Senior Product Manager
About Antithesis
Antithesis is building a fundamentally new approach to software testing. Our platform uses advanced fuzzing and property-based testing techniques to find deep bugs in customer software and exercise systems in ways that traditional testing cannot.
We are in the early stages of productizing a powerful underlying technology. That means much of our product surface, operating model, and customer workflows are still being defined. This is a high-ambiguity, 0→1 environment where product judgment matters.
About the Role
We are hiring Product Managers to own critical parts of the Antithesis product.
This is not a purely executional role inside an established system. You will operate in a fast-moving, technical environment where many decisions are first-of-their-kind. You will help define product areas, shape workflows, influence prioritization, determine how we measure success, and partner closely with engineering and design to build durable foundations.
You will operate in a technical, engineering-heavy environment where problems are complex and tradeoffs are real. You’ll work closely with engineers to define what we build, why we build it, and how we measure success.
This is not a role for someone who wants to run process or optimize a mature product. It’s a role for someone who wants to build.
Areas of Focus
We are looking for a London-based product manager to own the Property-Based Testing (PBT) and Specification product area. This area includes, but is not limited to:
How customers expose their software for Antithesis to exercise during a test.
How customers tell us what behavior is expected or not expected of their software.
How customers tell us which kinds of issues they do or do not care about.
How customers provide us with guidance on what areas of their code are most interesting to explore.
The Antithesis SDK.
You will work closely with the Antithesis PBT technical team, based out of the London office, which includes world experts on property-based testing.
What You’ll Do
Conduct discovery sessions with customers and understand their needs
Define and prioritize product initiatives within your area
Work with engineering to scope and ship high-impact features
Make tradeoffs in ambiguous and technically complex situations
Define metrics and evaluate outcomes
Collaborate with GTM and customers to refine requirements
Write clear product briefs and problem statements
What We’re Looking For
Strong Signals:
Startup experience
Experience defining developer-facing APIs or abstractions
Comfort operating under ambiguity
Evidence of thoughtful prioritization and decision-making
Strong written communication
Nice to Have:
Experience with property-based testing, fuzzing, and/or formal verification
Experience with distributed systems
Software testing background
Not a Fit If
You focus primarily on implementing PM frameworks or process
Your experience centers on optimizing mature systems without building new ones
You prefer highly structured environments with predefined playbooks
