ongoing developer support.
• Continuously improve SDK codebase with best practices in modularity, testability, and maintainability.
• Refactor or retire legacy code and modules, aligning the SDK with modern JavaScript/TypeScript best practices and long-term maintainability.
• Proactively identify performance bottlenecks and lead improvements using browser profiling tools and web performance monitoring.

• Minimum 3-5 years of experience in JavaScript development.
• Proven ability to develop concise and lightweight SDKs with excellent performance and minimal impact on page load times.
• Deep understanding and experience with modern JavaScript (ES6+) and TypeScript.
• Strong knowledge of browser APIs, DOM manipulation, event handling, and cross-browser compatibility.
• Experience with build tools (Webpack, Rollup, Vite), package managers (npm, yarn), and module systems (CommonJS, ES modules, UMD).
• Knowledge of web app lifecycle, memory management, and performance optimization techniques specific to browser environments.
• Understanding of best practices for API versioning, backwards compatibility, and public SDK API design.
• Experience with testing frameworks (Jest, Mocha) and ensuring high code coverage through unit and integration testing.
• Keeping up to date with web ecosystem changes (new browser APIs, privacy changes like third-party cookie deprecation, security best practices) and applying them in SDK development.

What will set you apart?

• Experience with mobile SDK development (iOS, Android) or cross-platform frameworks (React Native, Flutter) is a bonus. (remove??? - could frighten potential candidates)
• Knowledge of web analytics, tracking technologies, identity management, and data privacy regulations (GDPR, CCPA).

Not checking all of the above boxes, but still feeling strong about a career in software development?

We want to hear from you anyway!

What We Offer:

• Direct impact on our product and three growth paths: Architect, Principal Software Engineer, or Manager.
• Remote or hybrid work from our Gdansk office (up to you!)
• Competitive benefits, including tax-deductible costs, MacBook Pro, medical and life insurance, meal allowance, and a Multisport card.