Senior Full-Stack Engineer — Kotlin / Node.js / Playwright (Contract to Complete Production Platform)

Senior full-stack engineer needed for a contract role completing a production platform. The ideal candidate has 5+ years of full-stack engineering experience with demonstrated ability to walk into an inherited codebase and ship features within the first week. You should have production experience with Kotlin and Spring Boot, or strong Java / Spring Boot with willingness to ramp on Kotlin quickly. Deep Node.js fluency with modern async/await patterns and ES modules is required, along with hands-on Playwright experience for browser automation at production scale. Frontend experience should include React, TypeScript, and Tailwind with the ability to extend and maintain existing component architectures rather than rebuild them. On the data layer, you should be comfortable with PostgreSQL (query optimization, schema design), Redis (caching, pub/sub), and have working familiarity with Neo4j or graph databases. Kafka experience for event-driven architecture is a plus. You should be fluent with Docker and docker-compose for local and production environments, and comfortable reading existing CI/CD pipelines without needing to rework them. Preferred experience includes Appium or ADB for Android device automation, n8n for workflow orchestration, and Prometheus with Grafana for observability. These aren't strict

but candidates with production exposure to these tools will ramp faster. Experience building or operating automation systems that run at scale — social media, e-commerce, data scraping, or similar — is a strong plus. Understanding of anti-detection patterns, proxy management, or device fingerprinting is directly relevant. The right candidate uses AI-assisted development tools like Claude Code or Cursor as a core part of their workflow, not as an occasional supplement. You should be able to describe specifically how you use these tools — for scaffolding, for unfamiliar code exploration, for test generation — rather than just listing them as skills. Engineers who rely entirely on AI without strong fundamentals will not succeed on this project. Engineers who refuse to use AI tools will work too slowly for the timeline. What matters most, beyond the stack, is the mentality. You should be comfortable shipping small and often rather than planning for weeks before committing code. You should ask direct questions when stuck rather than silently burning time. You should be able to describe the last production system you inherited — what state it was in, what you shipped in your first month, and what you chose not to touch. If you prefer greenfield builds, extensive refactoring before shipping features, or roles where you set architectural direction from scratch, this isn't the right fit. This is a completion role, not a reconstruction role.