Backend Engineer (Contract - LATAM)

About Nexus

Nexus is building the AI gateway for modern companies — one platform that gives teams access to the world's leading AI models while keeping costs predictable, security under control, and workflows connected.

Companies can use Nexus to access models like GPT, Claude, Gemini, and many others through a unified platform. Our infrastructure helps organizations choose the right model for each task, manage usage and budgets, enforce access policies, and integrate AI into the tools their teams already use.

Headquartered in San Francisco with a growing presence in Latam, Nexus is a cross-continental team building the infrastructure that makes AI more accessible, efficient, and manageable at scale.

We're investing deeply in the Latin American engineering ecosystem and looking for exceptional talent to help us build the next generation of AI infrastructure.

Nexus is backed by leading investors, including Pantera, Lightspeed, Dragonfly, Faction, Blockchain Builders Fund, Alliance, and SVA.

Location: Remote

Type: Contract

Duration: 12 months with potential for extension

The Role

We're expanding our backend engineering team in Latin America to build the infrastructure powering Nexus's AI gateway.

We're looking for talented Backend Engineers who enjoy solving complex technical challenges, building reliable systems, and working on products used at scale.

You'll help develop the core services behind our platform, from AI model integrations and intelligent request routing to API infrastructure, usage tracking, and enterprise controls.

This role combines backend engineering, distributed systems, and emerging AI technologies. You'll work on systems where performance, reliability, and scalability matter, helping companies access and manage multiple AI models through a single platform.

You'll collaborate closely with engineering and product teams in San Francisco while contributing remotely from Latin America.

What You'll Do

• Design, develop, and maintain scalable backend services powering Nexus's AI gateway.
• Build APIs and integrations with leading AI providers, including OpenAI, Anthropic, Google, and open-source models.
• Develop infrastructure for intelligent model routing, request processing, and workload orchestration.
• Build systems for tracking AI usage, managing costs, enforcing budgets, and controlling access to different models.
• Design and maintain integrations with enterprise applications, developer tools, and third-party services.
• Improve backend performance, reliability, scalability, and observability.
• Write clean, efficient, well-tested, production-grade code.
• Contribute to system architecture, technical decisions, and engineering best practices.
• Collaborate with engineers across backend, frontend, infrastructure, and product teams to ship new features and improve existing systems.

What We're Looking For

• Strong experience developing backend systems in production environments.
• Solid computer science fundamentals, including data structures, algorithms, and software design.
• Strong understanding of backend architecture, API design, and distributed systems.
• Experience with backend technologies such as Node.js, TypeScript, Go, Rust, C++, or similar languages.
• Experience working with relational databases such as PostgreSQL or similar.
• Good understanding of concurrency, asynchronous programming, and performance optimization.
• Experience designing, building, and maintaining reliable and scalable services.
• Strong problem-solving skills and the ability to work through complex technical challenges.
• A track record of shipping high-quality software and taking ownership of engineering projects.
• Ability to collaborate effectively in a fast-paced, distributed engineering environment.
• Excellent communication skills in Business English, both spoken and written.

Levels We're Hiring

• Junior 1–3 years - Solid foundations, eagerness to grow, guided ownership
• Principal 8+ years - System design leadership, cross-team impact, mentorship, leading 5 Jr engineers in parallel and teams of at least 10 engineers

Bonus Points For

• Experience building AI-powered applications, LLM integrations, or AI infrastructure.
• Familiarity with APIs from OpenAI, Anthropic, Google Gemini, or other AI providers.
• Experience with API gateways, request routing, load balancing, or rate limiting.
• Experience building high-throughput, low-latency, or large-scale distributed systems.
• Familiarity with AI agents, workflow orchestration, or developer tools.

Why Join Us

• Build the future of enterprise AI: Help create the infrastructure that allows companies to access and manage the world's leading AI models through one unified platform.
• Solve meaningful technical challenges: Work on distributed systems, intelligent model routing, scalable APIs, and high-performance backend infrastructure.
• Work with emerging AI technologies: Contribute to products that connect AI models, applications, and enterprise workflows.
• Have a direct impact: Help shape the architecture and evolution of a growing platform where engineering decisions matter.
• Collaborate with an international team: Work alongside talented engineers and product builders across San Francisco and Latin America.
• Grow in a fast-moving environment: Take ownership, solve challenging problems, and contribute to a product operating at the intersection of AI and software infrastructure.