Principal Engineer, Payments Infrastructure

Where We Are Today

8-figure ARR growing 100%+ YoY

Strong unit economics and efficient growth

Rapid merchant adoption and expanding market presence

Backed by experienced operators and investors with a history of building and scaling successful businesses

Why Now

This is a rare opportunity for a technical leader to step into a company with proven revenue, product-market fit, an established team, and a large market opportunity.

Three things make this an inflection point:

1. Product-market fit is established. Demand continues to grow, merchant adoption is accelerating, and Phoenix is outperforming expectations.

2. There is an opportunity to define a category. While many companies are building AI tools for commerce, few are focused on helping sophisticated DTC operators automate revenue-generating decisions at scale.

3. Our customers are AI-ready. They adopt technology quickly when it drives measurable business outcomes, creating an ideal environment for agentic products.

The Role

We are seeking a Principal Engineer, Payments Infrastructure to own the architecture and evolution of our core payments infrastructure across tokenization, wallets, processor integrations, routing, authorization, and reliability. This is a hands-on principal role on the payments pod, reporting to the CTO.

Phoenix moves real money for merchants who cannot afford a bad day. We run across multiple processors, gateways, and vaults (Adyen, Stripe, NMI, VGS, Spreedly), with card, wallet, and network-token credentials moving between them. Approval rate, dispute exposure, and processor health are numbers we actively manage, because each one lands directly in merchant revenue. We are building toward a platform where a merchant applies once and transacts across every rail underneath, without ever seeing the plumbing.

That is the system you will own. You have built payments infrastructure before, at a company whose product was payments: a vault integration you owned, a wallet migration you ran, an approval rate you moved, an incident you were on point for at two in the morning. You know how cryptograms and network tokens behave in production, and which credentials survive a move between providers and which quietly do not.

This role unifies the engineer and the PM. We are not hiring a product manager for payments; you are the product owner of this domain. You will sit on merchant calls, read the decline and dispute data yourself, decide what gets built and in what order, write the spec, ship it, and answer for the number it was meant to move. You will work directly with merchants and processor partners, and you will own outcomes rather than tickets. You are an AI power user who codes with agents daily and raises the ceiling of everyone around you through the code and design you put on the table.

What You'll Own

• Integration architecture. Evolve our processor, gateway, and vault integrations (Adyen, NMI, VGS, Spreedly, Stripe Connect) and partner checkouts, and bring new rails on, keeping behavior consistent, observable, and testable no matter which one a transaction takes.
• Product direction for payments. Discovery through rollout. You talk to merchants, mine the decline and dispute data for what to build next, and make the call on what not to build. Roadmap, spec, code, and the metric afterward are all yours.
• The merchant-facing surface, not just the pipes. Routing, salvage, and MID health only matter if a merchant can see and act on them. You design what surfaces in their dashboard and their agent (a projected threshold breach, a proposed routing change, a one-click fix), and you own making payments setup something a merchant can get through without a support ticket. Today it is the single biggest barrier to going live.
• Tokenization, end to end. Vaulting, wallets, and network tokens: the full credential lifecycle from capture through provisioning, storage, transaction, update, and expiry. Cryptograms, network transaction IDs, DPAN and MPAN, and the PCI scope boundaries around all of it.
• Payment method portability. Moving stored credentials between providers and vaults without asking a shopper to re-enter anything, wallets especially. Apple Pay and Google Pay provisioning, domain verification, per-provider wallet configuration, and the limitations of each provider on what can be migrated.
• Approval rates. Treat authorization as a revenue system. Decline taxonomy and salvage, retry and cascading logic, 3DS, BIN and routing strategy, card updater, and the instrumentation to prove a change moved the number.
• Dispute and fraud infrastructure. Own the ingestion, normalization, and operational use of disputes, chargebacks, fraud notifications, and card-brand monitoring data across processors. Build the systems that keep merchants and MIDs clear of thresholds and make those signals available to routing, authorization, and forecasting.
• Mission-critical reliability. SLOs, telemetry, on-call, and incident response for payment paths that cannot fail quietly. Idempotency, reconciliation against processor settlement, and the discipline to find a money bug before a merchant does.
• The engineering bar. Clean, well-tested, documented code; ADRs / RFCs; and an operationalized agentic SDLC that raises the whole team's velocity and quality, on a platform under continuous PCI assessment where review evidence matters.

What We're Looking For

Required
• 10+ years building and shipping production software, with principal-level impact as a hands-on engineer who still writes application code today.
• Product judgment, proven. You have decided what to build, not just built what was decided: a feature you conceived from direct customer evidence and shipped end to end, a pricing or packaging call you made, or something you killed and why. "Partnered with product" is not this. You can sit in front of a merchant or processor partner and explain a trade-off in terms they act on.
• You know the end user firsthand. You have watched the people who use your systems actually work (merchants, ops teams, support), and you changed what you built because of it. You can name a specific thing a user did that surprised you and what you shipped in response.
• Deep payments experience at a payments company: a PSP, gateway, vault, orchestration layer, or platform whose core product was moving money.
• Tokenization and wallets. Hands-on work with a token vault, and production ownership of Apple Pay and Google Pay: provisioning, merchant configuration, and domain verification. You can reason about cryptograms, network tokens, network transaction IDs, and PCI scope from first principles.
• Payment method portability. You have migrated stored credentials and wallet tokens between providers, vaults, or processors, and you know where the limits are.
• Multi-processor integration. You have integrated and operated against more than one acquirer, gateway, or PSP concurrently, including routing or cascading between them.
• Authorization and approval-rate work. Decline analysis, retry strategy, 3DS, and demonstrated ownership of an approval-rate number you improved.
• Disputes and fraud-monitoring exposure. Chargeback flow and representment, plus the layer above it: alerts and deflection, TC40 / SAFE fraud reporting, and card-brand monitoring programs such as VAMP and the Mastercard equivalents.
• Money-movement fundamentals. Idempotent payment operations, ledger or system-of-record design, and reconciliation against processor settlement.
• Incident ownership. You have been the person on point when payments broke in production: detection, containment, merchant communication, and cleaning up the financial damage afterwards.
• Genuine AI power user. You code with AI every day, using Claude Code or an equivalent agentic setup, a dialed-in environment, and real leverage.
• Commercial fluency and strong communication. You can sit in front of a merchant or a processor partner and explain a technical trade-off in terms they act on. ADRs / RFCs, and a track record of raising the engineering bar for everyone around you.
Preferred
• Built or operated a payment orchestration layer or multi-PayFac platform, where a merchant applies once and transacts across several rails underneath.
• High-risk or direct response merchant portfolios, where dispute exposure and MID health are daily concerns.
• Subscription and recurring billing at scale: rebills, MIT credential chaining, card updater, and involuntary churn recovery.
• Alternative payment methods and BNPL integrations (Klarna, Affirm, PayPal, and similar).
• PCI DSS v4 assessment experience as an engineer.

Leadership Traits We Value

High ownership

Decisiveness

Strong recruiting and talent development capabilities

Accountability

Product judgment

Calm under pressure

Builder mentality

Culture

These are the values that guide how we operate:

All In to Win — Operate with urgency, intensity, and a relentless bar for excellence. 

A Players Only — Only hire, develop, and keep A players. Protect talent density. 

Merchant First — Merchants are why we exist. Every decision measured by merchant impact. 

Entrepreneurial Spirit — Move like a Day One company. Fast, scrappy, hungry. Everyone owns. 

Execution Over Ego — Best ideas win regardless of source. Status and titles do not matter.