Founding Developer Evangelist (Enterprise)

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Job title: Founding Developer Evangelist

Location: London; full in-office working as default

Start date: ASAP

Reports to: CRO, with dotted line to CTO and CEO

Compensation: £60k–£90k base (potential to go higher depending on experience) plus equity

Cosine at a glance

• Cosine is an autonomous, on-premise coding agent post-trained on human reasoning data to deliver unmatched software-engineering accuracy, security, and speed for regulated enterprises
• What makes us unique is our in-house ML research lab that post-trains LLMs (e.g. Nova, gpt-oss, Mistral) on proprietary software-engineering reasoning data to dramatically increase their coding accuracy. In 2024 this gave us a world-leading score of 72% on OpenAI’s SWE-Lancer benchmark
• Cosine is now the only available managed product that can be fully air-gapped and deployed on premises, exciting many bulge bracket but extremely risk sensitive and strict enterprises that have rejected all other solutions on the market. We've got our first pilots up and running with global investment banks and defence primes

The role

At Cosine, enterprise adoption depends on technical trust. Autonomous agents are still poorly understood, often oversold, and rarely inspected with the rigour serious engineering teams require.

We are hiring a Founding Developer Evangelist to make Cosine’s technology legible, credible, and evaluable to the world’s most sophisticated engineering teams.

This role sits at the intersection of:

• Deep technical understanding (agents, ML systems, evals, infrastructure)
• Enterprise-facing technical communication
• Hands-on support for real-world evaluations and pilots

Content creation is a core tool, but not the end goal.

The goal is to help enterprises understand, trust, and safely evaluate Cosine.

What You’ll Do

1. Support enterprise evaluations and pilots (core responsibility)

• Act as a technical counterpart to enterprise engineering teams during evaluations, pilots, and early deployments
• Join architecture reviews, technical deep dives, and security-focused conversations
• Explain how Cosine works in practice: its agent architecture, training approach, evaluation methods, and operational constraints
• Help teams understand where Cosine excels, where it currently has limits, and how to evaluate it responsibly
• Identify repeated technical objections, points of confusion, and failure modes encountered during real-world evaluations

2. Create best-in-class technical content (informed by reality)

• Produce long-form technical explainers grounded in real evaluation learnings:
  • Agent architecture and control
  • Evaluation methods (correctness, reliability, long-horizon behaviour)
  • Training approaches and research insights
  • Security, auditability, and on-prem deployment
• Translate research-level concepts into content that CTOs, Staff+ engineers, and technical evaluators can reason about
• Create clear diagrams, walkthroughs, and examples that help engineers form accurate mental models
• Produce high-quality video content where it meaningfully increases clarity or trust

3. Own Cosine’s technical narrative (enterprise-first)

• Develop a coherent, technically rigorous narrative for how Cosine differs from:
  • “AI wrappers”
  • Code assistants
  • Narrow benchmark-driven tools
• Ensure Cosine is understood as:
  • A research-driven ML lab
  • A production-grade autonomous agent platform
• Maintain a consistent voice that emphasises credibility, honesty, and depth, especially for regulated enterprises

4. Capture and feed back real-world technical insights

• Systematically capture insights from enterprise evaluations, including:
  • Where teams get stuck
  • What they distrust
  • Which evals matter most to them
  • What blocks internal approval
• Share structured feedback with product, research, and engineering teams.
• Help shape documentation, evals, and product priorities based on repeated patterns observed in the field.

5. Produce early technical case studies and evaluation write-ups

• Create technically rigorous case studies based on pilots and early deployments
• Focus on what was tested, how it was evaluated, what worked, and what didn’t

How Success Will Be Measured (first 6–12 months)

• Enterprise engineers can accurately explain Cosine’s architecture, evaluation approach, and differentiation after engaging with Cosine.
• Technical objections during evaluations become clearer, fewer, and more repeatable over time.
• Prospective customers report increased confidence in evaluating Cosine safely.
• Insights from enterprise evaluations directly inform product decisions, documentation, and evaluation strategy.
• Sales and leadership rely on this role as a trusted technical voice in high-stakes conversations.

You’ll thrive here if you:

• Have deep technical credibility: you’ve worked as a software engineer, ML engineer, or in a highly technical role and are comfortable reasoning about real systems, trade-offs, and failure modes
• Are fluent in modern ML and agentic systems, including model training and post-training, evaluation methods, long-horizon agent behaviour, and the operational constraints of deploying AI in production environments
• Can engage directly with senior engineers and architects at large enterprises, explain complex systems clearly, and earn trust in high-stakes technical conversations
• Enjoy being close to the action: joining pilots, and technical deep dives to understand where real teams struggle, what they distrust, and what actually blocks adoption
• Can independently investigate a technical topic (including reading research papers or inspecting code) and turn that understanding into clear explanations, diagrams, and written or video content
• Are obsessed with clarity and accurate mental models, and care deeply about helping others understand not just what Cosine does, but how and why it works, including its current limits
• Are energised by working closely with a research-driven engineering team, and enjoy acting as a bridge between cutting-edge ML work and real-world enterprise use cases
• Want autonomy and ownership, and are excited by shaping a function from first principles in a fast-growing company where your judgment and technical taste will matter
• Experience producing polished technical demos, walkthroughs, or explanatory videos is a plus

Equal Opportunity

We’re an equal opportunity employer. We value diverse backgrounds and encourage applications from everyone who meets the role requirements, even if you don’t tick every box.