JUNIOR FULL STACK ENGINEER

Rational Exponent is looking for early-career engineers who are serious about shipping and already using AI tooling as a core part of how they work.

THE ROLE

You will work as a full-stack engineer on the core Reagent product, embedded in a small delivery team alongside a product representative, tech lead, DevOps, and QA. Your job is to take stories from refinement to “done” — end-to-end, across the full stack, with ownership of the full lifecycle.

We work in thin vertical slices. That means getting to working, demonstrable software as fast as possible — not building layers and assembling them at the end. If you instinctively want to prove E2E integration first and defer the edge cases, you’ll thrive here.

We use AI tooling — Claude Code and others — as a primary development workflow, not an occasional assistant. This is non-negotiable. If AI tooling is not already part of how you work day-to-day, this is not the right role.

YOUR FIRST FEW MONTHS

We structure onboarding to set you up to own stories independently as quickly as possible:

• Weeks 1–2: Buddy with an experienced engineer — observe, contribute, understand the codebase and delivery rhythm
• Weeks 3–6: Co-own stories — you drive, your buddy guides
• Week 7+: Solo story ownership — you take a story from refinement to “done” with the team around you if you need them

This is a ramp, not a probation. We invest in making it work.

WHAT YOU’LL LOVE

• Genuinely hard problems: trust, governance, and evaluation of AI in regulated industries — a space most companies aren’t solving yet
• A team small enough that your work is visible and your opinions shape direction
• An AI-native environment where good use of tooling multiplies your impact — you will move faster here than anywhere else
• A structured ramp to real ownership, not months of ticket-grinding on someone else’s code

WHAT TO EXPECT

• Everyone owns the delivery outcome. You will be supported, but the expectation is that you drive your stories to “done” and keep things moving
• The backlog moves fast, and delivery cadence is continuous
• This is a genuinely full-stack role. We expect contribution across frontend and backend — AI tooling has made this more achievable than ever, and we invest in helping engineers grow across the stack
• You will be learning on the job. We expect that — and we expect you to come ready to learn fast

WHAT WE’RE LOOKING FOR

• AI-native development workflow. You already use AI tooling to move faster, and you know how to structure your work to get the best out of it. Show us your workflow — this is the first thing we assess
• Strong Python and React/TypeScript fundamentals. You have the core building blocks. Years of experience matter less than whether the fundamentals are solid
• Thin-slice thinking. You can decompose a problem into the smallest thing that proves end-to-end integration. You don’t instinctively defer the hard bits to a later phase
• Delivery instinct. We don’t need a long track record — but we want to hear examples of things you finished. Side projects, coursework, contributions where you took something to “done” on your own initiative
• Testing awareness. You understand why tests need to reflect real system behaviour, not just return green lights. You are ready to develop this into a genuine discipline
• Clear, proactive async communicator. We are 100% remote. Silence is a blocker. You surface issues early, keep the team informed without being prompted, and communicate with enough clarity that your intent is never in doubt in a Jira comment or Teams message
• Coachable and direct. You take feedback well, implement it fast, and ask questions rather than staying stuck

TECH STACK

This is what we build with. You don’t need to know all of it — strong Python and React/TypeScript are the starting point, and you will grow into the rest:

Core foundations: Python and React/TypeScript are essential starting points.

Our stack: Python, FastAPI, LangChain, LlamaIndex, MLflow, Svelte/SvelteKit/TypeScript, MongoDB, Qdrant, Kubernetes, Terraform, AWS (EKS, Lambda, S3, Bedrock), Azure Cognitive Services, REST, GraphQL, OpenAI and HuggingFace APIs.

Our frontend is built in Svelte/SvelteKit. Strong React/TypeScript engineers pick it up quickly — AI tooling makes the transition straightforward.

ABOUT RATIONAL EXPONENT

Rational Exponent is a new company with an experienced team with a track record of successfully building, scaling, and exiting enterprise software and services companies with a particular focus on finance, banking, capital markets, healthcare, and other highly regulated industries. Our mission is to provide the tools and controls that will allow complex, regulated entities to confidently deploy applications based on state-of-the-art foundation model AI. We develop systems and frameworks to allow our customers to create trustworthy cognitive applications that control risks, evidence compliance, and deliver business value.

COMPREHENSIVE BENEFITS THAT SUPPORT YOU AND YOUR FAMILY

We provide a competitive benefits package designed to support your health, financial future, and work-life balance including multiple national medical, dental (with a $0 employee option), and vision plans with company premium contributions, tax-advantaged accounts such as an HSA, Healthcare FSA, and Dependent Care FSA, and life and disability coverage, all within a flexible, remote-first work environment.