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About XBuild

XBuild is building the back office that runs itself for contractors. Headquarters connects every system a contractor runs into one record of the business, and Rex, our AI operator, runs the work on top of it: building estimates and supplements from photos and measurements, chasing unpaid invoices, following up on stale leads. More than 1,000 companies doing $25B+ a year in work run on XBuild, and we've raised $25M+ from a16z and N47.

The role

You'll be our first dedicated security and infrastructure hire, and you'll own both. Contractors trust us with their customers' homes, insurance claims, photos and financials, and enterprise customers will check that we deserve it. AI makes attackers faster and gives us new attack surface: an agent that reads untrusted documents and acts on customer data. We want someone who has built a security program from zero, still writes the infrastructure code themselves, and also makes our engineers faster.

What you'll own

Security: threat models, access control and tenant isolation, secrets, vulnerability and dependency management, detection and incident response. You'll write and test the incident plan.
AI security: guardrails for Rex and our other agents, covering prompt injection, tool permissions, data boundaries between companies, and red-teaming.
Compliance: run our assessments and certifications, answer enterprise security questionnaires, and join security reviews on large deals.
Infrastructure: our GCP footprint (Cloud Run, Cloud Deploy, IAM, networking), Firebase and Firestore, infrastructure as code, ","datePosted":"2026-11-05","employmentType":"FULL_TIME","hiringOrganization":{"@type":"Organization","name":"XBuild","sameAs":"https://www.x.build/"},"url":"https://jobs.ashbyhq.com/xbuild/8761ed97-7289-4307-98a4-ca009a19e0ac","jobLocationType":"TELECOMMUTE","jobLocation":{"@type":"Place","address":{"@type":"PostalAddress","addressLocality":"San Francisco"}}},{"@context":"https://schema.org","@type":"JobPosting","title":"Forward Deployed Engineer","description":"
About XBuild
XBuild is building the back office that runs itself for contractors. Headquarters connects every system a contractor runs into one record of the business, and Rex, our AI operator, runs the work on top of it: building estimates and supplements from photos and measurements, chasing unpaid invoices, following up on stale leads. More than 1,000 companies doing $25B+ a year in work run on XBuild, and we've raised $25M+ from a16z and N47.
The role
You'll be the engineer our largest customers rely on. When a multi-location contractor decides to run its business on Headquarters, you make it happen. You map their years of data out of the systems they use today and migrate it. You configure Headquarters for how they work, and you build the features that turn a pilot into a company-wide rollout. You'll be in the room for big deals, and often the reason we win them.
What you'll do
- Run technical discovery with owners, operations leaders and IT at enterprise contractors.
- Plan, build and run data migrations from CRMs, estimating tools and spreadsheets into Headquarters, and make sure the numbers reconcile.
- Configure and customize: price books, packages, templates, workflows, integrations through our API.
- Ship product code for features that unlock deals, working with the product team so each one makes Headquarters better for every customer.
- Answer the technical half of sales: security reviews, integration questions, pilots.
- Bring what you learn back to the team: what customers really need and where the product falls short.
- About XBuild
  XBuild is building the back office that runs itself for contractors. Headquarters connects every system a contractor runs into one record of the business, and Rex, our AI operator, runs the work on top of it: building estimates and supplements from photos and measurements, chasing unpaid invoices, following up on stale leads. More than 1,000 companies doing $25B+ a year in work run on XBuild, and we've raised $25M+ from a16z and N47.
  The role
  You'll ship product, a lot of it, for an industry that has been underserved by software for decades. Some weeks you'll be deep in Rex or Headquarters: agent tools, evals, prompts, and the hard question of whether the estimate is actually right. Other weeks you'll take a feature from a customer call to production in days. You'll often run several of these at once, with AI agents doing much of the typing and you doing the thinking.
  What you'll do
  - Ship features end to end across our Python/FastAPI backend, our Next.js web app and our React Native mobile app.
  - Build and improve Rex and the Headquarters platform: new tools and actions, connectors to contractor systems, evals that prove the model does the right thing.
  - Talk to contractors directly, and decide what to build and what to skip.
  - Own what you ship in production: monitor it, fix it, make it better.
  - Raise the bar for how a small team uses AI to build software.
  You might be a fit if you
  - Have shipped a lot of real products or features, and can show us.

About XBuild

The role

What you'll own

About XBuild

The role

What you'll do

The role

What you'll do

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