Staff Engineer, Trust & Vault

Yuno is the AI-native operating system of global commerce, powering the financial infrastructure of enterprise merchants, banks, and wallets. Through a single API, Yuno connects them to pay-ins, payouts, fraud prevention, KYC/KYB, and stablecoins globally, so they can operate everywhere. Agnostic by design and connected to 1,000+ payment methods and 460+ integrations in 190+ countries, Yuno optimizes acceptance rates, reduces costs, and strengthens security through specialized AI agents that learn from every transaction. Global brands including McDonald's, NetEase Games, GoFundMe, and Rappi run their payments on Yuno.

Yuno is looking for a Staff Engineer to be the senior technical leader for Trust & Vault — the domain that secures card data and optimizes how it's used across every transaction on the platform. You'll architect the foundational systems behind PCI-compliant card vaulting and tokenization, card authentication (3DS, network tokenization), and the optimization capabilities that lift authorization and acceptance rates, and raise the technical bar for the pod that builds them.

This is a hands-on leadership role in a zero-tolerance-for-failure environment. You'll design and build bank-grade, resilient capabilities, champion a "You Build It, You Run It" culture where your team owns its services from code to production, and turn the hardest problems in card-data security and payment optimization into elegant, maintainable architecture.

What This Domain Owns

• Card vaulting & tokenization — tokenize, store, and retrieve raw card data within the PCI boundary

• Authentication — 3DS / SCA and network tokenization to authenticate cardholders and strengthen every transaction

• Payment optimization — lift authorization and acceptance rates through network tokens, account updater, and intelligent use of vaulted data

• Account updater & portfolio migration — keep stored card credentials current to reduce declines, and migrate card portfolios between vaults and processors

How AI Shows Up in This Role

• The tokenization, authentication, and vaulting layer you own is foundational infrastructure for an AI-native platform — the secure card-data foundation every transaction, including agent-driven flows, depends on

• AI is our default execution layer: you're expected to use AI-assisted tooling fluently across design, implementation, testing, and review, and to shape how the domain adopts it

Your Contribution Will Be

• Domain architecture and technical leadership — own the architecture of Trust & Vault across vaulting, authentication, optimization, account updater, and portfolio migration; set the technical direction with versioned APIs and event-driven design, and raise the bar for the pod

• Card-data security and vaulting — architect the systems that tokenize, store, and retrieve raw card data within the PCI boundary, safely and at scale

• Authentication — build and evolve authentication capabilities (3DS/SCA, network tokenization) that strengthen transactions without adding friction

• Payment optimization — design capabilities that lift authorization and acceptance rates — network tokens, account updater, and smart use of vaulted data — turning secure card data into better payment outcomes

• Bank-grade, resilient systems — design headless, PCI-compliant capabilities engineered for a zero-tolerance-for-failure environment, where feature velocity never compromises reliability or compliance

• You Build It, You Run It — champion a YBIYRI culture: your team designs for multi-tenancy, elastic scaling, and automated observability, and owns its microservices in production

• Mentorship and cross-functional collaboration — mentor engineers and partner with Product, the CTO Office, and Staff Engineers across domains to eliminate silos and deliver complex, cross-team work

What Success Looks Like

Within your first 6–12 months, you've led the architecture of at least one core Trust & Vault capability (vaulting, authentication, or optimization), your pod owns its services in production under a YBIYRI model, and you're the technical voice Yuno trusts on card-data security, authentication, and PCI-compliant design.

Skills You Need

Minimum Qualifications

• Extensive software engineering experience, with deep expertise in Go and/or Kotlin (our core backend stack) and strength across the full stack

• A proven track record architecting robust, scalable, and maintainable distributed systems — event-driven platforms, APIs (gRPC/REST), and cloud-native or serverless architectures — with a strong grasp of design patterns and best practices

• Experience building foundational platform capabilities or complex distributed systems, ideally involving tokenization, card vaulting, authentication (3DS / network tokenization), or PCI-scoped infrastructure

• Strong experience with AWS and cloud-native services (RDS, ECS, EKS, S3, and similar)

• Excellent automated testing practices — unit, integration, and end-to-end — within Agile, DevSecOps, and CI/CD workflows

• Proven technical leadership — mentoring engineers, driving technical vision, and delivering complex, cross-team projects, with a feel for DORA metrics and unblocking teams

• A preference for clean, modular architecture over monolithic shortcuts, and the judgment to balance reliability and compliance against feature velocity

• English — advanced proficiency, written and spoken

Preferred Qualifications

• Domain expertise — PCI DSS card vaulting, tokenization and network tokenization standards, 3DS/SCA authentication, or account updater services from card networks

• Payment optimization — improving authorization and acceptance rates through tokenization, authentication, or credential lifecycle

• Experience in the payments or fintech industry, operating at global scale

• Performance optimization and efficient algorithms for high-throughput, low-latency systems

• Static analysis and code-quality tooling (e.g., SonarQube) and mature CI/CD pipelines

Nice to Have

• A track record of introducing new engineering practices or standards across multiple teams

• Open-source contributions or technical writing that raised the bar for others

• Spanish proficiency

Tech Stack

• Languages — Go and Kotlin (core), Java

• APIs — gRPC, REST

• Frameworks — Spring Boot, Spring WebFlux; Go standard library

• Messaging — Apache Kafka, SQS

• Databases — PostgreSQL, Redis

• Infrastructure — AWS, Kubernetes, Docker, Terraform

• Observability — Datadog, OpenTelemetry

• CI/CD — GitHub Actions, ArgoCD

• Version Control — Git / GitHub