Senior Software Engineer, Platform and Infra

Flex is building a finance super app for premium business owners — reimagining every single aspect of the financial workflow and financial services for any entrepreneur. The company has grown revenue 25x+ since publicly launching in September 2023 and is on track to achieve profitability by late 2025. Flex is focused on mid-market businesses ($3 - $100M revenue) that are largely overlooked by existing fintech solutions and reliant on slow and outdated regional banks.  We are targeting a ~$1T revenue opportunity that is largely up for grabs.

Flex is a fully remote company and this role can be performed from anywhere.

The Role

We are looking for engineers who are excited to be part of our early story and help us build a diverse and vibrant company. As a senior software engineer you will have the opportunity to work across the entire stack with a focus on the back-end. You will have the opportunity to learn and drive the creation of systems and tools for product teams to build upon. You should have a strong sense of ownership and enjoy taking projects from inception to release. As an early employee, you’ll be working with a nimble team of committed and talented engineers and having a large, long-term impact on technical design and engineering culture.

We are open to candidates from Canada, the United States, and Colombia.

• Ownership over foundational systems shared across a variety of different products.
• Play a critical role in the development, design, and maintenance of Flex's platform, services, infrastructure, and dev tooling.
• Own problems end-to-end, thinking through everything from api contracts, data, scalability, security, observability, and metrics.
• Lead by example and mentor engineers in all aspects of planning, development and testing.
• Be a catalyst for driving best-in-class technology frameworks and tooling while staying engaged with the latest technology trends.
• Be on call, with the expectation to ability to solve problems and find solutions for the servicing team

• Proficiency in NodeJS+Typescript and its ecosystem.
• An understanding of and interest in architectural patterns for highly available, scalable, low-latency, asynchronous systems
• Ability to hold yourself and the team to high standards.
• Strong communication (written and verbal) and interpersonal skills.
• Ability to provide in-depth evaluation of multiple technical directions and determine tradeoffs of each.
• Ability to make data-driven decisions on technical architecture and project prioritization.
• Exposure to modular monoliths along with the benefits and challenges they bring.
• Experience with any cloud based provider like Google Cloud, AWS, or Azure.
• Experience maintaining cloud-based infrastructure as code with tools like Terraform, Pulumi, or Cloudformation.
• Four or more years of relevant industry experience with a track record of shipping high-quality systems and platforms at scale.
• A strong work ethic

Interested?  We'd love to hear from you

At Flex, we value passion, determination, and honesty. Even if you don't fully match the job specifics, we encourage you to apply. Unusual career paths and unique skills can help you stand out. We believe diversity drives our success. Join us at [email protected]

Why Join Us

Flex is growing quickly — you’ll help shape the direction of a product and company with real momentum.

We’re well-capitalized with strong backing and a clear long-term vision.

You’ll work with a sharp, driven team that values autonomy, clarity, and quality.

Join ambitious builders who care deeply about winning together — and having fun while doing it.

Annual team on-sites. From Bogota to Mexico City, the entire Flex team gets together once a year to align and build camaraderie.