Senior Software Engineer I - Ruby on Rails with Sidekiq

Elsevier•Philadelphia, PA

1d•$86,600 - $173,300

About The Position

Wellsheet is a clinical decision support platform used by more than 20,000 providers across 100+ hospitals. We embed directly in the EHR (Epic, Cerner, Athena) and put AI-generated clinical context in front of clinicians at the bedside. In 2026 Wellsheet became part of Elsevier's Clinical Solutions group, and we're now building the next generation of our product: a new clinical AI experience shipping to our first hospital clients in early 2027, backed by an integration platform we've run in production for years. We're a small, all-senior engineering team. You'll own real surface area from your first weeks, work directly with the people who built the system, and ship software that clinicians use during patient care. No healthcare background is required. We train the clinical and interoperability domain; we hire for engineering judgment. The Platform squad runs the machinery underneath everything clinicians see: real-time EHR sync across Epic, Cerner, and Athena, FHIR ingestion for 100+ hospitals, and vocabulary normalization across 125+ clinical terminologies. The squad is led directly by the technical leader behind Wellsheet's platform. Its next major build, which you'll help kick off, is the platform API that other Elsevier clinical products and internal teams will consume. The squad also owns the internal tooling for managing the platform and the health of the stack itself, from framework upgrades to developer tooling. Our stack today is Ruby on Rails with Sidekiq on AWS (ECS, Aurora PostgreSQL), with a TypeScript frontend where our tools need one. The work is mostly backend, but internal tools need real interfaces, and this squad builds its own. We don't require prior experience in any of the stack. You will build the platform API alongside the squad lead: own endpoints, contracts, and the extraction work that turns internal seams into a real interface. You will also be building the internal tooling for managing the platform, frontends included: vocabulary mapping, data quality, hospital onboarding, and the operational views that let a small team run 100+hospitals

Requirements

Current development skills with Ruby on Rails with Sidekiq on AWS (ECS, Aurora PostgreSQL), with a TypeScript frontend.
Possess backend fundamentals: queues, retries, transactions, and the failure modes between them.
Have real depth in SQL and relational data modeling, and the instinct to check the query plan.
Possess End-to-end ownership of production systems, including the unglamorous parts.
Have a debugging temperament: patient, methodical, happy in logs.
AI-assisted development as a default: coding agents and spec-driven development are already part of how you work

Responsibilities

Owning platform subsystems end to end: ingestion pipelines, sync reliability, normalization.
Keeping the stack healthy: major framework and dependency upgrades, developer tooling, and the CI that keeps a small team fast.
Taking of loosely specified problems ("this vendor's FHIR implementation does something strange under load") through diagnosis, design, and durable fixes.
Keeping correctness and observability strong as the platform takes on new consumers.
Pair with the engineer who built our sync and normalization systems and take ownership of one production pipeline, including its on-call. Your first shipped work will be a piece of the platform API or the internal tooling around it. By month three you'll own a platform surface that other teams depend on.