Senior Backend Engineer — DeFi API & Serverless Scale

Usual; Paris; Sur place; EUR 75 000 - 115 000; Plein temps

Avantages offerts par ce poste

Competitive salary

Token options

Résumé du poste

Usual is expanding its backend team to scale the DeFi protocol and dApp infrastructure. You’ll own backend services, APIs, and off-chain logic that power data, yields, rewards, and integrations in a fast-paced startup setting.

Join a small, motivated team focusing on reliable, scalable systems. The role emphasizes API quality, collaboration with frontend and product teams, and a backend-first approach.

Qualifications

• 3+ years experience as a backend engineer, ideally in a startup or high-growth environment.
• Proficiency in NestJS / TypeScript and understanding of clean API architecture.
• Hands-on experience with serverless environments (Cloud Run, AWS Lambda, etc).
• Familiarity with Viem, The Graph, and interacting with EVM-based blockchains.
• A strong product mindset: you understand how backend impacts UX, and you care about building smooth user experiences.

Responsabilités

• Architect and develop backend services using NestJS and serverless (e.g. GCP Cloud Run, AWS Lambda).
• Design, build, and maintain REST APIs that expose data for internal and external use (frontend, integrations, dashboards).
• Integrate with smart contracts on Ethereum and L2s via Viem and The Graph.
• Implement off-chain business logic and computation to support key protocol features (yield, rewards, simulations, etc).
• Optimize performance, reliability, and scalability of the system as we grow.
• Collaborate with the rest of the tech team (frontend, smart contracts, product) to scope and deliver product features.
• Propose improvements in architecture, stack, and dev processes.

Connaissances

NestJS/TypeScript

Backend development

API design

Serverless

DeFi/blockchain knowledge

Outils

Viem

The Graph

Ethereum / EVM

Description du poste

Usual is expanding its backend team to scale the DeFi protocol and dApp infrastructure. You’ll own backend services, APIs, and off-chain logic that power data, yields, rewards, and integrations in a fast-paced startup setting.

Join a small, motivated team focusing on reliable, scalable systems. The role emphasizes API quality, collaboration with frontend and product teams, and a backend-first approach.