Senior Software Engineer
Shape the architecture. Set the bar.
Confidential · AI Fintech Platform · San Francisco, CA · On-Site 5 Days/Week
This company is an AI-driven accounts receivable platform designed to help enterprises automate invoicing, cash application, and collections — improving efficiency, reducing errors, and accelerating revenue cycles. The platform automates invoice creation and distribution, enhances collections with AI-powered reminders and predictive payment insights, and seamlessly integrates with ERP and accounting systems.
Founded by an elite team with top-tier academic backgrounds. Backed by two leading venture firms with a fresh Series A close. One of the fastest-moving hiring teams on the market.
Serious Backing. Serious Domain.
Accounts receivable is one of the most manual, neglected functions in business — and this platform is replacing it with software that actually works. Enterprise clients trust it for invoice accuracy, uptime, and revenue cycle speed. The team is small, the problem is massive, and the backers are among the best in the world.
High-Stakes Domain: Correctness & Uptime Matter
This is fintech / AR automation. The work is consequential — enterprise clients rely on this platform for accurate invoicing and cash flow. You'll be building systems where correctness is non-negotiable and reliability is the standard.
First Senior Engineering Hire
You'll shape the architecture, set the engineering bar, and define what great looks like as the team scales. This is not an IC role in a large org.
Direct Founder Collaboration
You'll collaborate directly with the founders on product direction and technical trade-offs from day one — not filtered through layers of management.
Real Ownership, Real Autonomy
Significant ownership over what gets built and how. Schema design, migrations, system design reviews, runbooks — the full technical scope is yours.
Proven Traction + Top Backers
Top-tier VC-backed with $22M+ raised. Enterprise customers live. The foundation is solid — now it's time to build the technical org that scales it.
We are looking for a Senior Software Engineer with 5+ years of experience to be the first senior engineering hire at this company — shaping architecture, shipping end-to-end features, and setting the bar for engineering quality as the team scales.
You'll have significant ownership over what gets built and how, collaborating directly with founders on product direction and technical trade-offs. If you thrive with autonomy and want to build the technical foundation of a fast-growing product, this is your role.
"You will be the first senior engineering hire — shaping architecture, owning the full stack, and setting the engineering bar as the team scales. Direct collaboration with founders on product direction from day one."
- Design and build full-stack features across the Next.js frontend and backend API layer
- Lead end-to-end schema design, migrations, and backfills across Prisma and MySQL — designing rollouts that are safe to deploy in a high-stakes fintech environment
- Set the bar for engineering practices through system design reviews, incident response, runbooks, and observability
- Mentor other engineers through code review and architectural guidance — you are raising the floor for the whole team
- Collaborate directly with founders on product direction and technical trade-offs that will define the platform for years
- 5+ years of experience in full-stack software engineering
- Experience in big tech — FAANG or faster (e.g. Databricks, Square) — or VC-backed startups, early-stage preferred
- Experience at an early-stage startup (sub-30 people)
- Scaled a B2B SaaS product from early users to meaningful ARR
- Strong full-stack development skills including proficiency in TypeScript
- Proficient with Node.js, Next.js, React, Vercel, or Prisma
- Proficient with event-driven tools like Inngest or Temporal
- Track record mentoring engineers via code review and design reviews
- Degree from a top-20 CS program
- Needs direction or defined scope to be productive — this role demands self-driven ownership
- Only worked on large teams with narrow ownership — this is not a ticket-taker role
- Prefers backend-only or frontend-only work — full-stack ownership is required
Recruiter Screen (AIONIA)
20–30 minutes covering background, motivation, and what you're looking for in your next role.
Technical Interview
Deep-dive on full-stack experience, system design, engineering quality bar, and how you've mentored teams.
Take-Home / Coding Exercise
Practical assessment of full-stack skills relevant to the platform — designed to be fair and focused.
Founder Round
Direct conversation with the founders on product direction, technical trade-offs, and cultural fit. Fast process — they move quickly.