Software Engineering Intern - Spring 2027

It’s 1813, and Humphrey Davy is dazzling London with scientific demonstrations and lectures. Soon enters the young bookbinder, Michael Faraday, dissatisfied with his own prospects and enamored by the mysteries of electricity. Faraday gets a break and gains an apprenticeship with Davy, and shortly thereafter (partially) blows himself and Davy up in a nitrogen trichloride explosion.

We think Davy’s sacrifice was worth it, though, since Faraday went on to do experimental work in the field of electromagnetism that is foundational to innumerable modern technologies. While we can’t promise you’ll become the next Faraday, we can promise you won’t be asked to deal with explosives on the job.

Instead, you’ll be receiving mentorship from experienced engineers, writing TypeScript and/or Haskell code, and contributing to a product that serves over 300,000 businesses. Check out demo.mercury.com to see our product for yourself.

As an Engineering Intern, you’ll join a team that aligns with your goals and interests. During the interview process, you’ll have the opportunity to talk through the various team openings. 

All Engineering Interns, regardless of the specific role, should:

• Be interested in continually honing their craft.
• Have curiosity and be willing to share their perspective.
• Appreciate quality in their work and that of others.
• Communicate well, and be able to write clear explanations of their reasoning on technical decisions.

Backend Engineering Interns should have experience using the Haskell programming language, or a strong desire to learn it, and have some familiarity with SQL. In this role you can expect to:

• Collaborate with data analysts to spec and build features that draw new customers to our product.
• Provide a backend to our mobile and web frontends, to do things like search transactions or send wire transfers.
• Build admin tools to increase the efficiency of day-to-day support operations, like identifying fraudulent customers or managing accounts.
• Integrate with third-party APIs, to do things like send checks or validate SWIFT codes.

Frontend Engineering Interns should have experience with the TypeScript programming language, and experience with React is a plus. In this role you can expect to:

• Work on a beautiful app: Since many of our customers are startups, they appreciate a well-implemented design. We have high standards for our UI, and we think it shows on our website. We encourage you to sign up and check out our onboarding experience, or read our blog post about our date picker.
• Push the limits of TypeScript: As a financial technology company, preventing errors is a top priority for us, and we take advantage of TypeScript’s advanced static typing features to prevent them.
• Work in an established codebase that still has room for growth. Across 650K lines of TypeScript, we’ve built abstractions and components that will give you leverage to build great features during your months at Mercury. But there’s still a lot more to build, be it optimizing the scrolling performance of a combobox, or building whole pages to deliver a feature to customers.
• Exercise ownership over the product: Our engineers work closely with our designers and contribute their own ideas to make the product better.

Full-stack Engineering Interns should have experience using the Haskell programming language, or a strong desire to learn it, some familiarity with SQL, and experience using the TypeScript programming language. In this role, you can expect to do a combination of the frontend and backend work that is described above.

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