Full-Stack Engineer (Java/Spring + React) 3asoft $$$$

Madfish

Madfish

Software Engineering

Ukraine · Europe

Posted on May 21, 2026

About the Project

A B2B SaaS platform purpose-built for a niche vertical in the construction industry is looking for an experienced full-stack engineer to join an early-stage team. You'll take end-to-end ownership of features - from database schema and backend API through to frontend UI and E2E tests - while also raising the overall quality and polish of the product. The engineering team is currently led by a CTO, so you'll be working closely with the product direction and have real influence over technical decisions.

Tech Stack

Backend: Java 21, Spring Boot 3.2, Gradle, PostgreSQL 16, Flyway, Redis 7
Frontend: React 18, Vite, Tailwind CSS, Shadcn/UI, TanStack Query
Processing: Python 3.12+, FastAPI, LLM integrations
Infrastructure: Docker, Keycloak, Azure Blob Storage, Azure Service Bus, AWS Bedrock (EU)
Testing: Playwright, JUnit, pytest

Responsibilities

- Own features end to end - take a spec through backend API design, database modeling, frontend implementation, and into production with full test coverage
- Consistently raise the UI/UX quality of the platform: components, design tokens, dialogs
- Write Playwright E2E tests as a natural part of delivery; critical flows ship with coverage, not after
- Model domains and write non-trivial queries in PostgreSQL; think about data structure early
- Participate in code review and contribute to a shared standard for code quality
- Use AI coding tools (Cursor, Claude Code, Copilot, or equivalent) as an active part of your daily workflow
- Contribute to the LLM processing engine if that's a direction you want to grow into (opportunity, not requirement)

What We're Looking For

- 3+ years of commercial full-stack experience; Java/Spring Boot is the primary backend stack, React 18 is the primary frontend
- Writes E2E tests as part of delivery, not as an afterthought
- Playwright experience or equivalent required
- Solid relational database skills: comfortable with domain modeling and queries that go beyond simple CRUD
- Uses AI coding tools daily and can speak concretely to how they've accelerated their work
- UI/UX eye - know the difference between functional and polished, and care about closing that gap
- Self-directed in a startup context: able to find priorities independently, ask the right questions, and move without hand-holding
- Strong written and spoken English - the team communicates clearly and expects the same

Nice to Have

- Hands-on experience with Tailwind + Shadcn specifically
- Experience with Python/FastAPI in a production context
- Familiarity with Azure (Blob Storage, Service Bus) or AWS Bedrock
- Keycloak or another OIDC/SAML auth provider in production
- Practical AI engineering experience: evals, prompt structure, structured output, RAG, hallucination mitigation
- shipped LLM-powered features in production
- Domain exposure to construction, AEC, or B2B SaaS