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Senior Product Manager

Harmonic Security IncLondon🇬🇧United KingdomPosted 3 Oct 2026

Quick Overview

Seniority
Mid Senior
Employment type
Full Time
Work mode
Hybrid
Location
London, United Kingdom
Posted
9 hours ago
Business DevelopmentUnity

Job Description

AI is being run everywhere, by humans and agents. Harmonic Security governs all of it. The AI Governance and Control (AIGC) platform understands user / agent intent and data context in real time, giving security teams visibility and control across every tool and workflow so companies can move faster with AI while minimizing risk.

We operate in one of the fastest-moving spaces in tech: the emerging intersection of AI and cybersecurity. It's a market still being defined, and we're among the first to build natively for it - protecting sensitive data in real time, at the endpoint, with minimal friction for the teams using it. Enterprises get full visibility and control. Their people get to innovate without guardrails slowing them down.

Named to the Rising in Cyber 2026 list, Harmonic is gaining serious recognition and serious traction. We're led by deep cybersecurity expertise and backed by investors who know the space: N47, Ten Eleven Ventures, and In-Q-Tel.

As AI adoption inside the enterprise accelerates, the ability to safely observe, control, and enforce policy in real time isn't a nice-to-have. It's mission-critical infrastructure. That's what we build.

How We Work: AI-First by Design

Harmonic exists to help enterprises adopt AI safely and at scale. We hold ourselves to that same standard. Everyone here actively leverages AI tools to perform their best work, from deep research and writing to building robust processes and automating complex workflows. We expect every new hire to bring a genuine curiosity for AI and a commitment to using it to work smarter, faster, and with greater creativity.

For some, this involves tinkering and remaining open to emerging tools; for others, it means architecting entirely new systems with AI at the core. We will be transparent about expectations for every role and provide the tools and support needed for you to thrive.

The role

We're looking for a Senior Product Manager who will start by owning our APIs, webhooks and integrations, and the value they deliver for customers. That means bringing Harmonic's AI Risk and Usage Intelligence into the tools our customers already use, and letting them set controls and policies without leaving their existing workflows. Over time it will also mean making it easier for partners to build with us, and shaping how AI agents connect to tools and data. You'll treat integrations as a product with real users, not just plumbing, and you'll decide which connections matter most and build them well. As Harmonic grows, we expect the scope of the role to grow with it.

The market we work in changes quickly enough that we need everyone in product to have a view on where it's heading. In this role, that view is about the ecosystem around us: which platforms our customers are standardising on and where Harmonic needs to connect to them in a year's time. We'll expect you to form that view and hold it with conviction, even when challenged by others.

What You'll Do

  • Owning our APIs, webhooks, MCP servers and integrations end to end, deciding what gets built, for whom and in what order, and being able to defend that order clearly.

  • Collaborating with our commercial and partnerships teams to understand where integrations and partner opportunities create real value for customers, and translating that into products people use.

  • Deciding which integrations are worth building and which aren't, using your judgement and understanding of our other product areas to determine where the benefits can be felt the most.

  • Holding technical conversations with engineers, both ours and those at partners and customers, covering API design, authentication, and common integration patterns to understand how systems fit together and how they might break.

  • Spending real time with existing customers and prospects, including sales calls and proof-of-value engagements where an integration can make or break a deal, and holding your own in conversations with CISOs, CIOs and their technical teams.

  • Getting hands-on yourself, whether that means calling an API to see how it really behaves, testing a webhook flow end to end, reading a partner's documentation to assess how hard an integration will be, or prototyping to test an idea before more time is committed.

  • Producing work, whether that's discovery, specifications or written thinking, that is clear and technically sound enough to stand up to scrutiny from engineers without needing to be fully rebuilt.

What You'll Bring

You've owned meaningful product work end to end and seen it through to customers, and you can talk not only about what you shipped but about whether it worked and how you knew. You have strong fundamentals to go with that: your writing is clear, your discovery is sound, your prioritisation holds up when someone pushes on it, and you take pride in your quality of work.

You're comfortable being technical. You don't need to write production code, but you're comfortable designing and critiquing APIs, you understand how webhooks, authentication and data flows work in practice, and you can work through detail confidently with engineers. You understand that the people using your products are often developers whose expectations may be very different from those of an end user. You also follow how emerging protocols such as MCP and A2A are changing the way products and AI agents connect, and use this to inform your view of how Harmonic should integrate.

You're also energised by the reality of a startup, where priorities shift, information is incomplete and you'll often need to work out the right approach as you go rather than follow one that already exists.

Nice to have

  • Experience working alongside business development or partnerships teams, and an understanding of what makes a technology partnership succeed or quietly stall.

  • Experience in B2B, particularly selling to and working with large enterprises.

  • A background in security, data protection or a related field, or familiarity with the tools enterprise security teams already run. This genuinely isn't a requirement, because we care far more about how quickly you can get to grips with a domain than whether you already know this one.

  • You live and breathe AI trends and latest developments to apply it directly in your role

Why Join Us

This isn't just a job - it's a chance to help define a category. Harmonic Security was named to the Rising in Cyber 2026 list, and we're just getting started. We're building at the intersection of AI and security, carving out an emerging market where the rules haven't been written yet, and the people who join now will write them.

We believe today's talent is tomorrow's success, and we're committed to creating an environment where you can do the best work of your life.

  • Recognized momentum - We made the Rising in Cyber 2026 list, a signal that the market is taking notice

  • Rare market opportunity - Join early in a category-defining company at the convergence of AI and security, where your work directly shapes how enterprises tackle one of the biggest unsolved problems in tech

  • Competitive pay and meaningful equity - A real stake in Harmonic's success, not a token gesture

  • Comprehensive benefits - pension plan and flexible hybrid work

  • A small, high-trust team that values transparency, creativity, and continuous learning - no politics, no bureaucracy

  • Thoughtful leadership - that cares deeply about your growth, not just your output

  • Annual global off-sites - past trips include Lisbon, Portugal and Nashville, TN

  • Real ownership - you'll shape the product, the culture, and the direction of the company from day one

Harmonic's Core Values

🌱 Flourish in the Unknown

We embrace new, unfamiliar situations that require initiative and rapid decision-making. We orient ourselves quickly and deliver results with minimal guidance.

🔥 Never Full

We raise our hands, take on challenges, and assist others whenever possible. We hunger for opportunities to learn and do more.

🤝 Perfect Harmony

We support one another to create cohesion and unity. We collaborate openly, share feedback honestly, and help everyone produce their best work