AI-First Backend / Full-Stack Developer (Middle)

We're launching several IT products as a startup: our own CRM platform, bots and automation. We build first versions fast with the help of AI. We need a developer who ships new projects in days or a couple of weeks, then brings them to reliable and secure production. We operate in the EU, and our systems hold clients' personal data, so security and GDPR are the core of our work, not an add-on.

Location: Warsaw, preferably in the office. You can start remotely and move to the office later
Full-time: our projects will be your main job
Contract: B2B or Umowa Zlecenie (UZ)

What you'll do
Launch new projects quickly, from idea to first working version in days or 1–2 weeks (CRM platform, bots, automation, new products)
Build backend and integrations: APIs, background jobs, queues, PostgreSQL, third-party services
Review code written with AI (yours and others'): find and fix bugs, shape sound architecture, refactor and cover critical scenarios with tests
Bring existing projects to a reliable state, so they work in production and not only in a demo
Secure our projects: authentication and roles, storage of data and passwords, API protection, pre-release security checks, protection of clients' personal data under GDPR
Deploy and maintain projects: Linux, Docker, Git, CI/CD, backups, monitoring, updates, access management
Investigate incidents: find the root cause, restore service and prevent a repeat
Write a plan and timeline before each task and send short daily, weekly and monthly reports
Document what you build (service design, release and recovery procedures) so no system lives in one person's head

Requirements
Fluent Ukrainian or Russian (required), as it's the language of the team; English for documentation
2–3+ years of commercial development (backend or full-stack), with at least one project you took to real users yourself
Python or TypeScript (Node.js), PostgreSQL, APIs and integrations
Docker, Linux, Git, basic CI/CD: you deploy your own projects to a server
Security basics: no secrets in code, roles and access control, HTTPS, backups, no client data in logs
At least one year of daily work with AI tools (Claude Code, Cursor or similar) and the ability to verify AI-generated code instead of pasting it blindly
Ownership and transparency: you write your own plans and flag risks and mistakes immediately
Ability to explain to a non-technical person what is done, what isn't and why
Nice to have
Startup experience or your own launched projects
OWASP Top 10, security checks in CI, practical GDPR experience
Nginx, Cloudflare, Keycloak, monitoring
Telegram and WhatsApp bots, CRM integrations, telephony, AI agents and MCP

What we offer
Official employment (UZ or B2B)
Fixed rate + bonuses
Opportunities for career and financial growth
All the tools and equipment you need for work
Real products with live users, not training tasks
Real tasks at the intersection of infrastructure, security and development
Room to grow into architecture, security and infrastructure
Support and onboarding from day one
Multisport & Luxmed