Software Development Engineer in Test (SDET)

About Nexus

Nexus is the engine for verifiable finance — a blockchain designed to natively embed the world’s financial system into one compounding system. Built to support every major financial market on a single global exchange, Nexus unifies infrastructure that has historically been fragmented across chains and intermediaries.

Headquartered in San Francisco with a growing presence in Buenos Aires, Nexus is proud to be a cross-continental team of engineers, cryptographers, and market builders. We’re investing deeply in the Latin American ecosystem — and always looking for world-class talent to join us.

Nexus is backed by leading investors, including Pantera, Lightspeed, Dragonfly, Faction, Blockchain Builders Fund, Alliance, and SVA, and works with more than 100 partners across the global finance and blockchain stack.

Location: Remote (Argentina)

Type: Contract

Duration: 12 months with potential for extension

The Role

We’re expanding our engineering team in Latin America to strengthen quality and reliability across Nexus’s Layer 1 and its native DEX. As a Software Development Engineer in Test (SDET), you’ll help build and maintain the automated testing infrastructure that ensures our trading, settlement, and blockchain systems are secure, performant, and production-ready.

You’ll collaborate with backend, protocol, and frontend engineers in San Francisco while contributing remotely from Argentina, helping ship high-quality financial infrastructure at scale.

What You’ll Do

• Develop and maintain automated test suites for backend services written in Node.js and Rust
• Build integration and end-to-end tests covering trading flows, settlement logic, and on-chain verification
• Design test cases for APIs, data pipelines, and distributed system components
• Assist in implementing CI/CD pipelines to automate testing and deployment validation
• Write performance and regression tests to ensure reliability under high-load conditions
• Debug issues across services, reproduce bugs, and collaborate with engineers to resolve them
• Contribute to improving test coverage, observability, and quality standards across the codebase.

What We’re Looking For

• 1–2 years of experience in software development or QA automation (internships or academic projects count)
• Experience writing automated tests using JavaScript/TypeScript, Rust, or similar languages
• Familiarity with testing frameworks (e.g., Jest, Mocha, Playwright, Cypress, or similar)
• Basic understanding of APIs, databases, and backend systems
• Strong problem-solving skills and attention to detail
• Excellent communication skills in Business English (spoken & written)
• Eagerness to learn about distributed systems, financial infrastructure, and blockchain technology.

Bonus Points For

• Experience testing APIs or backend services.
• Exposure to CI/CD tools (GitHub Actions, Docker, etc.)
• Familiarity with blockchain fundamentals or smart contracts
• Understanding of performance testing concepts and tools
• Experience working in fast-paced startup environments

Why Join Us

• Build the backend systems powering the Layer 1 for Verifiable Finance.
• Collaborate with experts across blockchain, AI, and financial infrastructure.
• Shape the foundation for a verifiable, transparent, global trading system.
• Thrive in a fast-moving, high-impact engineering environment.

Key skills/competency

• Automated Testing
• Quality Assurance
• CI/CD
• Node.js
• Rust
• JavaScript
• TypeScript
• Blockchain
• Distributed Systems
• API Testing