Full Stack Engineer

Company DescriptionA-Comm is building the trust infrastructure layer for AI-powered commerce. As AI agents increasingly mediate purchases, discovering products, comparing options, and completing transactions on behalf of consumers, there is no standard for capturing and verifying the evidence trail of what happened and why. We're solving that.We created the A-Comm Evidence Protocol (AEP), an open protocol (Apache 2.0) that does for agentic commerce what HTTPS did for the consumer web. Our hosted platform, A-Comm Vault, captures cryptographically immutable evidence chains across e-commerce and agentic transactions, from discovery through fulfillment, giving merchants, payment networks, and regulators a verifiable record of every transaction.Where we are today:AEP protocol shipped and publishedA-Comm Vault builtFull agent response pipeline shipped (automated evidence gathering, confidence scoring, Stripe submission)Active onboarding into two sandbox environments being 1) with a leading payment network and 2) a Government innovation departmentPartnerships in flight with a leading PSP, +$20M annual revenue merchant, and fintech network design partnersBacked by: angel investors including Simon Taylor (fintech investor via AngelList), with additional angels from SoFi, Visa, and Plaid. Advisory bench includes Mike Lemberger (former CRO and EU CPO, Visa) and Tom Purves (former Head of Visa Checkout).We are a small, high-conviction team going after a structural layer of agentic commerce. This is an early-stage role with outsized ownership and equity.Role DescriptionThis is a full-time role for a Senior Full-Stack Engineer. You will work directly with the founder and Fractional CTO to own and extend the A-Comm Vault platform across the full stack: cryptographic evidence capture, API development, platform integrations, and partner & customer-facing dashboard surfaces.This is not a "build features from a ticket queue" role. You will be a technical co-builder making architecture decisions, shipping production code daily, engaging with partner engineering teams, and helping recruit and mentor a junior engineer behind you. You'll work in the codebase from day one alongside Claude Code (our AI-assisted engineering workflow), with direct exposure to payment network sandbox programs and regulatory engagements.What you'll work on:Extend the A-Comm Vault engine: capture pipes, evidence chain integrity, transaction-type modulesBuild and ship solutions with and alongside our merchant customersDevelop API endpoints for AEP, platform webhooks, and merchant onboardingContribute to sandbox deliverablesOwn infrastructure: PostgreSQL, Redis, BullMQ job queues, cryptographic signing and verificationBuild dashboard components (Next.js/React) when needed. This is full-stack, not backend-onlyQualificationsRequired:5+ years of professional software engineering experienceStrong TypeScript proficiency across the full stack (Node.js backend + React/Next.js frontend)Experience with relational databases (PostgreSQL preferred) and query builders or ORMsComfortable with API design and implementation (REST; we use Fastify)Experience with async job processing (BullMQ, Bull, Celery, Sidekiq, or equivalent)Experience with cryptographic primitives (hashing, digital signatures, key management) or immutable data structuresDemonstrated ability to own and ship production features independently, not just contribute to themStrong debugging instincts and comfort working in a codebase you didn't writeNote: we've built 80% of the needed infrastructure needed over the last few months with code reviews and testing, so you're not walking into a dumpster fire of vibe coded tech debtStrongly preferred:Payments, fintech, or commerce infrastructure backgroundExperience with Claude Code, Codex, Antigravity, or OpenClawFamiliarity with e-comm app development (Admin API, webhooks, Remix/Polaris)Experience with compliance engineering (PCI-DSS, SOC2, data privacy)Startup experience — you've been employee #1-10 before and know what that meansNot required:A shiny CS degree. Nice to have, but we care about what you can build, not where you studied.What We OfferMeaningful equity — this is a foundational engineering hire, compensated accordinglyDirect access to payment network executives, regulatory sandboxes, and fintech investorsFull remote flexibility with travel covered when in-person collaboration is neededHealth insurance and benefits (details finalized at offer stage)A codebase that's already substantial and well-architected — not a blank repo and a pitch deck