Software Engineer (Back End)

We’re seeking an experienced, senior back-end engineer to help develop the core platform surrounding our Workplace and TPA products. You’ll work across our Rails system of record, data connectivity layer, and major feature development - the platform that runs real 401(k) plans for advisors and their business owner clients.

What makes this role different from most Rails jobs: our platform is operated by both people and AI agents. The same APIs, actions, and workflows serve human users and the agents automating our administration work, so clean contracts, permissions, staging-before-commit patterns, and audit trails are product features, not afterthoughts. You’ll build the surfaces agents act through, along with the right guardrails for a complex fiduciary business.

You’ll join a small, tight-knit team in a flat hierarchy inspired by the Shape Up framework, participate fully from shaping through shipping, and report to our Director of Engineering.

What you’ll do

• Own major feature development end-to-end across our products, from design doc through deployment and monitoring.
• Build the tool surfaces our agents act through: typed, permissioned, logged actions against our system of record, with staging-and-promote patterns so nothing writes to a plan without a gate.
• Design and run our data connectivity layer: recordkeeper feeds, payroll providers, payments, and identity.
• Make auditability a priority so that every action, human or agent, is traceable, explainable, and regulator-ready.
• Lead architectural discussions, write design docs, and mentor through code review.

Our stack

• Ruby on Rails / PostgreSQL on AWS ECS
• React & TypeScript on the front-end
• Redshift + dbt + Metabase; PostHog for analytics
• Stripe, WorkOS, HubSpot, Customer.io
• Agno, Langfuse, Reducto, and Skyvern on the agent side

• 6+ years of professional software development experience.
• Deep expertise in Ruby/Rails: domain modeling, background jobs, API design, performance.
• Proven track record designing scalable APIs and data models - and strong instincts for permissions, idempotency, and auditability in systems that move real money.
• Proficient working with coding agents; we’re not hand-rolling boilerplate.
• Familiarity with AWS and infrastructure-as-code.
• Experience integrating third-party systems (payments, identity, CRM, payroll) and designing for their failure.
• Excellent communication skills and a collaborative mindset.

Nice to have

• Experience exposing systems to LLM agents (MCP, tool APIs), fintech or retirement domain, React/TypeScript for occasional full-stack work.

Build and operate the core Rails-based platform for workplace retirement and TPA products. Responsibilities include end-to-end feature development, scalable APIs and data models, agent-facing tools with permissions and audit trails, data integrations with payroll, payments, identity, and recordkeepers, architecture discussions, deployment, monitoring, and mentoring. The role requires strong Ruby/Rails expertise, AWS familiarity, third-party integration experience, and thoughtful design for reliability, compliance, and financial workflows. The summary above was generated by AI About Aboon

Setting up a 401(k) shouldn’t be the hardest thing a business ever does. But retirement plan administration is complex, fragmented, and manual, and it slows down both business owners and the financial advisors who serve them. Aboon was founded to change that.

We’re an AI-native platform and third-party administrator that makes it easy for financial advisors to find, win, and grow 401(k)s and other retirement products by pairing streamlined workflows with dedicated human service. Backed by leading investors including Bain Capital and Edward Jones Ventures, we bring decades of experience building for advisors and the retirement industry. We’re looking for exceptional, mission-driven people to build it with us., Compensation

The base salary range for this role is $210,000-$225,000, depending on experience, skills, and location. Total compensation also includes an annual bonus and equity., * Comprehensive health, dental, and vision insurance, with additional optional coverage

• 401(k) with company match
• Flexible paid time off and holidays
• 10 weeks paid parental leave
• A fully remote work environment, with all the technology and equipment you need
• Support for professional development and career growth