Sr. Software Engineer (payments)

Mosaic.tech; San Francisco (CA); Hybrid; USD 170,000 - 215,000; Full time

Benefits offered by this job

Competitive salary

401(k) with 4% match

Early equity

Internet stipend

Learning stipend

Office set-up stipend

Insurance (medical, dental, and vision

HSA/FSA options

Life and disability insurance

Pet insurance

Flexible PTO

Paid national holidays

Global parental leave program

Promote from within

Lunch and learns

Team events and summits

Remote and hybrid opportunities

Flexible working hours

Weekly office lunches

Employee discount platform

Job summary

VGS is seeking a Sr. Software Engineer, Payments Quality, to champion quality across our Payments Engineering team.

You will own quality standards, build AI-assisted strategies, and implement end-to-end automated regression and load testing to safeguard a high-throughput payments platform. You will collaborate with feature teams, tech leads, and product management to ensure zero downtime and flawless accuracy, building emulators for external systems and advancing automated testing across the

Qualifications

• 5+ years of software engineering focusing on quality engineering, test automation, and performance testing for high-throughput distributed systems.
• Deep hands-on experience building automated test suites in Java, Python, Go, or TypeScript.
• Strong REST API testing and microservices validation.
• Experience embedding automated quality gates into CI/CD pipelines in cloud environments.
• Experience testing event-driven architectures (Kafka, SQS) and databases.
• Experience with AI-assisted test automation is a plus.

Responsibilities

• Define and embed overarching quality benchmarks for Payments Acceptance.
• Design and run high-concurrency load, stress, and latency tests.
• Develop AI-native QA tooling and emulator frameworks for external systems.
• Implement telemetry-driven test environments with Prometheus & Grafana.
• Mentor team members on quality engineering best practices and automate golden paths.

Skills

Quality engineering

Automation testing

Performance testing

CI/CD

Cloud-native tooling

Data & messaging validation

Python/Java/Go/TypeScript

Prometheus/Grafana

Kubernetes/Docker

Education

BA/BS in CS or related

Tools

JMeter

Locust

Gatling

k6

Job description

About VGS

VGS is building the trust infrastructure for a new era of commerce. As commerce becomes agentic, payments are increasing dramatically in volume, speed, and complexity, and the companies driving that shift need a foundation they can fully trust.

That's where VGS comes in. We're the world's leader in payment tokenization, trusted by the most innovative AI and Fortune 500 companies, merchants, banks, and fintechs to power modern payments and agentic commerce. We store more than 9 billion tokens and process more than 10 billion monthly interactions, touching a third of all e-commerce. That scale isn't incidental. It's why leading companies embed our universal token vault and credential management platform directly into their stack, taming the complexity of payment data so they can move faster.

Come build the platform that enables modern payments for the world's largest companies. We're helping businesses unlock new possibilities in an industry that never stops moving. And that takes exceptional people.

Trusted Engineering That Matters

Engineering at VGS

VGS is building the platform powering agentic commerce and global payments infrastructure. VGS Engineering is the pillar that supports that vision. We create a platform that is an indispensable, ubiquitous component of our partners' payments and security infrastructure. We build and operate high-scale, reliable, and resilient systems that manage mission-critical payment data across the globe. We don't just participate in the payments ecosystem; we power it.

Our Environment & Culture

• Modern Tooling as Leverage: We value speed and impact. To ensure nothing slows you down, we arm you with a highly consistent modern stack (e.g. AWS, Kubernetes, Java, TypeScript, Python) and world‑class AI‑augmented SDLC tooling. We strip away the friction so you can focus on the problems that demand creativity and judgment.

• Ownership of Outcomes: Scaling global payments infrastructure requires individuals who take personal ownership of outcomes from day one. We look for builders who combine high agency with deep strategic alignment; channeling their urgency and relentless iteration into what matters most.

• Mission‑Critical Accountability: We power payments infrastructure for global market leaders, making system trust and integrity our core deliverable. We don't treat compliance (PCI, SOC2, ISO27001), security patching, and platform maintenance as administrative overhead—we engineer them with first‑class product discipline. In payments infrastructure, reliability is not background work, it’s part of what customers buy.

Learn More: See how our engineering practices drive trust and innovation in our official blog and our reliability practices.

About the Role

As a Sr. Software Engineer, Payments Quality, you will serve as a key technical practitioner and quality champion on our Payments Engineering team. You will take ownership of setting, building, and enforcing world‑class quality standards across our core payment systems. In this role, you will write software for robust AI‑assisted quality strategies covering end‑to‑end automated regression suites and high‑concurrency performance and load testing.

Working closely with feature development engineers, Tech Leads, and Product Management, you will ensure our mission‑critical, high‑throughput payment platform and applications operate with zero downtime and flawless accuracy. Rather than relying on manual QA or traditional top‑down testing scripts, you will leverage AI‑native engineering methodologies and integrate test automation across the entire SDLC. You will also be building emulators for external systems, such as card networks and other partner integrations. We are looking for hands‑on builders who refuse to settle for the status quo, hate manual friction, and take immense pride in fortifying enterprise‑grade financial systems for scalability, reliability, and security.

What You'll Do

• Architect and Embed Quality Benchmarks: Own the overarching quality strategy for Payments Acceptance, building automated guardrails so seamlessly into our pipelines that rigorous end‑to‑end validation happens automatically, without slowing down feature teams, accelerating release cycles.

• Drive Performance & Stress Testing: Architect and execute high‑concurrency load, stress, and latency testing to stress‑test payment pipelines under extreme transaction volumes. You own the mission of ensuring our platform never drops transactions or degrades in latency during peak periods..

• Pioneer AI‑Native Software Engineering focused on Quality: Actively integrate AI‑assisted developer tools and agentic workflows into test creation, synthetic data generation, and automated edge‑case analysis to multiply testing velocity. Build high performance emulators for external systems.

• Deep Observability & Incident Prevention: Implement robust telemetry and telemetry‑driven test environments using tools like Prometheus and Grafana to monitor system behavior under load, driving blameless post‑mortems and proactive bug prevention.

• Cross‑Functional Velocity & Mentorship: Partner with feature teams to build "Golden Paths" for automated testing, ensuring engineers can validate code rapidly with high confidence. Mentor team members on quality engineering best practices.

What You Bring

• Ownership in Quality Engineering: 5+ years of software engineering experience focusing on quality engineering, test automation framework design, and performance testing for complex, high‑throughput distributed systems.

• Automation & Scripting Mastery: Deep hands‑on experience building automated test suites in Java, Python, Go, or TypeScript, with a strong command of REST API testing and microservices validation.

• Performance & Load Testing Depth: Proven track record designing and running performance, stress, and load tests at scale using tools like JMeter, Locust, Gatling, or k6.

• CI/CD & Cloud‑Native Toolchains: Direct experience embedding automated quality gates into modern CI/CD pipelines (GitHub Actions, GitOps) within containerized environments (Docker, Kubernetes/EKS) on public clouds (AWS).

• Data & Messaging Validation: Experience testing event‑driven architectures (Kafka, SQS) and relational/NoSQL databases, ensuring data consistency and transactional integrity under load.

• High‑Agency Mindset: An innate drive to eliminate manual friction, proactively seek out edge cases, and acquire whatever missing domain context is needed to solve complex quality challenges end‑to‑end.

Nice to Have:

• Experience with tokenization, payment processing, or security products

• BA/BS degree

• A knack for out‑of‑the‑box thinking that thrives in a fast‑paced startup environment

• Domain expertise in 3DS, Network Tokens, Account Updater, or payment gateway integrations.

• Experience with AI developer tools, LLM‑generated test automation pipelines, or synthetic test data generation.

• Practical knowledge of compliance and cloud security constraints (PCI‑DSS, SOC2).

170000 - 215000 USD a year

How We Work

At VGS, we embrace a remote‑first philosophy because we believe flexibility leads to great work and a healthy work‑life balance. That said, if you live within 30 miles of one of our office locations, you'll be on a hybrid schedule with some in‑person time, because we know there's real value in coming together.

We're not about being in the office every day. We are about connection, collaboration, and the energy that comes from a great brainstorm, a team lunch, or celebrating a big win in person.

Our Benefits

Financial and retirement

• Competitive salary

• 401(k) with a 4% match and immediate vesting (applies to US only)

• Early equity

• Internet stipend

• Learning stipend

• Office set‑up stipend (applies to US only)

Health and Wellness

• Insurance (medical, dental, and vision)

• HSA/FSA options

• Life and disability insurance

• Pet insurance

Vacation and time off

• Flexible PTO

• Paid national holidays

• Global parental leave program

Professional Development

• Promote from within

• Lunch and learns

• Team events and summits

Office life and perks

• Remote and hybrid opportunities

• Flexible working hours

• Weekly office lunches

• Employee discount platform

Equal Opportunity

We consider all applicants without regard to race, color, national origin, sex, age, religion, sexual orientation, gender identity, veteran status, marital status, physical or mental disability, or other protected classes under all applicable local, state, and federal laws and ordinances (AA/EOE/W/M/Vet/Disabled).

Qualified applicants with arrest and conviction records will be considered for this position in accordance with the San Francisco Fair Chance Ordinance.

Where We're Hiring

We are currently hiring in the following locations: Arizona, California, Colorado, Connecticut, Florida, Idaho, Illinois, Iowa, Michigan, Minnesota, New York, North Carolina, Ohio, Oregon, Pennsylvania, Texas, Utah, Virginia, Washington, Ontario (Canada), Alberta (Canada), and British Columbia (Canada).