Senior On-Chain Backend Engineer

Fireblocks Inc.; Greater London; Hybrid; GBP 120,000 - 180,000; Full time

Benefits offered by this job

Competitive compensation

Meaningful equity

Ownership culture

Job summary

Fireblocks Inc. is seeking an experienced Backend/Full Stack Engineer to design and build scalable backend services for high-volume on-chain transactions.

You will own end-to-end components and APIs, lead integrations across DeFi protocols and blockchain nodes, and push for performance, reliability, and security across multi-chain ecosystems. You’ll collaborate with product, protocol research, and platform teams to deliver features at scale, contributing to a mission-critical infrastructure

Qualifications

• Experience in backend engineering for large-scale systems.
• Strong understanding of blockchain transaction lifecycles and security.
• Hands-on with multi-chain ecosystems (EVM and non-EVM).

Responsibilities

• Design and build robust backend services for high-volume on-chain transactions.
• Own end-to-end backend components and APIs from design to production.
• Lead integrations with DeFi protocols and on-chain data sources.
• Research emerging blockchain technologies to keep Fireblocks cutting edge.
• Optimize production systems for performance, reliability, and security.
• Collaborate with product, protocol research, and platform engineering teams.
• Drive features from inception to delivery at scale.

Skills

Backend engineer

System design

Blockchain & Web3

Security principles

CI/CD

Education

Bachelor's degree or equivalent

Tools

Node.js

TypeScript

ethers.js

viem

web3.js

Solana web3.js

Job description

Fireblocks Inc. is seeking an experienced Backend/Full Stack Engineer to design and build scalable backend services for high-volume on-chain transactions.

You will own end-to-end components and APIs, lead integrations across DeFi protocols and blockchain nodes, and push for performance, reliability, and security across multi-chain ecosystems. You’ll collaborate with product, protocol research, and platform teams to deliver features at scale, contributing to a mission-critical infrastructure