Spec-Driven Agentic Full-Stack Engineer

Umain; Stockholms kommun; On-site; SEK 900,000 - 1,100,000; Full time

Job summary

Umain, a Stockholm-based digital product consultancy, seeks a senior full stack developer who can own specs, run multiple agents in parallel and ship client solutions end-to-end.

You will shape requirements with stakeholders, pick the right models, orchestrate agent work, and build secure, scalable applications with TypeScript, React/Next.js and Node.js while leveraging cloud and CI/CD tooling.

Qualifications

• 3+ years of professional full stack experience with TypeScript, React/Next.js, Node.js and web fundamentals.
• Hands-on experience delivering production software with coding agents (Claude Code, Codex, Cursor, or similar).
• Strong requirement-Definition ability: actors, use cases, features with clear acceptance criteria.
• Working spec-driven development practice with written specs and agent-built outcomes.
• Experience running multiple agents in parallel and coordinating their output.
• Practical experience using frontier and open-weight models and knowing when to use each.

Responsibilities

• Spec-driven delivery: define requirements, use cases and features with acceptance criteria.
• Agent orchestration: run and coordinate agent swarms, tie outputs to product goals.
• Model selection and mixing: route work by capability, cost, latency and data sensitivity.
• Full stack engineering: build secure, scalable web apps with TypeScript, React/Next.js and Node.js.
• Collaborate with clients and cross-functional teams to explain agentic delivery and trade-offs.

Skills

TypeScript

React

Next.js

Node.js

Web fundamentals

Spec driven development

Agent orchestration

Tools

Claude Code

Codex

Cursor

Tailwind CSS

Storybook

Design systems

Job description

Umain, a Stockholm-based digital product consultancy, seeks a senior full stack developer who can own specs, run multiple agents in parallel and ship client solutions end-to-end.

You will shape requirements with stakeholders, pick the right models, orchestrate agent work, and build secure, scalable applications with TypeScript, React/Next.js and Node.js while leveraging cloud and CI/CD tooling.