Staff Backend Engineer

Staff Backend Engineer

We're looking for a top-tier Staff Backend Engineer to join our tech team.

You'll wear many hats. Your core responsibilities will be to:

• Design internet-scale, high-performance infrastructure
• Build robust products- develop, deploy, and maintain new features end-to-end
• Master the technical scope of your domain and raise the bar for engineering quality
• Collaborate on road-mapping and drive key technical decisions
• Own large cross-functional initiatives from conception to delivery
• Work autonomously alongside the CTO and the rest of the Software & ML teams
• Conduct code reviews and foster knowledge-sharing across the team

Requirements

You're a great match if you:

• Are excited to help build Google for AI agents- and believe in Linkup's mission
• Have extensive backend experience building and operating large-scale distributed systems (6y minimum)
• Enjoy optimizing systems—shaving off milliseconds and making GPUs "go brrr"
• Bring experience with, or strong curiosity about, AI technologies and a commitment to continuous learning
• Possess a solid grasp of infrastructure and CI/CD best practices
• Thrive in a fast-paced environment and aren't afraid to work hard to achieve ambitious goals

Example Projects

• Index hundred of millions of web pages every day, with <5 min freshness
• Add multimodal search (text + images + audio) under 150 ms
• Stream 1 B embeddings / day for while minimizing compute costs
• Auto-retrain ranking on agent clicks every 24 h

Our Stack

• Node.js / NestJS
• React
• Python
• Java
• PostgreSQL
• OpenSearch
• Vespa
• Apache Storm
• vLLM
• Kubernetes
• GitHub Actions
• Terraform

Details

The ideal candidate will play a central role in our engineering team, partnering closely with the founders to spearhead groundbreaking products. Your backend expertise will shape the future of AI-powered applications and bring our vision to life.

We offer a flexible remote-work policy- see the details here.

Join us and leverage your expertise to push the boundaries of AI!

Our Vision

We believe in a future of AI agents and the agentic web. These digital entities can create more value for humanity than we ever could alone, but they depend on the internet to operate, collaborate, take action, and gather information.

AI agents need web search. To perform well, they require information that is current, reliable, and context-specific—not the diffuse, steadily aging knowledge frozen at their last training cut-off.

Modern web search is built for humans, not AIs. Instead of trusted facts, it serves links, ads, and click-bait. People want visually engaging pages; AI systems need structured truth. An AI can absorb oceans of data, while human attention barely skims the surface. Humans think visually and intuitively; AI reasons in latent space.

Web 2.0 is sunsetting. The deck is being reshuffled, and the Bing-Google search oligopoly is crumbling. Indexing ever more pages is no longer the goal; semantically organizing facts for AI systems is. In the coming agentic web, Google's ad-driven model has no natural home.

Search for AI must be rebuilt from the ground up. We are reconstructing the web as a rigorously structured knowledge layer, mapping every concept, entity, and claim into a coherent semantic graph. This foundation delivers verified facts and rich context to AI instantly, unlocking faster reasoning, higher accuracy, and radically more useful answers for everyone.

Humans search Google; AI searches Linkup.

Our Mission

Reality never stands still, and neither should intelligence. Linkup reconnects language models to a living stream of verified facts, ensuring AIs remain as current and insightful as the world they serve.

Our mission is to deliver the world's freshest, most trusted knowledge to AIs.

Our Culture

Our culture is built on the following values:

• Mission. We believe we play a critical role in building the agentic web. We are 100% committed to our mission of bringing the reality of the world to AI agents.
• Speed. We build fast, we build to last. We get things done, well.
• Ownership. We empower every team member to take ownership of their projects, ensuring they see them through to successful completion.
• Teamwork. Our strength lies in our unity. We rely on one another and embrace our diversity as a core asset.
• Humility. We maintain low egos, showing respect for others and continuously learning from their insights and experiences.

We expect all team members to take an active role in shaping our company culture.

Our Team

We are a small technical team, working shoulder to shoulder to build the web of agents.

A bit more about our 3 co-founders:

• Philippe Mizrahi- Led the development of Lyft's Autonomous Vehicles marketplace. Previously launched Amundsen, an open source search engine.
• Denis Charrier - Founding Engineer at Niland, an audio search company (acquired by Spotify), then Staff Engineer at Spotify. 15y of software development experience.
• Boris Toledano - Led robotics at Carrefour, after 3y at McKinsey & Co working on public affairs and digital transformation.