Backend Developer – High-Performance CEX (Elysia.js / Express, Bun.js, Rust, Go)

About the Role:

• We are building a next-gen centralized crypto exchange (CEX) and are looking for Backend Developers

  on-site role (Delhi/NCR)

  who can design and implement ultra-low latency APIs, secure trading infrastructure, and scalable microservices.
• You’ll be working with a modern backend stack — including Elysia.js or Express.js (running on Bun.js or Node.js), with key components built in

  Rust and Golang

  to ensure optimal performance, concurrency, and memory safety. You'll also collaborate with frontend, devops, and security teams to build reliable systems that can scale globally.

Responsibilities:

• Design, develop, and maintain backend services and APIs for a real-time crypto trading platform.
• Use Elysia.js (or Express) with Bun.js or Node.js for fast, modern web APIs.
• Build high-performance modules and trading logic using Rust and/or Go, where performance is critical.
• Implement core services such as order matching, wallets, account management, KYC/AML, and market data feeds.
• Write clean, well-structured, and testable code with proper documentation.
• Optimize system performance, response time, and scalability.
• Collaborate with security teams to ensure systems are hardened against attacks and vulnerabilities.
• Work with databases, caching layers, and messaging queues (e.g., Redis, PostgreSQL, Kafka/NATS).
• Implement monitoring, observability, and logging for mission-critical backend services.

Tech Stack:

• Languages:

  TypeScript (Bun.js or Node.js), Rust, Go (Golang)

• Frameworks:

  Elysia.js (preferred), Express.js

• Runtime:

  Bun.js (preferred), Node.js

• Databases:

  PostgreSQL, Redis, ClickHouse, MongoDB (as needed)

• Queues/Streams:

  Kafka, NATS, or RabbitMQ

• Auth/Security: JWT, OAuth2, 2FA, WebAuthn, encryption best practices
• Infrastructure:

  Docker, CI/CD, GitHub Actions, AWS/GCP

Requirements:

• 3+ years of backend experience

  building APIs, microservices, or real-time systems

• Strong experience with TypeScript using Elysia.js or Express.js

• Familiarity with Bun.js or willingness to transition from Node.js to Bun
• Production-level experience in Rust or Golang (preferably both)
• Solid understanding of secure API design, cryptographic primitives, and rate-limiting
• Experience working with PostgreSQL, Redis, and event-driven architectures
• Ability to write clean, efficient, and well-documented code
• Good understanding of distributed systems, performance optimization, and error handling

Bonus Points:

• Built or contributed to crypto exchanges, trading engines, or blockchain infrastructure
• Experience with matching engines, market makers, or order book implementations
• Familiarity with Web3 concepts and crypto wallet integrations

• Prior work with high-frequency trading systems, FIX protocol, or low-latency systems

• Familiarity with observability tools (Prometheus, Grafana, Sentry, etc.)