We are supporting an APAC-focused technology company building a non-custodial, protocol-level payment infrastructure that enables seamless on-chain settlement for API-based services. The project sits at the intersection of Web3 payments, cryptographic verification, and high-reliability backend systems, with a strong emphasis on security, low latency, and production-grade operations.
This is a greenfield build where senior engineers will help define architecture, security models, and operational standards from day one.
As a Senior Software Engineer, you will take ownership of core backend services that verify cryptographically signed payment requests and coordinate on-chain settlement across multiple blockchain networks. You will work closely with security, compliance, and product stakeholders, and play a key role in shaping system design, reliability practices, and developer experience.
Responsibilities
- Design and implement high-performance backend APIs for payment verification and settlement
- Build cryptographic verification logic (signature validation, replay protection, idempotency)
- Integrate with blockchain RPC providers and design confirmation, retry, and failover strategies
- Architect secure key-management solutions (KMS/HSM), audit logging, and least-privilege access
- Develop chain adapters for EVM and non-EVM networks, starting with stablecoin transfers
- Own production readiness: SLOs, monitoring, alerting, and incident response workflows
- Write technical documentation, threat models, and operational runbooks
- Mentor junior engineers and contribute to engineering standards and best practices
Qualifications
- 5–8+ years of backend engineering experience, ideally in TypeScript/Node and/or Rust
- Strong understanding of cryptographic signatures, structured payloads, and API security
- Hands-on experience with EVM transaction lifecycle (nonce, gas, finality) and/or Solana
- Proven track record building production-grade distributed systems
- Experience with CI/CD, containerised deployments, and observability tooling
- Excellent written communication skills (design docs, threat models, runbooks)
Strongly Preferred
- Experience with payment or settlement systems (idempotency, retries, reconciliation)
- Familiarity with stablecoin transfer patterns (e.g. USDC on EVM chains)
- Background in non-custodial architectures or security-sensitive systems
- Exposure to protocol-level payment flows, API monetisation, or metered billing
