Senior AI Engineer (Core Engine)

At Keystone AI, code is our passion. Ever since we started back in 2000, we have been striving to make the world’s most robust and effective developer tools. By automating routine checks and corrections, our tools speed up production, freeing developers to grow, discover, and create. We are now building services and agentic tools that provide AI coding agents and end users with deeper context about codebases. Our code retrieval service already delivers meaningful improvements in agent speed and task performance, and we aim to push this further – extracting richer insights than snippets alone at the scale of several hundred thousand repositories. We are looking for an AI Engineer who can design and implement agentic tools from scratch, bring them to the end users, and make coding with agents smarter, faster, and more reliable. In this role, you will: Translate product needs into agentic tools and services and ship them to production. Scale prototypes to large numbers of users. Improve and test our semantic search service. Build evaluation pipelines for code retrieval and coding task performance. We’ll be happy to have you on our team if you have: At least five years of hands-on NLP experience. Experience in information retrieval systems. Strong experience in LLM prompt and tool engineering, as well as with AI agents. Solid programming skills in Python and/or Kotlin (and the willingness to learn the language you’re unfamiliar with). Experience building and operating production-grade software systems. We’d be especially thrilled if you have: Experience developing in Kotlin or Java. Previously worked with code intelligence (e.g. AST, symbol graphs). Why join Keystone AI? Strong base salary. We offer competitive pay that reflects your skills and experience. Flexible work location. Enjoy the freedom to work from home or from the office. Remote work. Spend up to 30 days per year working remotely from abroad. Extra time off. More days to relax, recharge, and do the things you love. Medical insurance allowance. Enjoy peace of mind for you and your family Learning and development opportunities. Access to conferences, courses, and language classes. Relocation support. We help make your move as smooth and stress-free as possible. (keep if relevant for the role) Language classes. Pick up the local language or sharpen your English skills. Fuel your day. Enjoy a hot meal or receive a lunch allowance on workdays. Mental health support. To help you feel your best, we provide easy access to professional mental health services. Sports benefit. Enjoy an on-site gym or sports club stipend. Internal events. Join company-wide celebrations and team gatherings. *Some benefits may vary depending on location. #LI-DNI #LI-DNI We are an equal opportunity employer We know great ideas can come from anyone, anywhere. That’s why we do our best to create an open and inclusive workplace – one that welcomes everyone regardless of their background, identity, religion, age, accessibility needs, or orientation. We process the data provided in your job application in accordance with the Recruitment Privacy Policy.