Senior Back-End Engineer (Setapp)

Jira ticket MacPaw is building the next generation of its Setapp Marketplace —a platform where developers distribute Mac, iOS, and Web applications to a wide audience around the world. We're looking for a Senior Backend Engineer (Golang) to build the Ledger and Promotion domains from the ground up. On the Ledger side that means commission terms, revenue splits, and the contracts between developers, sellers, and the platform. On the Promotion side it means coupons, promo codes, redeem codes, and gift cards, and the acquisition and gifting models built on them. You’ll work with complex business logic, third-party integrations, and existing systems, collaborating closely with product and engineering teams. We’re looking for someone curious, proactive, and responsible who enjoys learning, taking ownership, and improving solutions. Our back-end stack: Go, Temporal, PHP 8.0+ (Symfony Components, Doctrine ORM); PostgreSQL, Redis, RabbitMQ; PHPUnit; Cloud-Native: AWS, GCP, K8s, Docker. In this role, you will: Own the solution design end to end: take an ambiguous business task, propose how the system should evolve, defend it in a peer design review, and then build it Model new commercial concepts for Ledger and Promotion capabilities so they stay consistent with the rest of the platform's domain model Work closely with PMs, EMs, and cross-functional teams to clarify requirements, handle edge cases, and find the most effective implementation paths Gradually refactor and migrate parts of the monolith into independent, high-performance services Take full responsibility for code quality by writing Unit/Functional tests and actively participating in E2E testing (our engineers drive quality alongside QA) Write clean, efficient, and scalable code using Go and PHP (Symfony) Skills you’ll need to bring: 5+ years building production services in Golang Solution and system design as a primary skill DDD in practice: bounded contexts, aggregates, when to split a service, and why a shared database isn't a boundary Confident work with PostgreSQL/relational databases: schema design, complex SQL queries, migrations, and performance optimization (indexes, profiling) Experience with RabbitMQ (or similar message queues): pub/sub and work queue patterns, producers/consumers, basic configuration concepts API design: resource modeling, versioning, idempotency keys, error contracts, backward compatibility for public APIs Go depth: concurrency and graceful shutdown, detecting data races and goroutine leaks, pprof, table-driven testing Docker, plus working knowledge of Kubernetes objects and probes CI/CD, feature flags, trunk-based development, safe migrations Observability: logs, metrics, traces, SLI/SLO/SLA Awareness of secure coding principles (OWASP) At least an intermediate English and fluent Ukrainian As a plus: Workflow orchestration (Temporal or similar) for compensation and retries in long-running money flows PHP (Symfony), since parts of the current system still live there Terraform, Redis, MongoDB