Senior Backend Engineer

ABOUT US

Xsolla is a global commerce company with robust tools and services to help developers solve the inherent challenges of the video game industry. From indie to AAA, companies partner with Xsolla to help them fund, distribute, market, and monetize their games. Grounded in the belief in the future of video games, Xsolla is resolute in the mission to bring opportunities together, and continually make new resources available to creators. Headquartered and incorporated in Los Angeles, California, Xsolla operates as the merchant of record and has helped over 1,500+ game developers to reach more players and grow their businesses around the world. With more paths to profits and ways to win, developers have all the things needed to enjoy the game.
For more information, visit xsolla.com.

 
Web3 backend experience: blockchain integration, wallet infrastructure, account abstraction


High-load systems


Cloud platforms (GCP, AWS or Azure) and infrastructure-as-code


NoSQL databases (MongoDB or similar)


Domain experience in gaming, e-commerce, fintech or payments



HOW WE WORK



Decisions in writing. Significant technical decisions are written up as an RFC or ADR that lays out the options and trade-offs. We discuss the document, not a blank whiteboard.


AI is part of everyday engineering. We use AI coding tools for development and review, and we treat configuring them for a codebase as real engineering work.



HOW WE HIRE



Intro call. Your background, your motivation and the role.


Technical interview. Built directly on the What you will own and Required sections above. We won't ask about anything this posting doesn't promise.


Bar raiser. An engineer from outside the hiring team checks that you raise the overall engineering bar.



THE TEAM

You will work alongside product managers, designers, backend and frontend engineers, QA and DevOps.

THE ROLE

We are hiring a Senior Backend Engineer for two platform products:


Xsolla ID is the identity and authentication platform behind sign-in, account management and SSO across Xsolla products.


Xsolla ZK is Web3 wallet infrastructure: smart wallets and account abstraction on a zkSync-based L2.


Both products sit on users' most sensitive flows, logging in and signing transactions, and other Xsolla teams build on top of them.

WHAT YOU WILL OWN



The backend services of your product area end to end: design, implementation, release and production operation, including on-call


Architecture across services: service boundaries, integration contracts and data ownership. You make these decisions and justify them in writing


Reliability and security of critical flows: SLOs, failure handling, protection of user data and credentials


Service performance and cost under load





WHAT YOU WILL DO



Design and build services and APIs (REST, gRPC) for authentication, account management and wallet operations


Define service boundaries and integration contracts with other Xsolla teams


Design data models and storage; optimize schemas and queries


Build event-driven and asynchronous workflows


Own observability: metrics, logs, tracing and alerting, and act on what production tells you


Take part in on-call, incident response and post-mortems


Improve the engineering environment: CI/CD, infrastructure-as-code, testing


Review code


Set up and maintain AI tooling in the repositories (Claude Code, Codex, Cursor: rules, context, harness) so the team uses it effectively
Language and platform


5+ years of commercial backend development


Go: idiomatic code, concurrency (goroutines, channels, context and cancellation), memory and performance profiling (pprof)


Data


Relational databases (PostgreSQL, MySQL): schema design, indexes, query plans, transactions and isolation levels, safe migrations


Caching (Redis): when to cache, invalidation, consistency trade-offs


Distributed systems


Service architecture and distributed-systems trade-offs: consistency, availability, idempotency, retries, failure modes


Asynchronous messaging and event-driven design (Kafka, RabbitMQ or NATS): delivery guarantees, ordering, reprocessing


APIs


Designing REST and gRPC APIs: versioning, backward compatibility, contract documentation (OpenAPI / Swagger, Protobuf)


Security and identity


Application security: common vulnerability classes (OWASP Top 10), secrets management, safe handling of user data


OAuth 2.0 / OIDC from the server side: flows, tokens, sessions


Operations


Containers and orchestration (Docker, Kubernetes) at the level of deploying and debugging your own services


Observability (we use Datadog; experience with Prometheus, Grafana, ELK / Graylog or OpenTelemetry also counts): metrics, logs, tracing and alerting; diagnosing incidents in production


Engineering practices


Testing: unit, integration, contract


Git, CI/CD (GitLab CI or similar)


AI-assisted engineering


Daily hands-on use of AI coding tools (Claude Code, Codex, Cursor) for development and review, including configuring them for a repository


English




Reading technical documentation in English