Software Engineer II

Remote; San Francisco (CA); Remote; USD 120,000 - 180,000; Full time

Job summary

Flex is building a finance super app for premium business owners, operating as a fully remote company. We’re looking for a Software Engineer II to power financial services features, including payments and credit, with a focus on reliable, maintainable code inside a regulated environment.

You’ll own medium-sized features end-to-end, collaborate with engineers and product teammates, and ship frequently (production three to five times per week).

Qualifications

• Have strong fundamentals in software development and ability to work effectively within established systems
• Product sense—you think about the user impact and business value of your work
• Ability to take responsibility for the maintenance and quality of what you build
• Experience with financial services, regulated industries, or handling sensitive data is a plus but not required
• Ability to research and proactively solve problems, bring solutions to the table
• English proficiency
• A strong work ethic

Responsibilities

• Own the full lifecycle of medium-sized features and tasks across our product stack
• Build user-facing features, internal tools, APIs, and backend services
• Write clear, maintainable, and tested code that you'll be responsible for long-term
• Participate in code reviews and provide timely feedback to teammates
• Build features with the end product and user in mind, not just the code
• Reason carefully about how your work extends in service of larger product needs
• Build upon systems and features that others depend on
• Balance speed with reliability and compliance in a regulated environment
• Collaborate with other engineers and product team members to deliver high-impact work

Job description

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businesses ($3 - $100M revenue) that are largely overlooked by existing fintech solutions and reliant on slow and outdated regional banks.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.

About the Role

We're looking for a Software Engineer II to help build product features that power financial services. You'll work on systems that handle payments, credit, and other core products that our customers rely on daily to drive business operations.

What You’ll Do

• Own the full lifecycle of medium-sized features and tasks across our product stack

• Build user-facing features, internal tools, APIs, and backend services

• Write clear, maintainable, and tested code that you'll be responsible for long-term

• Participate in code reviews and provide timely feedback to teammates

• Build features with the end product and user in mind, not just the code

• Reason carefully about how your work extends in service of larger product needs

• Build upon systems and features that others depend on

• Balance speed with reliability and compliance in a regulated environment

• Collaborate with other engineers and product team members to deliver high-impact work

What Makes You a Great Fit

• Have strong fundamentals in software development and ability to work effectively within established systems

• Product sense—you think about the user impact and business value of your work

• Ability to take responsibility for the maintenance and quality of what you build

• Experience with financial services, regulated industries, or handling sensitive data is a plus but not required

• Ability to research and proactively solve problems, bring solutions to the table

• English proficiency

• A strong work ethic

Technical environment: We primarily use Typescript, PostgreSQL, and GCP. We are building in a monorepo with a lean towards rapid value creation through trunk based development. Deploying to production 3-5 times a week is the average velocity of a team member.

What matters to us: We value ownership, product sense, and clear communication. You should be someone who thinks beyond just shipping code to understanding the impact on users and the business. We're a small team, so everyone wears multiple hats and jumps in where needed.

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.