Fullstack Software Engineer

Insider, Inc.; Denver (CO); Hybrid; USD 100,000 - 130,000; Full time

Job summary

Insider, Inc. is looking for a Fullstack Software Engineer to join the team at Mural Pay in Denver. This role involves building critical financial infrastructure, working on core systems for global payments, and collaborating closely with the CTO to shape the product. Candidates should have a solid background in Node.js, React, TypeScript, and strong problem-solving skills in a startup environment. The successful candidate will thrive on challenges and prioritize code quality and correctness.

Qualifications

• At least 3 years of experience shipping production-grade web apps.
• Ability to work on both frontend and backend.
• Strong understanding of design principles.

Responsibilities

• Build core systems that power global payments.
• Collaborate with the CTO and other team members to shape the product.
• Establish patterns and standards for engineering practices.

Skills

Node.js

NestJS

React

TypeScript

HTML/CSS

GraphQL

Job description

Fullstack Software Engineer – Mural Pay

Location: New York, NY / Denver, CO

The Story

Every company is becoming a fintech. Mural is the global account layer that powers their financial stack.

Stablecoins have exploded from $28B to $300B over five years, with $30T+ in annual transaction volume — double Visa and Mastercard combined. The rails underpinning global money movement are being rebuilt from scratch. And we're the ones building them.

Our API makes this real and tangible: businesses use Mural to send, receive, and hold money across borders — faster, cheaper, and more reliably than anything that came before. But great infrastructure doesn't build itself. We need engineers who care as much about the elegance of the system as the outcome it enables.

What You'll Do

You’ll be joining a lean, high-intensity engineering team at an inflection point — processing hundreds of millions in volume today, with $1B+ projected in the next six months. You’ll work directly with our CTO and Head of Engineering, contributing full-stack from week one.

This role is about three things:

1. Building Infrastructure That Moves Money

You’ll work on the core systems that power global payments — state machines, transaction pipelines, reconciliation flows. Accuracy is non-negotiable when money is on the line, but so is the ability to build systems that adapt as the financial landscape evolves. You’ll own features end-to-end, think carefully about failure modes, and write code you’re proud to put your name on.

2. Shaping the Product

You’re not just implementing tickets. You’ll collaborate closely with our CTO, designers, and the broader team to evolve our API and platform — making complex financial workflows feel intuitive for the developers and businesses building on top of us. If you see a better way to design something, you’ll say so. If a tradeoff matters, you’ll surface it. We want engineers who think like owners.

3. Setting the Bar

As an early engineering hire, you’ll have an outsized influence on how we build — the patterns we establish, the standards we hold, the culture we cultivate. We believe quality engineering lives at the intersection of theory and experimentation: think rigorously, ship decisively. You’ll help define what that looks like in practice.

Who You Are

You’re a strong individual contributor who works well as a team. You don’t need someone looking over your shoulder. You take ownership of your work end-to-end, communicate honestly about timelines and constraints, and never let something fall through the cracks because it wasn’t technically "your problem."

You’re comfortable with the full stack. You have at least 3 years shipping production‑grade web apps using Node + NestJS (or something comparable) and React + TypeScript. You’re proficient with HTML/CSS and GraphQL, and you move fluidly between frontend and backend depending on what the problem requires. You care about design and have high standards for what you ship — not just whether it works, but whether it feels right.

You’re built for startups. You know what it means to operate in an environment with high ambiguity and real stakes. You move fast, make good decisions under uncertainty, and find energy in the challenge rather than frustration in the chaos. You’ve worked in a high‑growth environment before — or you’re deeply ready for one.

You’re obsessed with correctness and resilience. Moving money globally means the margin for error is low. You think carefully about edge cases, error handling, and what happens when things go wrong — because they will. You love a good state machine. You appreciate systems that are both robust and easy to reason about.

You’re curious about what we're building. You don’t need to be a crypto native, but you should be genuinely interested in stablecoins, global payments, and the financial infrastructure being rebuilt around them. The engineers who thrive here see the mission as part of the appeal — not just the tech stack.

What Success Looks Like

• You're shipping meaningful features from week one — contributing to our platform and API with minimal ramp‑up time

• The systems you build are reliable, readable, and maintainable — code that the team is proud of and that scales with us

• You've raised the bar — through the patterns you introduce, the reviews you give, and the standards you hold

• You've become a key voice on engineering decisions — someone our CTO and Head of Engineering rely on when it matters

Why Now

We're at an inflection point. The product is live. Customers are processing real volume. The capital is in. And landmark moments — the Genius Act enabling 3,500 U.S. banks to hold stablecoins, Stripe's $1.1B acquisition of Bridge — are validating exactly what we're building.

What we need now are engineers who want to be part of defining this category from the ground up. You’ll have real ownership, direct access to leadership, and a front‑row seat to what it looks like to build critical financial infrastructure at scale. The team is small and exceptional — from Palantir, McKinsey, DoorDash, Mercado Libre, Circle, and BlackRock — and we're only adding people who make it stronger.

If you want to build something that matters — this is the role.