Context
A Python 3.13 microservices platform (uv workspace) behind a charity-driven lottery
product operating with real money in production (live in LatAm). The wallet/ledger,
payments, and settlement code is there — double-entry, idempotent, reconciled. We're a
startup, and as we grow we're hiring a senior to own and evolve the money core.
What you'll own
• The wallet / ledger — double-entry accounting, idempotency, reconciliation, combined
bank + cash flows, settlement requests.
• Payment integrations (incl. a local QR provider) and the payment/settlement services;
the in-flight wallet extraction out of the API.
• PostgreSQL design with transactional rigor — isolation, locking, indexing, migrations
(Alembic).
• FastAPI services in the uv-workspace monorepo with typed RPC contracts; the Django
admin/operational layer where needed.
• Auth & security — JWT, password hashing, 2FA/OTP.
• Reliability — transactional-outbox patterns, background workers, observability
(Prometheus/Grafana), pytest coverage on money paths.
• Partnering with compliance on KYC/AML and multi-jurisdiction requirements (LatAm live,
Cyprus incorporating).
• Taking full ownership of the ledger, then raising the bar on correctness and
reconciliation tooling.
Must-have
• Expert Python 3.11+; async/await; fluent type hints.
• FastAPI in production (routers, dependencies, middleware, background tasks).
• SQLAlchemy 2.0 + SQLModel (async) and asyncpg.
• PostgreSQL depth — schema design, indexing, transactions/isolation, migrations.
• Pydantic v2.
• Financial-systems experience: double-entry ledgers, idempotency,
reconciliation, payments — this is the core requirement, not a bonus.
• Auth flows (JWT, hashing); security-minded.
• Docker; Redis/Valkey.
• Languages: professional working English required; Russian a strong plus.
Senior Backend Engineer — Fintech / Payments 2
Nice-to-have
• Django (the admin service).
• Payments / PSP integrations; local payment rails / QR; settlement & chargeback flows.
• iGaming or regulated-fintech production; audit/compliance (KYC/AML).
• uv, Ruff, Pyright; microservices + RPC; transactional outbox.
• Observability (Prometheus); aioboto3/S3; message-driven patterns.
First 90 days
Full ownership of the wallet/payments/settlement code; a reconciliation or idempotency
improvement shipped; test coverage raised on money-mutating paths.
