Founding Engineer

Our mission

Commercial credit is a $3+ trillion market in the US — and almost none of it has been automated.

There are 33 million small and mid-sized businesses in the United States. Almost all of them run on credit. And the way banks decide who gets it hasn't meaningfully changed since the 1980s — a spreadsheet, a stack of PDFs, a 60-day wait, and a decision that often comes back "no" for reasons nobody can articulate. Banks are running on bloated operations teams, losing deals and working with antiquated software that works half the time.

We're building autonomous lending agents that fix this — the infrastructure for how commercial credit gets issued, and how our economy grows.

Who we are

Proximitty (YC W26) is building autonomous commercial lending teams for the largest banks and fintechs in the US. We're backed by top investors — Y Combinator, CRV, Cohen Circle, and Uphonest, with angels leading teams at Stripe and OpenAI. We’re growing rapidly and on track to hit 7-fig ARR by end of year.

Our founding team:

Wye Yew (CEO) advised banks at McKinsey on commercial lending and credit risk and previously led Growth at Taptap Send ($75M -> $200M ARR in 12 months). He was the first Malaysian to place in the Top 3 in the World Mathematics Championships in 2018.

Zi (CTO) built the world's first MCP gateway at ACI.dev (4k+ Github stars in 3 weeks), and prior to that led Bloomberg's core security infrastructure, which powers 300K+ terminals today. He previously received the National Scholarship of China.

You’ll be working alongside founders who’ve led fintechs to Series D and shipped at scale on agent infrastructure problems most teams haven’t earned the chance to solve yet — self-evolving & self-healing agents, software factory, and large scale evals. If we get this right, millions of businesses currently ignored by banks get access to the credit they should already have and we’ll be building the most powerful tool banks have seen.

What you'll own and drive

As our first founding engineer, you’ll work directly with the founders on frontier applied-AI problems: long-horizon reasoning over years of complex financial data, reliable computer-use agents in brittle legacy systems, and evaluation infrastructure for high-stakes decisions where correctness is partly factual, partly judgment. In your first 6–12 months, you will:

• Build out the core infrastructure for one of the smartest lending systems ever shipped
• Own the product end to end — architecture, agents, evals, UI/UX
• Collison install/deploy with customers — fly to banks, sit with credit officers, watch them use what you built, and iterate on the flight home
• Create self-evolving agents and a software factory that improves with every iteration and automatically hill climbs on evals

We're looking for..

• You deeply understand the importance of security, reliability, and auditability of shipping AI agents for banks, fintechs, and regulated financial institutions.
• You are constantly up to date with frontier agentic architecture, techniques, harnesses, and self-evolving infrastructure.
• You have a strong desire to own a product end to end: building it, deploying it, talking to customers, selling it, learning from it.
• You can hold your own with a 60-year-old banker — curious, respectful, and genuinely interested in what they know.
• You're comfortable with change. Early stage means rolling up your sleeves and staying flexible as the company, product, and priorities evolve. Learn and unlearn.
• You know that polish only matters when it serves real users. You don’t over-engineer, prematurely optimize, or reach for complexity just because you can. What matters most is the value we deliver. Just because you have a hammer, doesn’t mean everything is a nail.

Our tech stack

TypeScript, Next.js, Mastra, Postgres, AWS, Inngest, and more. In the age of AI, we think the tool preferences of coding agents are way more important than that of humans.

Our culture

• Fitness, health, and wellbeing first. Engineers who are physically wrecked build worse companies. Train, sleep, eat well.
• High trust, low overhead. No standups. No status updates. No "quick syncs." You'll be trusted to own your work end to end. If you need help, ask. If you don't, we won't invent a reason to check in.
• Be ready to do a bit of everything. There's no wall between engineering and go-to-market. Everyone talks to customers. Everyone sees the pipeline. Everyone owns a piece of a pitch at some point.
• Stay close to the customer. Empathy for the banks and officers we serve. Obsess over solving their actual problem — not the one we imagined.
• Pragmatism over perfection. We'll never be perfect, but we can always ship something, gather feedback, iterate, and improve. Experimentation is the default.
• No ego. Embrace feedback. Admit mistakes quickly. Celebrate team wins over individual ones.
• Direct. We'd rather have an awkward five-minute conversation than a polite six-month misalignment.

Benefits

• 1-2% equity
• $120–200K salary
• Full medical, dental, vision insurance
• All meals (lunch, dinner) fully expensed
• Gym and wellness stipend
• All customer travel fully covered

Logistics

• In-person at our offices in San Francisco
• Expect to fly ~2x a month to meet and deploy with clients
• We work intensely — but training, health, and sleep always come first

Interview Process

1. A 30-minute conversation with both cofounders
2. A 3-day work trial (fully paid, flights + accommodation included)
3. Offer.