Sr Backend Engineer (Blockchain, Crypto Exchange, Java)

As a Sr Backend Engineer at TON, you own core exchange modules end to end: design, code, tests, deployment, and production behaviour. You work directly with the founder to build the technical foundation of a crypto exchange, with full control over tech stack and architecture.

What you'll do

• Own a core exchange module end to end, from design through code, tests, deployment, and production operations
• Build wallet infrastructure and on-chain deposit and withdrawal flows, including idempotent retries, network failure handling, safe recovery, and balance reconciliation
• Bring design, estimates, dependencies, and technical risks for your module into the shared roadmap, and drive build-versus-integrate evaluations for third-party services, SDKs, and node infrastructure in your area
• Settle REST and WebSocket contracts with frontend, including real-time market data
• Ship to production standards: automated tests, CI/CD, monitoring and alerting, audit logs, access control, and review for anything touching real assets
• Take operational ownership of what you build: lead triage on incidents in your modules, run the post-mortem, and land the fix that prevents repeat incidents

What you bring

• 5+ years of backend engineering with production ownership of at least one system that moves real money or real assets (exchange ledger, custody and wallet, payment settlement, trading backend, or equivalent)
• Expertise in correctness under concurrency: database transactions, idempotency, monetary precision and rounding, reconciliation, and clean recovery from partial failure
• Strong proficiency in Go, Java, or Rust, or deep Node.js and TypeScript experience with proven handling of concurrency and load, plus SQL, Redis, a message queue, and WebSocket
• Production operations experience: you have deployed, monitored, and diagnosed systems under pressure
• Solid grasp of access control, separation of duties, secure credential storage, and transaction signing
• Ability to read English technical documentation and explain architecture, risk, and progress clearly

Nice to have

• Direct experience inside a live CEX (order matching, ledger, or wallet at any scale)
• Hot and cold wallet architecture or institutional custody integration
• TON, Jetton, or Telegram Mini App (TMA) development
• Liquidity provider or market maker integrations
• Load testing, disaster recovery drills, or security audit participation

What we offer

• Salary of 45-60M with 13th-month salary and project bonuses
• Work directly with the founder to build the technical foundation and shape the product from the earliest stage
• Scope of technical decision-making on architecture, technology, and development standards agreed together with the founder
• Supporting resources and on-call rotation arrangement discussed and clearly agreed before you accept the offer
• Free food and drinks at the pantry
• Social insurance and annual leave according to regulations