I am recruiting for a European software engineering company with 350+ professionals and a culture built on ownership, clean code, and transparency. They have spun up a small, startup-like team building a desktop control plane for local AI inference. The team already has an internal MVP, talks directly to potential users, and is moving fast toward open sourcing the tool. There is no bureaucracy. Senior/Staff Kotlin Desktop Engineer Poland · Remote · PLN 252k–373k + equity The role You will build a desktop application in Kotlin and Compose Desktop that deploys, configures, and manages AI models on local hardware, including NVIDIA Spark and DGX Spark. This is not a web app with a desktop wrapper. It is a native desktop control plane that handles model lifecycle, agent configuration, system load visualization, and LLM proxy routing. You will create the UI for model management dashboards and agent configuration screens. You will integrate with backend REST APIs to handle model deployment. You will implement configurations using TOML, JSON, and YAML, and build LLM proxy routing to connect coding agents like Claude Code and Codex to locally hosted models. You will package the application into native installers for Windows (MSI), Linux (DEB), and macOS (DMG). The team is small. You will own features end to end. Your decisions will ship quickly. You will work on problems that do not have Stack Overflow answers, navigate OS-specific quirks, and design solutions that have not been built this way before. What you need Strong Kotlin skills. This is the foundation of the role. Experience developing and maintaining build systems such as Gradle, Make, or Bazel. You have wrestled with genuinely hard build problems and solved them. Experience building or maintaining developer tooling. IDE plugins, CI/CD tooling, internal workflow automation, review tooling, or similar. Open source or DX-focused project experience counts. Solid command of Kotlin Coroutines and async programming under real-world conditions. Practical understanding of how Windows, macOS, and Linux differ at the level that matters for desktop applications. Preference for low-level, in-the-weeds technical work. You are comfortable with architecture but happiest when building. Ability to drive a feature independently while collaborating closely with a small team through code review. Fluent English. What you get PLN 252,000 to 373,000 annually, plus equity. Private healthcare. Home office reimbursement and flexible hybrid work model. Training package, language lessons, and in-house training. MyBenefit points. High ownership in a small team with no bureaucracy. Direct contact with users and fast iteration. Work on open source-bound tools for local AI inference. No "passionate self-starters." No "rockstars." No "game-changing." We need someone who writes solid Kotlin, solves hard build problems, and ships desktop software that manages real AI hardware. If that is you, apply with a short note about the hardest build problem you have solved and a link to any developer tooling you have built or maintained.Staff Kotlin Desktop Engineer