Member of Technical Staff (Software Engineer, Backend API)

United States Digital Space LLC; Greater London; On-site; GBP 90,000 - 130,000; Full time

Job summary

United States Digital Space LLC is seeking engineers to own critical APIs end-to-end and shape the boundary between infrastructure and external world for agents and developers.

You’ll design, implement, and deploy high-load services in Go, Rust, and Python, while contributing to developer-facing tooling and platform surfaces. Expect collaboration with product, research, and GTM teams.

Qualifications

• Experience designing and operating distributed, high-load systems.
• Experience building with frontier models and tools, open or closed source.
• Strong product sense: design for developers and customers, anticipating next needs.

Responsibilities

• Own critical APIs end-to-end: RFCs, implement, deploy, monitor and iterate.
• Contribute to product codebases in Go, Rust, Python.
• Build surfaces consumed by agents: hosted MCP, tool calling, connectors, auth flows.

Skills

Distributed systems design

API design

Developer-focused thinking

Tools

Go

Rust

Python

Kubernetes

CI/CD

Security best practices

Job description

the company is looking for engineers who want to put planet-scale search in the hands of every developer and every agent. The API Platform is one of the fastest-growing surfaces of the company, and the team behind it owns all of it. The Search API, the Agent API, agent first SDKs, docs - from the request path to the developer experience. You'll work at the boundary where the company's infrastructure meets the outside world, and you'll shape what that boundary looks like as agents become the dominant consumers of APIs.

We build with AI, for people who build with AI. If you spend your days working alongside frontier models and tooling, you already know where today's developer platforms fall short and that instinct is exactly what we're hiring for.

There are two ways into this team, and we're hiring for both: the product-minded API engineer who cares about schema design, SDK ergonomics, and a developer's first five minutes with the platform, and the infra-leaning platform engineer who cares about progressive delivery, observability, and keeping a high-traffic API stack fast and boringly reliable. The daily work mixes both - come in from whichever side is yours.

What you\'ll do

• Own critical APIs end to end: write the RFC, ship the implementation, roll it out from staging through canary to full fleet, and keep iterating after launch.

• Contribute directly to product codebases across Go, Rust, Python.

• Build the surfaces agents consume: hosted MCP, tool calling, connectors, and auth flows that let agents onboard and operate on their own.

• Harden the platform for enterprise use: authentication patterns, data-handling guarantees, guardrails, and the security posture of a public API under real load.

• Own what you run in production: monitors and dashboards as code, alerts that page you, postmortems you write and act on.

• Partner with Research to evaluate frontier capabilities and turn the promising ones into production API features; work with Product, GTM, and customers directly to find the gaps between what builders need and what the platform offers today.

What we look for

• Experience with designing and operating distributed, high-load systems.

• Build with frontier models and tools - open source and closed source - every day, and you can walk us through your agentic workflow in detail.

• High autonomy and agency, paired with real product sense: you think about developers and customers, what an API user wants next, and where the frontier is heading..

• Working fluency with the core cloud infrastructure stack: a major cloud provider, Kubernetes, CI/CD.

• Depth on at least one side of the role: API product craft or platform operations, and genuine interest in the other.

Nice to have

These are a bonus, not a requirement.

• You've built your own agent loops or harnesses: the fastest way to stand out.

• You've built developer or API tooling in the LLM ecosystem or in adjacent domains where API schemas evolve fast under real customer load, such as fintech or payments.

• You've contributed to open-source SDKs, frameworks, or integrations that developers actually use.