Bug-free systems,
unlimited velocity:
Faster change verification
Severe bugs found that all other testing missed
Faster time-to-release with fewer critical failures
Building concurrent, complex software has always been hard. Networks, disks, clocks, and schedulers misbehave. Unanticipated inputs trigger dormant bugs. Pathologic interactions between components emerge under load. Even the most thorough unit and integration tests miss these unknown unknowns, so seasoned engineers rely on careful code review, long pre-release stress tests, and unrelenting paranoia.
AI raises the stakes. As the cost of producing code plummets, the pressure to ship faster rises — but the time required to review, test, and trust each change hasn’t budged. Verification is the new bottleneck.
Antithesis compresses years of production hardening into a few minutes, fast enough to run in CI, in the local development loop, or as an agent skill. Our deterministic simulation platform runs your complete system, stresses it with faults and toxic inputs, finds the bugs you didn’t anticipate, and enriches every bug report with a root cause analysis and a perfect reproduction — so every engineer can merge fearlessly.
Unleash your team
Antithesis catches unforeseen bugs in minutes, so humans and agents can ship quickly without risking outages.
Prevent outages
By injecting realistic faults and leveraging our simulator’s unique replay capabilities, we explore the execution paths that even years of traditional testing miss.
Skip debugging
Our simulator is 100% deterministic and automatically root causes every bug. Rather than wasting time and tokens chasing flaky heisenbugs, your team can jump straight to a fix.
Ship faster
When every pull request has already survived the Antithesis gauntlet, your team can merge big changes confidently — even when they’re authored by agents.
Autonomous verification,
not just automated review
Perfect determinism
Deterministic simulation testing goes beyond chaos testing, static analysis, and AI code review: from hypervisor to debugger, our whole stack is designed to efficiently verify your running system.
The foundation of our platform is a custom hypervisor that lets us rewind time, try alternate execution paths, and perfectly reproduce every bug.
Aggressive fault injection
We simulate clock, scheduling, network,
and storage faults to
exercise all your
error-handling code.
Intelligent exploration
Antithesis guides exploration to maximize efficiency, running thousands of distinct scenarios in minutes.
Debugging superpowers
Perfect reproductions, automated root cause analysis, and a time-traveling debugger save time and tokens.
Skills, CLIs, and APIs
Our skills help agents onboard your project, build a specification of its behavior, and call Antithesis in the loop.
Accelerating reliability for elite teams
What would otherwise take six months of testing in production, running the software -- we can get that in an hour.
Clément Salaün
Co-Founder & CTO, Formance
Engineering output
The way Antithesis tests whole-system scenarios that we either wouldn’t have thought to test is its own kind of magic… we feel like we can tackle more ambitious projects by relying on Antithesis to fill in any gaps along the way.
Doug Patti
Software Engineer, Jane StreetAntithesis helped us find three key bugs in Tigris…These are the bugs that CI can't cover because no one thinks to write them.
Adil Ansari
Founding Engineer, Tigris Data
Better coverage than 100 engineers in one year
Antithesis’s deterministic simulation and active exploration removes the blindfold, enabling a systematic and reproducible search for bugs.
Marek Siarkowicz
Kubernetes & etcd MaintainerThere’s been a transformation in the engineering group. With basically the same group of people, output is now significantly better. Antithesis has given us more confidence in what we’re delivering, lower stress development, more predictability… I look at Antithesis as a way of enabling us to scale, and that is just an enormous deal.
Sean Murphy
Co-Founder & CEO, PingThings
Compressed 3 weeks of debugging into one day
With Antithesis, you can make these pretty bold changes that ordinarily you would have to approach so carefully in order to do safely, and you can just kind of write the thing.
Mark Logan
Tech Lead for Sui Core at MystenBuilt for software that can't fail
The latest from the blog
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Causality analysis for Antithesis.
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An exotic data structure and a whole lot of JOINs.
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Love Antithesis, hate the setup process? What if your good friend Claude could do it for you?
Hypothesis, Antithesis, synthesis
Introducing Hegel, our new family of property-based testing libraries.