Senior Fullstack Engineer – Fintech Real-Time Payments

Nium; San Francisco (CA); Hybrid; USD 120,000 - 160,000; Full time

Benefits offered by this job

Competitive compensation

Equity opportunities

Learning stipend

Hybrid work model

Job summary

Nium in San Francisco is seeking a skilled frontend engineer to build and scale our real-time payments platform. You will own features from concept to customer delivery, using React, TypeScript, and Next.js within a modern microservices environment.

You will work on REST APIs and backend integrations with Java Spring Boot or Node.js, while ensuring performance, accessibility, and robust testing. The role supports a flexible hybrid work setup with strong collaboration across global teams.

Qualifications

• 4 years of experience building web applications in production environments.
• Experience with large-scale systems.
• Background in Fintech or global payment systems preferable.

Responsibilities

• Help evolve rapid prototyping to foster innovation and quick market validation.
• Own the full application stack from discovery to customer revenue cycle.
• Be a self-starter and work independently with guidance from mentors and management.
• Learn technologies quickly and adapt to changing requirements.
• Build user-facing features using React, TypeScript, and Next.js.
• Develop and integrate REST APIs using Java Spring Boot or Node.js.
• Maintain clean, modular, well-tested code across the stack.
• Contribute to architectural decisions, code reviews, and shared components.
• Optimize for performance, accessibility, and responsiveness.

Skills

React

TypeScript

Next.js

Java

Spring Boot

Node.js

REST APIs

Docker

CI/CD

HTML/CSS

Tools

Docker

EKS

Grafana

ArgoCD

Flagsmith

LaunchDarkly

Job description

Nium in San Francisco is seeking a skilled frontend engineer to build and scale our real-time payments platform. You will own features from concept to customer delivery, using React, TypeScript, and Next.js within a modern microservices environment.

You will work on REST APIs and backend integrations with Java Spring Boot or Node.js, while ensuring performance, accessibility, and robust testing. The role supports a flexible hybrid work setup with strong collaboration across global teams.