AI Builder: Hands-On Agent-First B2B SaaS Builder

Everfield; Polska; On-site; PLN 180,000 - 300,000; Full time

Job summary

Everfield is hiring an AI Builder to be the hands‑on engineering force inside the product team. You’ll jump into BU codebases, prototype with agentic tools, and ship agent‑first features end to end on real products with real customers.

You’ll work closely with BU engineers, prototype with customers, and deliver production‑ready code with documentation and a concise technical narrative for BU leadership.

Qualifications

• Senior engineer with shipped software to real users.
• Founder or near-founder experience in tech startups (B2B SaaS preferred).
• AI-native ways of working with agentic coding tools and a view on tool integration.
• Polyglot pragmatism across stacks and languages in production.
• Comfort with legacy/mature product codebases and making informed build choices.

Responsibilities

• Build agent-first products end to end inside Everfield's BU codebases. Spec, prototype, ship, iterate, hand off.
• Drop into BU codebases and become productive in days; build backend, data platforms, workflow tools, and occasional UI-heavy products.
• Run agentic coding with Claude Code, Codex, SpecKit as the default mode of work; create tools where none exist.
• Prototype with BU customers and iterate based on actual usage.
• Work with BU engineering teams to ensure transfer of knowledge and maintainability after handoff.
• Translate validated ideas into shipped products within weeks; provide production-ready code and documentation.

Skills

Senior engineer

Founder experience

AI-native workflows

Polyglot programming

Customer exposure

Education

Engineering degree

Tools

Claude Code

Codex

SpecKit

Job description

Everfield is hiring an AI Builder to be the hands‑on engineering force inside the product team. You’ll jump into BU codebases, prototype with agentic tools, and ship agent‑first features end to end on real products with real customers.

You’ll work closely with BU engineers, prototype with customers, and deliver production‑ready code with documentation and a concise technical narrative for BU leadership.