Principal Architect – Product Engineering

About Cari

The Cari Network is building a blockchain-based payment system powering real-time, 24/7 movement of digital money across the traditional finance and digital asset ecosystems. A pre-launch startup, we're creating an entirely new category of financial infrastructure that brings cash on chain through tokenization while powering the full spectrum of payments for our network - banks and most importantly, the customers they serve.

About the Role

Reporting to the VP of Engineering, Banking, you will be the hands-on architect for everything Cari's banks and their customers touch: our bank-facing API platform, our operations dashboard, our white-labeled wallet interface, and the domain services behind them. You will lead our architecture practice-chairing the RFC process and design review and making architecture decisions within agreed guardrails-while writing production code alongside the team.

This role requires fintech or banking experience. You will have built money-movement, payments, or banking platforms that operate at scale under regulatory, security, and bank due-diligence scrutiny, and you know how banks actually integrate, reconcile, and operate.

Cari serves two very different audiences, and you will architect for both:

• B2B - bank API platform. Banks integrate server-to-server. That demands strict, versioned contracts, mutual TLS, API key lifecycle, signed webhooks, idempotent money movement, per-bank isolation and fairness, and Sandbox-to-Production parity.

• B2B2C - white-labeled wallet. A wallet that banks offer to their own retail customers, delivered either as internet-facing multi-tenant SaaS or deployed inside the bank. That demands tenant isolation, per-bank branding and custom domains, bank-to-Cari identity handoff, and secure embedding on end user devices.

Underneath both is one shared ledger that spans deposit balances held at a bank and on-chain tokens recorded on the Network's blockchain, so correctness, security, and operability are not optional.

What You'll Do

• Write production code for most sprints. Build critical paths yourself, create reference implementations, and review the changes that matter most across TypeScript/Node.js services and React front ends. You will own at least one product capability and ship in it.

• Own the architecture of a scalable banking platform. Define service boundaries, API contracts, data models, and tenancy patterns that let Cari onboard many banks and their customers without re-architecting.

• Lead the RFC process and design review. Decide within agreed guardrails, escalate cross-Cari team and bank-contract decisions, keep durable decisions documented, and keep material technical debt visible and tracked.

• Own the bank API contract (B2B). Versioning, idempotency and exactly-once semantics on token transactions, webhook delivery guarantees, rate limiting and fairness across banks, and environment parity.

• Own the wallet architecture across deployment models (B2B2C). Multi-tenant SaaS and on-premises packaging, bank identity integration , tenant isolation, and secure embedding (content security policy, cross-window messaging).

• Design for ledger integrity end to end. Transaction state machines, failure handling, and reconciliation and drift detection between off- and on-chain balances.

• Turn non-functional requirements into built systems. Set measurable targets for resilience, performance, disaster recovery, and security, and deliver them in partnership with Cari Engineering.

• Be the technical counterpart for banks. Lead architecture walkthroughs, security questionnaires, and due-diligence reviews, and define integration patterns for core banking systems and digital banking platforms.

• Lead secure development. Threat modeling, penetration-test remediation, product-layer SOC 2 evidence, and software supply-chain controls in CI.

• Raise the bar. Mentor principal and senior engineers, and set standards for AI-assisted development and the guardrails around it.

What Success Looks Like in Year One

• The multi-tenant wallet SaaS is live with tenant isolation that passes bank security review.

• The bank API has a versioned contract with documented idempotency and webhook guarantees that match actual behavior.

• Critical ledger-integrity and resilience requirements are closed with evidence.

• The RFC and design review process runs predictably under your leadership.

• The platform onboards new banks without bespoke re-architecture.

Qualifications

• Fintech or banking is required: 12+ years building production systems, with significant time on payments, money movement, core or digital banking, or other regulated financial platforms.

• Required hands-on production experience with: Kafka (event-driven architecture), Restate (durable execution and workflows), Redis, AWS EKS, and Terraform.

• 3+ years as a hands-on architect or principal engineer, with a record of designing platforms that scaled across many institutional customers.

• Shipped both a partner-facing API platform (B2B) and a white-labeled or embedded customer-facing product delivered through partners (B2B2C, multi-tenant).

• Deep TypeScript/Node.js and PostgreSQL; comfortable reviewing and unblocking React work.

• Strong command of money-movement correctness: idempotency, sagas and outbox patterns, state machines, ledgers, and reconciliation.

• API and identity security: OAuth 2.0/OIDC, mutual TLS, API key and secret rotation, signed webhooks, and OWASP practices.

• Experience with bank vendor due diligence, SOC 2, or similar regulatory and security scrutiny.

• Designs for operability: instrumentation, failure modes, and runbooks.

• Clear written communication; RFCs and bank-facing architecture documents are core to the job.

Nice to Haves

• Fiat payment rails: ACH, wires, RTP, FedNow.

• Integrations with core banking or digital banking platforms.

• Blockchain experience not required but a strong bonus-tokenized deposits, stablecoins, custody providers such as Fireblocks, EVM/zkSync, or Solidity.

• Embedded SDKs, iframe or web-component delivery, and white-label theming.

• Experience leading an architecture practice at an early-stage fintech through scale.

Our Stack

Node.js 24, TypeScript, Fastify, PostgreSQL (Aurora), Kafka, Restate, Redis, React 19 / Vite, AWS EKS, Terraform and Helm, Auth0, Fireblocks, Foundry.

What This Role is Not

• Not a people-manager role-this is a senior individual contributor position.

• Not production infrastructure, SRE, or on-call ownership-those sit with our Platform Engineering team, whom you will partner with closely.

What We Offer

• Competitive base salary, bonus, and equity

• Full medical, vision, dental benefits

• 401(k) with company matching

• Flexible PTO in a remote-first environment

• Opportunity to shape a market-defining protocol with an experienced founding team

Security Responsibilities

Applies to all Cari employees

• Comply with all Cari information security policies, including the Acceptable Use Policy, and complete required security awareness training.

• Protect the confidentiality, integrity, and availability of Cari systems and data, including bank-partner and customer information, consistent with least-privilege access principles.