Backend Engineer
at 3F Labs.
3F is building the leverage layer for tokenized real-world assets: a Morpho-based vault protocol for leveraged exposure to tokenized CLOs, private credit, and fixed income through a single transaction.
We raised $4M from Maven 11, F-Prime, GSR, and Gate Ventures, and we are live on Ethereum mainnet with real capital. The team is six people.
Apply nowThe Role
Ownership
Backend systems that coordinate leveraged positions across on-chain and off-chain settlement, with security as a default. The orchestration layer is where you would spend most of your time: coordinating bridge financing, Morpho collateral, stablecoin borrowing, transaction submission, and portfolio state under adversarial conditions.
- Design and build APIs for position management, auction mechanics, and portfolio tracking.
- Develop orchestration services for multi-step settlement workflows across bridge financing, Morpho collateral, and stablecoin borrowing.
- Integrate with on-chain protocols such as Morpho, Centrifuge, and Pareto/Idle: read state, submit transactions, and handle epoch-based settlement cycles.
- Extend and maintain cloud infrastructure on GCP/GKE using Terraform.
- Contribute to reliability and security: alerting, observability, database hardening, least-privilege access controls, and CI/CD pipelines.
- Own the security posture around audit logging, secret management, API boundaries, transaction-signing validation, and smart contract interaction safeguards.
- Review code with an adversarial lens, coordinate with auditors, and help triage bug bounty submissions as the protocol's attack surface grows.
Stack
| Layer | Technology |
|---|---|
| Core services | Rust (auction engine, orchestrator) |
| API layer | TypeScript / Node.js |
| Smart contracts | Solidity (Morpho integrations, facilitators) |
| Database | PostgreSQL (Cloud SQL) |
| Infrastructure | GCP, GKE, Terraform |
| CI/CD | GitHub Actions, GKE |
What We're Looking For
How to read this role
You do not need every part of the stack on day one. The core signal is backend judgment: owning production systems, reasoning carefully about financial state, and learning unfamiliar protocols without hand-waving. DeFi helps, but strong engineers from fintech, infra, trading, payments, or security-heavy systems should feel welcome.
Core signals
- Backend systems in production: APIs, data models, migrations, deploys, and operational tradeoffs.
- Strong Rust or TypeScript. Strength in one and willingness to learn the other is enough.
- Careful reasoning about financial state, permissions, signing flows, consistency, and failure modes.
- Production ownership mindset: tests, observability, clear rollback paths, and pragmatic release discipline.
Helpful background
- Fintech, trading, payments, DeFi, crypto, or security-heavy infrastructure.
- Kubernetes, Terraform, GCP/GKE, or similar production platform work.
- Morpho, Aave, or other lending protocol exposure.
- Threat modeling, audit workflows, penetration testing, or bug bounty triage.
Working at 3F
How we work
- Small team, high autonomy. Everyone ships to production, without layers of approval.
- Weekly dev syncs, with async-first communication otherwise.
- You will work across the full backend surface: API endpoints, settlement orchestration, transaction flows, infrastructure provisioning, observability, and incident response.
- Specialization happens naturally, not by assignment.
Production ownership
Because the team is small and the system handles real capital, this role includes production ownership and incident response. The goal is to make systems boring through observability, runbooks, testing, least-privilege access, and careful release process.
Build the future
of onchain credit.
Send a CV or relevant profile and a brief note on your background and interest in the role.
Tell us a little about yourself.
Application received.
Thanks for your interest in 3F. We will review your application and be in touch.