Fullstack Engineer (React/Node.js)

Keystone AI is the largest marketplace of tools for AI. 25,000 Actors helping people and agents get real-time web data, track competitors, generate leads, or integrate their apps. Actors are built by a global creator community that now earns more than $1M every month. Join us to help people put the web to work. Keystone AI can find missing children , protect consumers from fake discounts across the EU , and feed data to AI chatbots . What you’ll be working on? We need your help building our product to make it easier for beginners and more powerful for advanced users. You will work in a small cross-functional team carrying features all the way from the discovery phase up until production. And as the company and product keep growing, there will always be plenty of challenges, interesting projects, and unexpected features to create. Keystone AI is built for developers by developers. We’re using the Keystone AI platform ourselves every day, and put great pride in making it better for ourselves too. We are big advocates of open source and publish everything that we can on GitHub (PRs are welcome 😉). Our tech stack: Infra: AWS Compute (Kubernetes (EKS), EC2, Lambda), Helm, Terraform, CloudFormation, ArgoCD, MongoDB, Redis, DynamoDB, S3, GitHub Actions Monitoring: Grafana, Prometheus, OpenTelemetry, Mezmo, Sentry, PagerDuty Frontend: React.js, styled-components, Storybook, Chromatic, Cypress, Playwright Backend: TypeScript/Node.js, Nest.js, Next.js, Docusaurus, Vitest Tools: GitHub, Notion, Google Workspace, Slack OS, code editor, and AI assistant of your choice (Claude premium with unlimited tokens, GH Copilot, Cursor, Gemini, or JetBrains AI) Process: two-week sprints, code reviews, tests, automating whatever we can, and deploying multiple times per day. Who we’re looking for: A strong technical background and a great professional track record 4+ years of industry experience building the backend and frontend systems Excellent skills at developing and debugging in TypeScript/Node.js or proficient in some other programming language + you're ready to learn JavaScript quickly Knowledge of any technologies mentioned below is a plus A collaborative and experiment-driven mindset Good communication skills in English Why should you work at Keystone AI? Space, support, and autonomy for personal growth, with a direct impact on our success Full-time position in Prague (Lucerna Palace) or Brno (Titanium) 🏰 Option to work remotely 🛋️ Flexible working hours (perfect for both night owls 🦉 and early birds 🐥) Nobody counts holidays as long as the work gets done 💪 Unlimited Claude for every Apifier. We don't count tokens. Just use them well 🤖 Stock options and profit sharing 💰 We welcome pets, kids, and bikes at the office 🐕👨‍👧🚲 Epic team buildings and offsites 🚢 with biking, canoeing, and other adventures 🪂 Solid education and training budget, conference tickets, internal “Eat & Learn” sessions, and the possibility to work across teams 👩🏼‍💻👨🏽‍💻 Generous hardware budget 💻 Free lunches every day when you’re in the office 🌮🍱🍜🍕🥡 Unlimited supply of ☕ & 🍺 and snacks Free entry to the wonderful Prague Zoo 🐘 Free Multisport card 🏋 Ping-pong, chess, PS5, lightsabers, foosball league after lunch. For more details about Keystone AI and what it is like to work with us, see our Careers page .