Backend Software Engineer

About three+one

three+one® provides liquidity and treasury solutions to public entities, including municipalities, counties, school districts, authorities, higher education institutions (public and private), and nonprofit organizations. We serve as a liquidity data partner that helps simplify cash, banking, and investment decisions so our clients can confidently maximize the value of their cash. Our technology and partnership empowers entities to make data-driven financial decisions. We uncover new sources of income and savings for entities looking to innovate and identify new resources for our clients by identifying all cash as a revenue-generating asset. On average, our work leads to 30% more earnings and 73% more cash being invested confidently. Our core services include:

●      cashVest®, a platform for liquidity monitoring and forecasting,

●      rfpPrep®, a digital tool to streamline banking and investment procurement, and

●      muniBank, a banking fee benchmarking solution. Additional tools are currently in development.

Role Summary

We're seeking a driven Backend Software Engineer to help grow one of the nation's fastest-growing public sector fintech firms. As a Software Engineer, you'll be instrumental in building and scaling the platform infrastructure that helps public entities across the country make smarter, more confident financial decisions. This role is ideal for a self-motivated, goal-oriented individual who enjoys working with data-intensive applications, and is looking to grow into more advanced system design and architectural responsibilities over time.

This position with report to the Chief Product and Technology Officer and will be fully remote. Travel is expected to be up to 5%.

Responsibilities

As a Software Engineer, you will support:

Backend Development 

• Design, build, and maintain scalable APIs and backend services.
• Work with financial and transactional data pipelines, ensuring accuracy and performance.
• Improve system reliability, observability, and performance.

Full-Stack Contribution 

• Contribute to front-end features using React when needed.
• Collaborate with designers and product to deliver cohesive user experiences.
• Help connect backend systems to intuitive, performant UI components.

Feature Development & Delivery

• Own features from design through deployment with guidance from senior engineers.
• Translate product requirements into technical implementations.
• Write clean, maintainable, and well-tested code.

Collaboration & Code Quality

• Participate in code reviews and technical discussions.
• Work closely with product, design, and other engineers.
• Contribute to improving development workflows and standards.

Data & Systems Thinking

• Work with structured financial datasets and time-series data.
• Ensure correctness, consistency, and auditability of backend logic.

Qualifications

• Bachelors degree plus minimum five years work experience.
• Minimum 3–5 years of relevant and progressive software engineering experience.
• Demonstrated proficiency in Python.
• Proven ability to build and maintain APIs.
• Familiar with React, modern JavaScript/TypeScript, and the ability to contribute to UI features.
• Experience with relational databases and version control (Git), CI/CD workflows.
• Exposure to cloud platforms (AWS, GCP, or similar) and containerization basics.

Additional Skills and Abilities

• Experience in FinTech, banking, or financial systems.
• Familiarity with data processing or ETL workflows.
• Exposure to infrastructure-as-code tools.
• Experience working with analytics or reporting systems.
• Exceptional attention to detail, time management, and the ability to manage multiple priorities independently.
• Growth-oriented mindset with the ability to accept and act on feedback constructively.
• Eager to learn, results-driven, and adaptable.

Application Timeline

We anticipate the application window for this opening will close on: June 5th, 2026. Submission does not guarantee selection, and three+one reserves the right to modify or cancel the hiring process at any time. 

Only shortlisted candidates will be contacted. We’ll retain all applications for future consideration.

Selected candidates will be asked to participate in a technical coding exercise as part of the interview process to demonstrate technical proficiency and reasoning.

Benefits Overview

At three+one, we invest in our team’s health, well-being, and growth - offering competitive pay and a flexible benefits package that supports employees and their families at every stage.

Full-time Employment Opportunities include:

●      Competitive salary and benefits (Health, Dental, Vision, Basic Life, SDBL)

●      401K Plan

●      Flexible PTO, sick leave, and paid holidays

●      Cell phone reimbursement

Benefits offerings may vary by location and employment status.

Equal Opportunity & Fair Chance Hiring

three+one is an Equal Opportunity Employer. We consider all qualified applicants without regard to race, color, religion, sex, national origin, disability, veteran status, or any other characteristic protected by applicable law.

Qualified applicants with arrest or conviction records will be considered in accordance with applicable laws, including the California Fair Chance Act.

ADA Accommodation Statement
three+one is committed to providing reasonable accommodations throughout the hiring process. If you require an accommodation, please indicate this in your application or reach out through our general contact form.

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