Tsenta is building the AI agent that finds and applies to jobs for you. We watch 50,000+ company career pages across 19 ATSes (Workday, Greenhouse, Lever, Ashby, and more), tailor each candidate's resume to the role, and submit real applications on their behalf — over the web, iMessage, a Chrome extension, and an MCP server for coding agents. We're backed by Y Combinator and growing fast. We're hiring our founding engineer — one of the very first people on the team. You'll work shoulder to shoulder with the founders, own large surfaces of the product end to end, and set the technical bar for everyone who comes after you. WHAT YOU'LL DO - Build core product across the full stack — the job-matching engine, resume tailoring, the ATS auto-fill system, and the agent surfaces (web app, Chrome extension, iMessage/WhatsApp, and MCP server). - Reverse-engineer and reliably automate 19+ applicant tracking systems at scale, handling logins, every field type, and open-ended questions. - Ship LLM-powered features that read job descriptions, tailor application materials, and answer open-ended questions in each candidate's voice — accurately and within ATS constraints. - Own features end to end — from design and architecture through deploy, monitoring, and iteration. - Set the engineering culture and standards as one of the first hires, and help us recruit the rest of the team. WHAT WE'RE LOOKING FOR - 3+ years building and shipping production software, ideally at an early-stage startup or in a role with broad ownership. - Strong full-stack ability — comfortable owning everything from the database to the UI, and biased toward shipping. - Experience with web automation, scraping, or browser tooling — or the appetite to go deep on it fast. - Hands-on experience building with LLMs and turning them into reliable, production-grade features. - High autonomy and ownership — you scope ambiguous problems, make calls, and drive them to done. - Excited to work in person, move fast, and help shape an early-stage company. NICE TO HAVE - Experience with one or more ATSes (Workday, Greenhouse, Lever, Ashby, etc.). - Built browser extensions, MCP servers, or agent/tool-use integrations. - Prior founding-engineer or 0-to-1 experience. TECH STACK TypeScript across the stack, with modern web frameworks on the frontend, Node services on the backend, browser automation for the ATS integrations, and LLMs powering matching and tailoring. We care more about how you think and ship than the exact tools on your resume. WHAT YOU'LL GET - Meaningful founding-level equity and competitive salary. - Direct, daily collaboration with the founders and real influence over product and direction. - The chance to build a product people genuinely need, with the support of Y Combinator behind you. HOW TO APPLY Apply through this posting, or email us at founders@tsenta.com. Share anything you've shipped that you're proud of — side projects, repos, or products. We read every application.