Senior/Lead Backend Developer
Selection Lab
40 uur
Amsterdam
Senior
€5.500 – €7.500

Functieomschrijving

Design code architecture for reliability, performance, and security. Ship APIs/features that integrate cleanly with our Svelte frontend and external systems; use AI where it multiplies speed and quality.

More examples:

  • Deliver/refactor a core API/feature with clear planning & docs
  • Improve perf/stability (caching, queues, requests)
  • Set habits: code quality, observability, communication, optimisation

Functie-eisen

Backend: Python (Flask, FastAPI, WebSockets, Celery)
Data/infra: Postgres, Redis, Docker, Heroku, AWS (S3, Cloudfront, Dynamodb, etc.)
Frontend: TypeScript, Svelte
(Dev) Tools: GitHub (CI/CD), typed code, tests (a lot), pytest, Ruff, Linear, Notion, Slack
(Dev) AI Tools: Copilot, Claude code, Langfuse

That said, we're always looking for ways to improve and optimize! Not just ourselves, but also our tooling.

What you'll bring

  • Scale‑up ambition: bias for action, clear planning & communication, and end‑to‑end ownership.
  • T‑shaped: primarily backend, but you can jump into our TypeScript/Svelte frontend to unblock teammates, know your way around infra, etc.
  • Team-first: be able to help and learn something to others, review PRs, elevate (best) engineering practices and vision across a team
  • Ability to challenge and refine architectural choices together with the CTO.
  • 5–10 years backend experience in an ambitious environment. Preferably in Python and/or a high-level language (Go, Elixir, Rust, etc.).
  • Strong API/code design, automated testing, and observability habits
  • Security mindset & data privacy awareness

Nice to have: experience with: Flask/FastAPI, background workers/queues, Postgres, Redis, perf profiling, analytics, internationalization

Aanbod

  • Salary €5,500–€7,500 (depending on experience) + 8% holiday pay
  • Options to Stock Appreciation Rights (SAR)
  • Office in central Amsterdam
  • MacBook Pro
  • Personal budget to improve your workplace to your likings
  • Additional budget for books, coaching, or your way to learn and grow
  • Team lunches, regular team outings, boot camps, champagne.
  • Expense reimbursement for opening a pension account at Brand New Day
  • 25 vacation days + 2 extra public holidays
  • CO₂ compensation via tree‑planting initiatives

Over het bedrijf

We’re a product-first, fast-scaling HR tech company "Automating the selection process from careers page to first live interview".
Our goal: make hiring radically more efficient and objective. We ship fast, learn from real usage, and iterate fast.

  • Fast-growing SaaS → impact measured in days, not quarters (or worse)
  • A great Dev team (7) → real ownership and a direct line to decisions
  • Data‑informed & user‑obsessed → ship → measure → iterate
  • High bar, low ego → crisp feedback, privacy‑by‑default

This is the work environment: an outcome‑driven team. High bar, low ego. We share knowledge proactively, give crisp feedback, and make decisions fast. Continuous demos, lightweight RFCs, and blameless post‑mortems keep us learning. We work office-first from our lovely office in central Amsterdam. We deliver extraordinary results. We learn fast, together. We show we care.

 

A Typical Day at The Selection Lab

  • Start by syncing in Linear and checking open PRs.
  • Deep work on APIs, performance, or robustness.
  • Lunch with the team (Friday roti is a tradition).
  • Reviews & pairing to keep code clean and quality high.
  • In-depth session to sketch (long term) architecture for a new feature together with the CTO
  • More focus time to push a feature, explore a new approach or help a teammate out.
  • Growth: 1:1s, learning, or short tech spikes.
  • Wrap up your way (boot camp, drink, or one last PR).

Informeren en solliciteren

We'd love to hear from you! Also if you feel you don't meet 100% of the criteria but are very enthusiastic about the role.

Our aim is to ensure everyone has a fair and bias-free chance. That’s why we’ll ask a variety of questions in the most objective manner (rather than inviting you for a coffee right away - although we do love coffee ☕️).

Please take a moment to answer the questions in our application form. This will help us both to determine if there could be a good fit between us.

If your answers indicate a great fit, we'll definitely get in touch with you!

Interesse?

Solliciteer nu!

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