About UsZero Hiring is building the AI hiring stack for modern recruiting teams. Our product helps employers run faster, more consistent hiring workflows using AI-led interviews, structured candidate evaluation, and automation across the recruiting process. We have paying customers, a small engineering team, and a product already doing real work in production. The surface area is growing quickly, and we're looking for a senior engineer who can help us ship product while making the system more reliable, observable, and scalable.The RoleAs a Senior Software Engineer at Zero Hiring, you will work across our backend, AI interview systems, product workflows, and customer-facing features. You'll own important parts of the product infrastructure that customers may never see directly but depend on every day, including reliability, integrations, observability, data consistency, external API boundaries, and LLM-driven scoring quality.This is not a pure platform role. You will also ship product features alongside the rest of the team, balancing infrastructure improvements with direct customer value delivery.In your first 90 days, you would likely:Improve observability across backend services, interview flows, and AI scoring pipelinesHarden webhook and integration paths for idempotency, retries, race conditions, and partial failure scenariosBuild regression tests and evaluation workflows for AI scoring, rubric changes, and prompt updatesAdd timeouts, retry policies, and cost controls around external API callsShip several customer-facing features across employer and candidate workflowsLocationThis is a fully remote role. For this hire we are sourcing candidates based in Argentina, the Philippines, or Egypt only. As noted in the requirements below, you'll need at least four hours of daily overlap with US Eastern time.What We're Looking For:Required Qualifications:5+ years building production software, with strong backend experience in Python or similar languages, web frameworks, PostgreSQL, and async service designStrong product engineering instincts with the ability to move from a customer problem to a working production feature across API, database, integrations, and UIExperience with webhook-heavy, integration-heavy, or money-adjacent systems, with clear understanding of idempotency, replay safety, retries, race conditions, ordering, and recovery patternsPractical observability experience including structured logs, useful dashboards, tracing, alerting, and debugging production issues from evidenceFluency with LLM-backed product development, including prompt changes, structured outputs, regression tests, latency/cost tradeoffs, and failure modesHigh agency, strong testing judgment, clear communication skills, and at least four hours of overlap with US Eastern timeBased in Argentina, the Philippines, or EgyptBonus Qualifications:Experience with real-time voice, video, WebRTC, phone, or other latency-sensitive systemsExperience with recruiting, HR, ATS, CRM, or workflow automation productsExperience with billing, payments, subscriptions, credits, usage limits, or other revenue-critical systemsExperience building evals, regression harnesses, prompt versioning, or monitoring for LLM-powered featuresAgentic development workflows: you use Cursor, Claude Code, or similar tools as part of your real development loop and know where not to trust themHow We WorkWe are remote-first, small, fast-moving, and pragmatic. Engineers at Zero Hiring own production outcomes: shipping features, improving reliability, writing tests, watching the system after release, and making the product simpler where possible. We care about people who can handle ambiguity, communicate clearly, and make good technical decisions without turning every decision into a process.Compensation and BenefitsWe offer competitive salary for a senior engineer in your market. Equity is available for strong contributors who want meaningful ownership in what they help build.Our Hiring ProcessWe've designed our process to get you from application to offer in 2–3 weeks — no lengthy waiting periods, no unnecessary stages.Step 1 — AI Interview (within 48 hours of applying) Complete a short AI-powered interview at a time that suits you. No scheduling required — you choose when you do it, and it can be completed within 48 hours of applying.Step 2 — Interviews You'll meet the team. Typically 2–3 interviews, designed to give both parties a thorough and genuine sense of fit.Step 3 — Offer If it's a match, we move fast. Expect a clear, timely offer without the drawn-out back-and-forth.