As the first technical hire, you will own the architectural evolution of an agentic workflow platform. Transitioning the codebase from the technical co-founder, you'll build robust systems that convert real-world behaviors into reliable AI automations. You will bridge the gap between complex LLM orchestration and seamless user experiences for non-technical teams.
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London, UK£100K + 2% Equity
Featured roleLondon, UK£100K + 2% Equity
Principal Engineer at Rivulo.ai
Rivulo.ai is looking for its first Principal Engineer to lead the technical evolution of our agentic workflow platform. Founded by award-winning serial entrepreneurs, we’ve just closed our funding round and are ready to scale. This is a rare opportunity to own the architectural direction of a high-growth AI startup, moving from v1 to a robust multi-model system. If you want radical transparency, 2% equity, and the autonomy to build without management layers, this is your next move.
Overview
Why this role stands out
Company
Responsibilities
What you will do
- Evolve the platform architecture from v1 MVP to a scalable, production-grade system capable of handling thousands of concurrent AI workflows.
- Design and implement sophisticated LLM integrations, focusing on prompt engineering, token management, and real-time streaming reliability across OpenAI, Anthropic, and Google APIs.
- Collaborate directly with customers to understand friction points, translating messy real-world operational needs into elegant, automated agent-led systems.
Candidate profile
Who this is a fit for
- Expert full-stack engineer with deep TypeScript/JavaScript proficiency and professional experience (or a strong willingness to master) PHP/Laravel 12.
- Proven track record in AI Engineering, including hands-on experience with LLM context window optimization, rate limiting, and building resilient retry logic for real-time interfaces.
- Entrepreneurial builder who thrives in autonomous environments, possesses a "founder mindset," and is comfortable jumping into product or support tasks to drive company growth.
What makes it remarkable
Why this role is remarkable
- Take total technical ownership as the first engineering hire, working directly with experienced founders who have multiple successful exits.
- Build at the cutting edge of AI, moving beyond simple wrappers to create complex, multi-model orchestration and autonomous browser automation systems.
- Experience a high-trust, radical transparency culture with self-management, full financial visibility, and the autonomy to make major architectural decisions without red tape.
Jack & Jill
How Jack & Jill work together
I get to know what you’re great at, then find roles you’d never find yourself.Ok, I'll go first. I'm Jack, an AI that gets to know you on a quick call, learning what you're great at and what you want from your career. Then I help you land your dream job by finding unmissable opportunities as they come up, supporting you with applications, interview prep, and moral support.
I recruit from Jack’s network and make the intro when I spot a great match.And I'm Jill, an AI Recruiter who talks to companies to understand who they're looking to hire. Then I recruit from Jack's network, making an introduction when I spot an excellent candidate.
About Jack & Jill
Meet Jack
Jack gets to know what you are great at, what you want next, and makes sure Jill considers you for the right opportunities.
How does this work?
Jack's an AI agent for job searching and career coaching. He works for you.
Jill is the AI recruiter working for the company. She recruits from Jack's network.
If it's a match and the company wants to meet you, they'll make the intro. In the meantime, if you'd like, Jack will send you excellent alternatives.
Jack