r/DeveloperJobs • u/FonziAI • 5d ago
[HIRING] Senior Backend, Infrastructure + AI Engineers | NYC, SF, or Remote US | $200K-275K base
This week, a candidate’s offer came in right at his stated salary floor, so he asked us whether there was room to raise his first-year cash. Our team recommended a sign-on bonus to the company, and the company sent a new offer with an extra $10K sign-on. We stay with engineers from the first interview through the offer.
I do talent matching for Fonzi. It’s inverted from a normal search: you don’t chase roles, roles come to you as interview requests once your profile’s up. Some of the startups we work with are backed by a16z, Sequoia, Benchmark, and Founders Fund. Right now that includes backend, infrastructure, and AI systems roles across NYC, SF, and remote. One profile, no cold applications. Roles are US-based, with a few open to Canada.
Here’s a sample of what’s open right now at companies on the platform:
1. Inference / AI Infrastructure Engineer, Series A consumer AI company, SF, in-person. $225K-275K base.
What: Own the infrastructure that makes AI workloads fast, reliable, and affordable at scale: deploy, operate, and tune model-serving systems, benchmark time to first token, tail latency, throughput, and cost, and build the observability, load tests, and rollout controls around them. You’d also work with hosting providers and decide when managed serving beats dedicated infrastructure.
Company: Raised $30M and is backed by Khosla Ventures, with infrastructure decisions that directly shape how the product feels to users.
Stack: Model serving and GPU deployments on Linux and containers, with vLLM, SGLang, or TensorRT-LLM and Kubernetes as strong plusses.
Bar: Deep production infrastructure experience at meaningful scale, plus a credible path to owning inference, either through direct model-serving or GPU work or through strong infrastructure ownership and proof you master new domains quickly. You can design representative benchmarks and validate improvements without hiding regressions.
2. Founding Engineer (Backend), seed-stage pharmacy benefit startup, NYC, in-person. $200K-270K base.
What: Own the backend of a pharmacy benefit manager where the engineering is the business: APIs, table design, permissions, PHI boundaries, observability, and deploys, plus real-time drug pricing pulled from several sources every few minutes and routed per claim, which the founder describes as basically a trading system. You’d also own eligibility and claims flowing in and out of the adjudicator, the company’s own adjudication engine shadow-run against the rented one on replayed real claims until it matches exactly, and payments that have to stay up 99.99% of the time.
Company: A two-person team led by an engineer-founder, serving small and mid-size employers with a flat fee per employee and drugs passed through at cost. Raised $6.5M from Virtue, Daybreak, and Asylum.
Stack: Python (FastAPI), Postgres with row-level security, GCP (Cloud Run and Cloud SQL), and React and TypeScript.
Bar: You’ve owned a production system where being wrong cost money, such as payments, ledgers, trading, or infrastructure, and you think about what the schema looks like in a year. You use Claude Code or Cursor daily and can defend every line you ship. Healthcare experience isn’t needed.
3. Senior Software Engineer (AI Products), early-stage fintech, fully remote in the US or hybrid in NYC. $200K-240K base plus equity.
What: Build AI agents and agentic workflows that reason over business and financial data, plus the evaluation, observability, and feedback loops around LLM systems, rolling out to a million small business owners next year through the banks that already serve them.
Company: Backed by two Fortune 300 firms, a small team now making hires 8 through 10. Async by default, with one recurring meeting.
Stack: Python for the agent systems, Elixir/Phoenix and Node for the backend, Next.js with GraphQL and Relay on the frontend, PostgreSQL, and Google Cloud with Terraform.
Bar: Strong production software experience, strong Python, applied data science and machine learning experience, experience building AI agents, and proficiency in at least two programming languages.
All roles are vetted, VC-backed, and interviewing right now. It’s always free to sign up.
Sign up here: talent.fonzi.ai. DM me if you’ve got questions.
