Senior Node & React Engineer — Equity & High-Impact POS

Simplex.; New York (NY); On-site; USD 180,000 - 220,000; Full time

Benefits offered by this job

Unlimited PTO

Full benefits package

Equity

Job summary

Simplex seeks a Senior Engineer in New York City to strengthen core platform services and user-facing features. The role emphasizes building with a long-term view, writing clean, scalable code, and delivering observable systems in a fintech-enabled environment.

You will work onsite in Flatiron, collaborate closely with product teams, and contribute to architecture decisions, CI/CD, and tooling, with equity opportunities for the right candidate.

Qualifications

• At least 5 years of software engineering experience.
• Strong CS foundation; familiarity with data-intensive architectures.
• Designs extensible APIs and abstractions for long-term maintainability.
• Excellent communication to translate product requirements into technical tasks.
• Hands-on with serverless architectures in cloud environments (e.g., AWS).

Responsibilities

• Build and own new user-facing features end-to-end, from data models to UI components.
• Improve observability: analytics, monitoring, and alerting across systems.
• Collaborate with product and engineering to architect differentiators including embedded fintech and AI agents.
• Develop CI/CD pipelines and developer tooling to increase development velocity.
• Shape engineering processes to support a world-class product.

Skills

Node.js

React

Next.js

TypeScript

AWS

Serverless

Tools

AWS

Terraform

Job description

Simplex seeks a Senior Engineer in New York City to strengthen core platform services and user-facing features. The role emphasizes building with a long-term view, writing clean, scalable code, and delivering observable systems in a fintech-enabled environment.

You will work onsite in Flatiron, collaborate closely with product teams, and contribute to architecture decisions, CI/CD, and tooling, with equity opportunities for the right candidate.