Senior Backend Software Engineer Full Time NEW

Backpack is building the payment infrastructure for education. We’re a fintech company solving for the most complex – and most important – payment types that support students in their pursuit of their education; payments from 529 Plans, Scholarship Providers, Third-Party Payers and many more.

This is a $1.8TRN asset class with annual payment volume of $600B+ that has never had modern payment rails. Backpack is bringing these external payers online for the first time, with the opportunity to build the foundational infrastructure to be used for generations to come.

We already work with some of the largest and most prestogious universities in the country, including The University of Chicago, The University of Alabama, Arizona State University, Miami University and many more. We also work directly with scholarship providers, are lucky to work with large foundations like the Coca-Cola Foundation and Big Brothers Big Sisters.

We’re a small, high-output team backed by top investors. Every engineer here has a direct line to our customers, our product direction, and our architecture. If you want to build something that matters, at a pace that keeps you sharp, come join us!

The Role

We’re hiring a Senior Backend Engineer to own and evolve the core systems that power Backpack – our payment engine, platform APIs, and the infrastructure underneath it all. You’ll work directly with our founders and a tight engineering team to make critical technical decisions every week.

This isn’t a “take tickets off the board” role. You’ll shape what we build, how we build it, and how we scale it. We care about developer experience, and we want someone who has experience with (or genuine interest in) contributing to internal tooling that makes the whole team faster.

Here’s a glance at what the first 30, 60, 90 days could look like:

In the first 30 days, you’ll:

• Get your hands in the codebase and deploy to production in your first two weeks. We don’t believe in month-long onboarding — you’ll ship real code, fast.
• Squash bugs, write queries, and start building context on our payment engine, APIs, and infrastructure.
• Pair with engineers and sit in on product discussions to understand how decisions get made and where the biggest opportunities live.
• Take ownership of a small-to-medium backend project end to end — scope it, build it, ship it.

In the first 60 days, you’ll:

• Lead a medium-to-large project from technical design through production release, including writing a design doc, coordinating with product, and setting up monitoring/observability so you know it’s working.
• Start contributing to engineering standards — whether that’s improving our testing practices, tightening our CI/CD pipeline, or proposing architectural changes you’ve spotted.
• Participate in our CARE (Customer and Reliability Emphasis) month and contribute to reliability/infrastructure improvements.
• Write or improve an engineering doc. We’re a team that documents what we learn.

In the first 90 days, you’ll:

• Own a large, multi-phase project that touches multiple systems and potentially involves coordinating with other engineers. You’ll drive it from concept through launch and post-launch iteration.
• Have a clear point of view on where our backend architecture needs to go next — and start executing on it.
• Be a go-to voice in architectural discussions and help set the technical direction for scaling our payment infrastructure.

What We’re Looking For

You’ll thrive here if these describe how you already work:

• Builder mentality: Strong opinions, weakly held. You default to shipping the smallest thing that works, then iterate fast. You’d rather have something in production learning from real usage than a perfect design doc collecting comments.
• Ownership > tasks: You hate being blocked. When something is unclear or broken, you prototype, reach out directly, pair, or just ship a pragmatic solution. You don’t wait for someone else to fix what’s in front of you.
• Product-minded: You obsess over the “why” behind features. You dig into customer data and measure success in revenue and user love.
• AI-native: You already use Cursor, Claude, Junie, or similar every day. You treat AI as a pair programmer, not a novelty. You do not deliver “AI Slop”.
• Start-to-finish ownership: You don’t just launch a feature. It’s your baby – you implement monitoring, set up alerting, watch the metrics, and make sure it accomplishes what you set out to accomplish.
• User-first: Every product decision should be made with the end user in mind. You build products that are a pleasure to use.
• Growth-driven: You’re dedicated to your own growth and have the drive to continuously learn. You actively seek feedback and push yourself into uncomfortable territory.
• Customer-comfortable: You can talk to and work with customers of any kind – student families, university business offices, merchants – and put yourself in their shoes.

Your Experience

We recognize not everyone will meet all of the criteria. If you meet most of the criteria below and you’re excited about the opportunity and willing to learn, we’d love to hear from you.

• 7+ years of experience in software engineering with a strong background in backend development and product engineering. Minimum 2 years at a senior level.
• Expertise in JavaScript/TypeScript and Node.js (minimum 2 years of production-level experience). Experience with Ruby and Ruby on Rails is a plus.
• Advanced knowledge of Postgres and Redis.
• Experience scaling APIs and architecting/building backend systems for scale.
• Extensive experience with REST APIs. Experience with GraphQL is a plus.
• Experience shipping and operating ETL/background-job heavy systems in production.
• Experience with modern testing frameworks and practices including API testing.
• Experience in monitoring and observability and running a production application at scale.
• Experience managing and organizing multiple ongoing projects at once.
• Strong organizational and prioritization skills.
• Excellent communication skills and the ability to collaborate effectively within a remote team via tools like Slack, Notion, and Linear.
• Bonus: experience at Series A/B startups where you participated in scaling the engineering team and its practices.

Nice to Have’s

• Experience with authentication and authorization technologies (OAuth, JWT) or techniques such as SAML, SSO, etc.
• Knowledge of algorithms and protocols for securing data, including TLS/SSL, digital signatures, hashing, and encryption.
• Demonstrated success managing large-scale backend infrastructure and cloud infrastructure (AWS, Terraform, messaging queues, etc.) and CI/CD.
• Experience building applications from scratch.
• Domain knowledge in payment processing, identity/auth, or finance.
• Experience working in fintech, the financial services industry, or at early-stage startups.

Our Tech Stack

• Backend: Node.js, Postgres, Redis, Rails, Sidekiq
• Infrastructure: AWS, Docker, Terraform, CI/CD
• Front-end: TypeScript/JavaScript, React
• AI: Cursor and Claude, daily
• Security: AES-256 Encryption

Compensation and BenefitsSalary

The salary range for this role is $170,000 – $210,000

Equity

Competitive equity package

Benefits

• Medical, dental, and vision health care plans
• Health care FSA/HSA plans
• 401K
• PTO and 10+ public holidays
• Backpack Recharges — dedicated team time off to recharge

Location

New York City, NY or Austin, TX (Hybrid — in-office 3-5 days), or Remote.

Interview Process

We value transparency. Here is what you can expect:

1. Initial interview with the hiring manager or one of our co-founders (30-45 mins)
2. Second interview with one of our co-founders (CEO/COO) or Staff Engineers (30-45 mins)
3. Coding assessment — JavaScript/TypeScript + SQL (take-home or virtual, ~60 mins)
4. Virtual onsite (or in-person), including:

• Technical interviews (coding and system design)
• Meeting the rest of the Backpack team

1. Reference calls (we’ll ask for 2 references with at least one being a direct manager)

Accommodations

We are committed to providing an accessible interview process. If you need any accommodations at any point, please let us know and we’ll work with you.

We Look Forward to Hearing from You!

We cannot wait to hear from passionate, driven, and talented people who are excited about our mission. We’re building a first-of-its-kind fintech company to completely revolutionize an entire asset class and, eventually, how all Americans pay for their education. We acknowledge this is a big ask list – if there are a couple of missing pieces, we strongly urge you to still apply.