Full-stack Engineer (Junior) — Platform, Testing & Tooling

*Do Not Reach Out on Linkedin, All Hiring Will Be Done via Wellfound

How Zabili is structured

Zabili is the prediction market platform built and operated by Degenerate. It runs on two arms off one platform. The consumer arm (B2C) is our own product, where users trade directly with us. The partner arm (B2B) licenses that same engine to betting and gaming operators, who run our markets inside their platforms, under their brand, with their wallet. Every role on this team serves both.

Working pattern

We work remotely on GMT+3 core hours, so your day overlaps with the rest of the team. Markets resolve when events happen, and events happen at weekends — sport especially. Expect some weekend cover on a rota, and occasional out-of-hours work around launches and partner go-lives. It is shared across the team, it is planned in advance rather than sprung on you, and it is not a euphemism for working every Saturday.

Why this role exists

We handle real money on our own platform and on behalf of partner operators, so a manual test pass is not a control. This role builds the automated evidence that both arms are correct — and in doing so, learns the entire system faster than anyone else on the team, because you cannot test what you do not understand.

What you'll own — consumer platform (B2C)

• The smoke suite that runs on every pull request, and the end-to-end suite behind it
• Automating the core ledger invariants so violations fail the build and raise an alert
• Test environments and seed data covering markets and users in every state
• CI/CD pipelines and the release checklist
• Internal tooling and scripts that make the rest of the team faster
• Observability: dashboards, logging and alerting that make problems visible early
• Reproducing and documenting bugs so they can actually be fixed

What you'll own — partner product (B2B)

• Tenant isolation testing — proving that one operator can never read, affect or settle against another operator’s data. This is the single most important test class on the partner arm.
• Contract tests against the partner API, so a change on our side that would break a live operator fails in CI first
• Maintaining partner sandbox environments and the seed data operators integrate against
• Testing the seamless wallet round trip under failure: partner timeout, partner rejection, duplicate callback, settlement arriving twice
• Assembling the technical evidence packs used in operator and regulator certification

Must have

• 1–3 years professional experience, or a portfolio of substantial projects you can walk us through in detail
• Strong scripting ability in Python, TypeScript or similar — you write your own tools rather than waiting for one
• Comfortable in a terminal, with Git and with CI systems
• Genuine curiosity about how systems break, not just how they work
• The discipline to write things down so the next person does not have to rediscover them
• Willingness to be the person who says "not yet" to a release

Nice to have

• Playwright, Cypress or any end-to-end testing framework
• API contract testing tooling
• Docker and any infrastructure-as-code exposure
• Load or performance testing experience
• Any exposure to payments, exchange or other correctness-critical systems

How this role is supervised

You will be paired closely with the senior engineers while you learn the ledger and payment paths, and your work will be reviewed thoroughly. Over the quarter this role moves from supervised to genuinely autonomous — the release gate becomes yours to hold, and you will be backed when you hold it.