Senior Full-Stack Engineer (Backend Leaning)
Fairmarkit
Salary undisclosed
Need a reasonable accommodation to apply or interview? Contact us.
JobMinglr uses automated technology to recommend jobs based on profile information and job preferences. Match Score does not determine eligibility for a position, prevent a user from viewing or applying to a job, or make hiring decisions on behalf of an employer.
Description
Fairmarkit is the #1 autonomous sourcing platform revolutionizing the way all organizations buy & sell. Fairmarkit equips procurement teams with automation, AI, and GenAI so they can source more competitively at scale. Our solutions for tail spend and strategic sourcing help innovative procurement teams reduce cycle times, drive out costs, meet ESG/Diversity targets, and provide a better stakeholder experience to internal partners and suppliers. Fairmarkit has been recognized with awards by organizations such as Gartner and IDC, and is backed by strategic investors like Notable Capital, Insight Partners, 1984.VC, and Newfund.
Fairmarkit is the #1 autonomous sourcing platform revolutionizing the way all organizations buy & sell. Fairmarkit equips procurement teams with automation, AI, and GenAI so they can source more competitively at scale. Our solutions for tail spend and strategic sourcing help innovative procurement teams reduce cycle times, drive out costs, meet ESG/Diversity targets, and provide a better stakeholder experience to internal partners and suppliers. Fairmarkit has been recognized with awards by organizations such as Gartner and IDC, and is backed by strategic investors like Notable Capital, Insight Partners, 1984.VC, and Newfund.
The Role
We're hiring a senior engineer to help build the products our customers run their sourcing on -- events, supplier bids, awards, and the integrations that connect Fairmarkit to the ERPs and procurement suites they already use. The work is full-stack and leans back end. Most of your time goes into domain models, APIs, event-driven services and data that has to be right. Front-end engineers and dedicated designers work on the UI with you, so you need to be comfortable shipping a screen to production, but not necessarily an expert.
You won't be pinned to one feature. As priorities change you'll go where the work matters most, which might be sourcing workflows one quarter and an ERP integration the next. If you like learning a new domain quickly and leaving it better than you found it, you'll do well here.
We're not just "using AI". We build our own internal tooling, agentic systems and custom harnesses that improve how we collaborate, how we ship, and what we deliver to customers. If anything, AI raises the bar. The corners we used to cut to ship on time are work we can now hand to AI in parallel. We care about engineering excellence in the traditional sense: discipline, rigor, well-designed systems, and code we're glad to maintain a year from now. AI writes more of the syntax than it used to. Your judgment shows up everywhere else, from framing the problem and designing the system to reviewing what gets built, testing it and running it in production.
What You'll Do
- Design and build features end to end, from the domain model and API to the screen, with product managers, designers, front-end engineers, and QA
- Own the hard parts of the back end -- data models, service boundaries, event flows, and the integrations that move purchase data between Fairmarkit and our customers' systems
- Build with AI coding agents every day, and hold what they produce to the same standard as code you wrote by hand
- Review code carefully. Catch design problems before they ship, keep types honest, and design out whole classes of bugs instead of relying on tests to catch them
- Move across product areas as the roadmap shifts, ramp up fast, and write down what you learn for the next person
- Raise the bar around you. Mentor engineers who are new to an area, and help shape how we build software with AI
What You'll Bring
- A track record of shipping production software across the stack, with real depth on the back end
- Strong fundamentals in system design, clear interfaces, type safety and well-chosen tests
- Professional experience in at least one statically typed language such as Java, C#, Go, Kotlin, Scala or Rust, alongside TypeScript and Python
- Daily, hands-on use of AI coding tools, and the discipline to review, correct and own what they produce
- Comfort walking into an unfamiliar domain, asking good questions and finding the real constraint quickly
- The habit of explaining your decisions in writing (design docs, clear pull request descriptions, decision records) so teammates can follow and build on them without a meeting. We're building a culture of asynchronous, written communication, and we want people who'll help lead it
Bonus Points
- Experience with procurement, ERP or B2B commerce systems (Coupa, SAP Ariba, Oracle, NetSuite)
- Event-driven systems and data pipelines (Kafka, change data capture, Postgres at scale)
- Experience at a startup or growth-stage company where you owned outcomes, not just tickets
- Work that shows how you build: open source, a side project, or a write-up of how AI changed the way you work
About this role
Fairmarkit is building an autonomous sourcing platform that uses AI and automation to help procurement teams buy and sell more competitively. As a Senior Full-Stack Engineer here, you'd own the backend architecture that powers their core product—the domain models, APIs, event-driven services, and integrations that connect Fairmarkit to customer ERPs and procurement systems. The work is genuinely full-stack but backend-heavy; you'll design features end to end with product, design, and frontend teams, but your judgment and depth will show most in how you structure data, define service boundaries, and handle the integrations that move purchase data between systems.
This role suits someone with real depth in backend systems who also ships across the stack. You'll need strong fundamentals in system design, type safety, and at least one statically typed language (Java, C#, Go, Kotlin, Scala, or Rust) alongside TypeScript and Python. Critically, you'll work with AI coding agents daily and have the discipline to review and own what they produce—this isn't about replacing your judgment, but about raising your standards elsewhere: problem framing, system design, code review, and production ownership. You'll move across product areas as priorities shift, ramp fast into unfamiliar domains like procurement workflows or ERP integrations, and document your decisions in writing so teammates can build on them asynchronously.
The role is in-office in Warsaw and full-time. Experience with procurement systems, event-driven architectures, or growth-stage startups is a bonus. If you're someone who learns domains quickly, cares about engineering rigor, and can hold AI-generated code to the same standard as your own, this is worth a close look.
How this employer is doing
solid
- Expanding
In the news
Conduent Expands Finance and Procurement Capabilities with Fairmarkit's AI-Powered Technologies including GenAI, www.news.conduent.com
This role's local market on JobMinglr
Pay for this role
The employer didn't post a pay range for this role. That usually means pay is set in negotiation, which favors whoever arrives with numbers. Check ranges on comparable Senior Full-Stack Engineer (Backend Leaning) postings in Warsaw, and analyze any offer before you accept it.
Before you apply, worth reading
How JobMinglr reads this job
Every listing here is scored against your profile before you apply: skills overlap, experience level, location and work arrangement, each weighted and explained. You see the score and the reasons, not just a list. How the matching works.