Software Engineer - Mercury Command

Description

In 1965, a Scottish engineer was asked to solve a routine job with a hard catch: banks wanted to close on Saturdays but still serve customers, and no one had a sound way to confirm who the real user was. James Goodfellow, at Smiths Industries, saw that a check needed two things: something you hold, such as a card, and something you know, such as a PIN. His proposed PIN had 6 digits, but he was told people could only remember 4, so the design changed. Over 60 years later, more than 3 million ATMs still use a card with a 4 digit PIN.

The company's Command is an LLM-powered financial assistant, released to all customers in June 2026. Users can ask about their finances and act on them in plain language, whether that means checking cash flow, sending payments, issuing cards or managing invoices. The product is live, so the job is to improve it, add capabilities and find new ways to use LLMs for a stronger banking experience. A public demo is available for anyone curious about the product.

Responsibilities

• Build new capabilities that users want to keep using.
• Take ownership of the product and push for it, helping to design and release new Command skills.
• Work with product and compliance colleagues to agree what correct behaviour means for each new capability, then write the tests that verify it.
• Join a small team of experienced product and AI engineers shaping the company's future.
• The list above is only a sample, since Command is changing and priorities will move as the team learns. You should be fine with uncertainty in a scrappy startup.

Requirements

• 1 to 4 years of backend or full-stack development experience.
• Knowledge of Haskell, React, TypeScript and Redux, or real eagerness to learn them.
• Experience building products powered by LLMs.
• A hands-on builder with a strong product mindset and a record of shipping new products.
• You understand users' needs and can turn that view into products they enjoy.
• You can weigh trade-offs and come up with creative ways to reach goals.
• You use AI tools in your daily work and want them to multiply your impact, whether by speeding up development, raising code quality or solving hard problems in new ways.

Conditions

The role is in a scrappy startup environment where priorities can change quickly.

Benefits

• Total rewards include base salary, equity (stock options or RSUs) and benefits.
• Pay ranges are competitive within SaaS and fintech and are refreshed regularly using up-to-date compensation survey data.
• Offers depend on experience, expertise, geographic location and internal pay equity compared with peers.
• Target base salary for US employees, in any location: $122,400 to $176,000 USD.
• Target base salary for Canadian employees, in any location: $115,700 to $166,399 CAD.