Wanted: Claude Code operator a Frontend Engineer to help us keep LLMs under control.

About us

White Circle is building the safety, reliability, and optimization layer for AI systems.

At our core are policies — simple natural-language rules that describe what an AI should and should not do, and what users can and cannot do. We test, enforce, and continuously improve these policies automatically.

Core products:

• 🧨 Test — automated red teaming that finds jailbreaks, unsafe tool calls, and other issues.
• 🛡️ Protect — real-time guardrails enforcing policies and blocking bad stuff.
• 🔍 Observe — advanced observability with topic clustering, failure tracing, and risk scoring.
• ⚙️ Improve — continuous prompt and policy optimization for better accuracy, consistency, and latency.

More info:

• 💰 Raised $11M from Hummingbird, Abstract, BoxGroup, SV Angel, Saga VC, Durk Kingma (co-founder of OpenAI), Thomas Wolf (co-founder of HuggingFace), Guillaume Lample (co-founder of Mistral), Romain Huet (head of DevEx at OpenAI), David Cramer (founder of Sentry), Olivier Pomel (founder of Datadog), Francois Chollet (creator of Keras), etc
• 📈 Processing tens of millions of API requests every month

The Role

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Salary: $80–150k + equity

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Location: Paris, France (Hybrid)

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We’re looking for a frontend engineer — someone who loves crafting clean interfaces and isn’t afraid of a complex SQL query.

You will:

• Build fast, reliable UIs for safety dashboards and developer tools.
• Design and implement APIs and data pipelines for analytics and monitoring.
• Work with large datasets in ClickHouse.
• Debug weird browser quirks (yes, Safari, we’re looking at you).

You’ll fit right in if you:

• Know your way around TypeScript, React, Next.js, Tailwind, and GraphQL.
• Have worked with LLMs (OpenAI API, function calling, context management — you get it).
• Can write non-trivial SQL without Googling “group by in window function explained.”
• Care about design, usability, and performance, not just “making it work.”

Why join us?

• No corporate bullshit.
• Tight crew. Small team, zero politics, shared ambition.
• Ownership. We’re a small team, so your decisions will matter from day one.
• High velocity. We iterate fast and don’t wait for permission.
• High standards. We care about craft — code, design, and clarity.
• Direct feedback. No layers, no filters, just honest collaboration.
• It actually matters. We design the systems that keep AI aligned with human values.