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 Equal Opportunity Statement We are an equal opportunity employer and value a diverse, inclusive workplace. We do not discriminate on the basis of race, religion, color, national origin, gender, sexual orientation, gender identity or expression, age, marital or veteran status, pregnancy, disability, or any other protected characteristic. We are committed to providing reasonable accommodations throughout the application and employment process. Notice to Recruiters and Agencies Under no circumstances will Antithesis pay a fee for candidates submitted or presented without a signed recruiting agreement in place between Antithesis and the recruiter or agency prior to submission. Any submission must be for a requisition specifically and individually assigned in writing by Antithesis' People Department. In the event that candidate(s) are submitted or presented to Antithesis by a recruiter or agency without both a signed agreement and written assignment from Antithesis, Antithesis expresses the right to pursue and hire such candidate(s) without any financial obligation to the recruiter or agency.
May 30, 2026
Full time
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 Equal Opportunity Statement We are an equal opportunity employer and value a diverse, inclusive workplace. We do not discriminate on the basis of race, religion, color, national origin, gender, sexual orientation, gender identity or expression, age, marital or veteran status, pregnancy, disability, or any other protected characteristic. We are committed to providing reasonable accommodations throughout the application and employment process. Notice to Recruiters and Agencies Under no circumstances will Antithesis pay a fee for candidates submitted or presented without a signed recruiting agreement in place between Antithesis and the recruiter or agency prior to submission. Any submission must be for a requisition specifically and individually assigned in writing by Antithesis' People Department. In the event that candidate(s) are submitted or presented to Antithesis by a recruiter or agency without both a signed agreement and written assignment from Antithesis, Antithesis expresses the right to pursue and hire such candidate(s) without any financial obligation to the recruiter or agency.
A technology firm is seeking Senior to Staff engineers to join their team and help build the future of autonomous testing. The role requires proficiency in Rust and experience with property-based testing. You'll maintain the open-source project Bombadil and work with various technologies like Chromium automation. This is a hybrid position based in London, emphasizing in-person interactions to build trust and knowledge sharing among team members.
May 30, 2026
Full time
A technology firm is seeking Senior to Staff engineers to join their team and help build the future of autonomous testing. The role requires proficiency in Rust and experience with property-based testing. You'll maintain the open-source project Bombadil and work with various technologies like Chromium automation. This is a hybrid position based in London, emphasizing in-person interactions to build trust and knowledge sharing among team members.
About Antithesis Engineers at Antithesis work across a wide range of domains, often developing their own tools along the way. They dig deep to understand how something really works but stay broad to ship features across the whole stack. The ideal Antithesis engineer is a generalist who loves to learn new things and will fearlessly hack on whatever is needed. The core requirements: you're smart, get things done, and a joy to work with. About the Role We're looking for engineers in the Senior to Staff levels to build the future of autonomous testing. No matter your particular field of experience, if you've been ambitiously building complex software and think you could be a fit; drop us a note. In this role you will be part of the team that maintains our open-source project Bombadil (). This includes working with the specification language and verifier, Chromium automation, advanced property-based testing, frontend development, and much more. Must have for this role: Proficient in Rust development Experience with property-based testing or fuzzing Comfortable with web technology (browsers, HTTP, HTML, Javascript, CSS) Experience that would be a plus: Chrome Devtools Protocol, Playwright, Cypress, or Selenium Formal specification languages (e.g. TLA+ or some LTL) Implementing parsers, type systems, and interpreters The Culture Our team is composed of people with a variety of backgrounds: standard engineering degrees to philosophy degrees; big-tech backgrounds to scrappy startups. But we have at least one common skill: everyone on the team, including managers, is held to the same high standard of engineering competency. In addition, we value in-person work for its value in building trust and sharing knowledge and mentoring each other. Note: This is an 5 days a week in-office job in London, UK
May 30, 2026
Full time
About Antithesis Engineers at Antithesis work across a wide range of domains, often developing their own tools along the way. They dig deep to understand how something really works but stay broad to ship features across the whole stack. The ideal Antithesis engineer is a generalist who loves to learn new things and will fearlessly hack on whatever is needed. The core requirements: you're smart, get things done, and a joy to work with. About the Role We're looking for engineers in the Senior to Staff levels to build the future of autonomous testing. No matter your particular field of experience, if you've been ambitiously building complex software and think you could be a fit; drop us a note. In this role you will be part of the team that maintains our open-source project Bombadil (). This includes working with the specification language and verifier, Chromium automation, advanced property-based testing, frontend development, and much more. Must have for this role: Proficient in Rust development Experience with property-based testing or fuzzing Comfortable with web technology (browsers, HTTP, HTML, Javascript, CSS) Experience that would be a plus: Chrome Devtools Protocol, Playwright, Cypress, or Selenium Formal specification languages (e.g. TLA+ or some LTL) Implementing parsers, type systems, and interpreters The Culture Our team is composed of people with a variety of backgrounds: standard engineering degrees to philosophy degrees; big-tech backgrounds to scrappy startups. But we have at least one common skill: everyone on the team, including managers, is held to the same high standard of engineering competency. In addition, we value in-person work for its value in building trust and sharing knowledge and mentoring each other. Note: This is an 5 days a week in-office job in London, UK
A technology company in London is seeking an experienced Product Manager to lead the Property-Based Testing product area. This role requires defining product initiatives, conducting customer discovery sessions, and collaborating with engineering teams. Ideal candidates should have a startup background, experience defining developer-facing APIs, and strong communication skills. The position offers significant influence in a technical environment focused on innovative software testing solutions.
May 30, 2026
Full time
A technology company in London is seeking an experienced Product Manager to lead the Property-Based Testing product area. This role requires defining product initiatives, conducting customer discovery sessions, and collaborating with engineering teams. Ideal candidates should have a startup background, experience defining developer-facing APIs, and strong communication skills. The position offers significant influence in a technical environment focused on innovative software testing solutions.
Antithesis Operations LLC is seeking a developer based in London to help build 'Hegel', an innovative set of property-based testing libraries. The role requires experience with property-based testing and familiarity with Python and Rust. This in-office position values collaboration and high engineering standards across a diverse team. Candidates should be comfortable working with AI assistance and maintaining quality in software development. This job is a fantastic opportunity to contribute to open source and work on cutting-edge technology.
May 29, 2026
Full time
Antithesis Operations LLC is seeking a developer based in London to help build 'Hegel', an innovative set of property-based testing libraries. The role requires experience with property-based testing and familiarity with Python and Rust. This in-office position values collaboration and high engineering standards across a diverse team. Candidates should be comfortable working with AI assistance and maintaining quality in software development. This job is a fantastic opportunity to contribute to open source and work on cutting-edge technology.
About Antithesis We've been quietly reinventing how the world thinks about software reliability, and we're just getting started! At Antithesis, we start at the foundations - we run entire software systems inside a deterministic simulation and break them in every way imaginable. Every issue then comes with a perfect reproduction, so you can identify root causes fast instead of spending days trying to recreate what went wrong. The rise of AI-generated code has made this work more urgent than ever. Agents can write code faster than any human, but speed doesn't matter much when the output is buggy, stuck in review, or slipping through undetected. The verification bottleneck is real, it's growing, and solving it is one of the most consequential problems in software right now. That's what you'd be working on. We're well-funded and deeply technical, the kind of place where the hardest problems get the most attention and the best ideas win regardless of who has them. If you want to do work that actually moves the needle on how reliable software can be, keep reading. About the Role: This role, on a team based in London, is responsible for building out Hegel, our new family of property-based testing libraries. We are building open source libraries to provide top quality property-based testing in every language, both for the benefit of the community at large, and because it provides a natural on-ramp for potential customers to test their software in Antithesis. Must have for this role: Experience using property-based testing (PBT). Experience with Hypothesis would be slightly preferred but experience with any other PBT library is fine too. We lean heavily on AI assistance in developing Hegel, with a lot of human review and care to maintain quality. You don't need to have any experience with such workflows, but you should be comfortable with the idea of using them. Nice to haves: Familiarity with at least one, ideally both, of Python and Rust. Willingness to work in a variety of languages. Expert-level in at least one language that you would be keen to be "tastemaker" for a Hegel implementation. Having maintained an active open source library is a strong plus. The Tech: You can see most of the tech in question on hegel-core is Python, and hegel-rust is our most mature client library. We also have go, typescript, C++, and OCaml (some not yet public). We're not immediately planning to support more, but if there's some language you'd be keen to add support for feel free to let us know. We are heavy Claude Code users. Antithesis more broadly are heavy Nix users, and it would be a plus to be familiar with that, but because Hegel integrates with existing language package managers we are not actually heavy users of it on this team in particular. The Culture Our team is composed of people with a variety of backgrounds: standard engineering degrees to philosophy degrees; big-tech backgrounds to scrappy startups. But we have at least one common skill: everyone on the team, including managers, is held to the same high standard of engineering competency. In addition, we value in-person work for its value in building trust and sharing knowledge and mentoring each other. Note: This is an 5 days a week in-office job in London, UK
May 29, 2026
Full time
About Antithesis We've been quietly reinventing how the world thinks about software reliability, and we're just getting started! At Antithesis, we start at the foundations - we run entire software systems inside a deterministic simulation and break them in every way imaginable. Every issue then comes with a perfect reproduction, so you can identify root causes fast instead of spending days trying to recreate what went wrong. The rise of AI-generated code has made this work more urgent than ever. Agents can write code faster than any human, but speed doesn't matter much when the output is buggy, stuck in review, or slipping through undetected. The verification bottleneck is real, it's growing, and solving it is one of the most consequential problems in software right now. That's what you'd be working on. We're well-funded and deeply technical, the kind of place where the hardest problems get the most attention and the best ideas win regardless of who has them. If you want to do work that actually moves the needle on how reliable software can be, keep reading. About the Role: This role, on a team based in London, is responsible for building out Hegel, our new family of property-based testing libraries. We are building open source libraries to provide top quality property-based testing in every language, both for the benefit of the community at large, and because it provides a natural on-ramp for potential customers to test their software in Antithesis. Must have for this role: Experience using property-based testing (PBT). Experience with Hypothesis would be slightly preferred but experience with any other PBT library is fine too. We lean heavily on AI assistance in developing Hegel, with a lot of human review and care to maintain quality. You don't need to have any experience with such workflows, but you should be comfortable with the idea of using them. Nice to haves: Familiarity with at least one, ideally both, of Python and Rust. Willingness to work in a variety of languages. Expert-level in at least one language that you would be keen to be "tastemaker" for a Hegel implementation. Having maintained an active open source library is a strong plus. The Tech: You can see most of the tech in question on hegel-core is Python, and hegel-rust is our most mature client library. We also have go, typescript, C++, and OCaml (some not yet public). We're not immediately planning to support more, but if there's some language you'd be keen to add support for feel free to let us know. We are heavy Claude Code users. Antithesis more broadly are heavy Nix users, and it would be a plus to be familiar with that, but because Hegel integrates with existing language package managers we are not actually heavy users of it on this team in particular. The Culture Our team is composed of people with a variety of backgrounds: standard engineering degrees to philosophy degrees; big-tech backgrounds to scrappy startups. But we have at least one common skill: everyone on the team, including managers, is held to the same high standard of engineering competency. In addition, we value in-person work for its value in building trust and sharing knowledge and mentoring each other. Note: This is an 5 days a week in-office job in London, UK