Senior Software Engineer, Full Stack

Antithesis

Vienna, VA

On-site

Who this role is best for

Candidates with experience in building customer-facing products and strong technical skills in algorithms and data structures will find this full-stack role with a focus on reactive computing platforms and AI verification highly aligned with their background.

Best fit for

Candidates with a history of building static and dynamic websites and a deep understanding of browser mechanics
— “Understanding of how the internet and browsers work”
Individuals comfortable with Typescript and open to learning Rust for system-level tasks
— “Be very comfortable with Typescript, and ready to pick up a bit of Rust work”

Things to consider

The role may require familiarity with Nix for deployment, which is not commonly used in many software environments
— “Develop build and deployment logic in Nix”

How to stand out

Highlight your experience in creating end-to-end features with a focus on customer-facing impact
— “Own a new feature, from the front end to the data layer”
Demonstrate your ability to design and implement property-based tests for robustness
— “Create Property Based Tests and Antithesis workloads to test the things you create”
Showcase your work with AI tools, particularly in code generation or verification contexts
— “have ideas about leveraging AI effectively”

Pace · Fast PacedCollaboration · HighAutonomy · HighDecision Impact · Team

Derived from job-description analysis by Serendipath's career intelligence engine.

What success looks like

Improvements to a reactive engine for executing Javascript
Ownership of a new feature from front end to data layer
Development of build and deployment logic in Nix

Typical background

Experience working with complex customer facing-productsStrong technical skills and solid programming background

Skills & requirements

Required

TypeScriptJavaScriptAlgorithmsData StructuresStatic And Dynamic WebsitesInternet And Browsers

Preferred

RustNixProperty Based TestingAI

Stack & domain

TypeScriptRustAlgorithmsData StructuresStatic And Dynamic WebsitesInternet And BrowsersNix

About the role

Original posting from Antithesis via Ashby

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:
Antithesis is looking for a Full Stack Engineer to join our engineering team. This role primarily focuses on the Notebook - the reactive computing platform that all Antithesis UX is built on top of. As a Notebook Engineer, you will do a mix of deeply technical and heavily product-focused work.
WHAT YOU’LL DO:
Make improvements to a reactive engine for executing Javascript (imagine Jupyter where everything auto recalcs).
Own a new feature, from the front end to the data layer. This includes adding features as needed to our custom database (or proxy, or API server) to get the feature done.
Create Property Based Tests and Antithesis workloads to test the things you create.
Work with our product managers to design and scope features.
Develop build and deployment logic in Nix.
WHAT WE’RE LOOKING FOR:
Experience working with complex customer facing-products.
Be very comfortable with Typescript, and ready to pick up a bit of Rust work.
Have strong technical skills and a solid programming background in algorithms and data structures.
Experience building static and dynamic websites
Understanding of how the internet and browsers work
(bonus) experience with Nix
(bonus) have ideas about leveraging AI effectively
(bonus) a prior history with PBT

Source: Antithesis careers (Ashby)