Senior Full-stack Developer (.NET)

Modeshift builds the software platform that runs public transport for 60+ cities across Europe and the US. Our platform covers contactless fare collection, real-time vehicle tracking, passenger mobile apps, operator tools, and the back-office systems behind them. From checking an arrival time to tapping to board, passengers interact with Modeshift-powered systems throughout the journey.

We’re hiring a Senior Full-stack Engineer to own features end-to-end across that platform.

What you’d work on

You’ll work on the backend for a connected system of many devices – vending machines, POS terminals, validators, board computers, info panels, and more – and on software that runs onboard the vehicles. Recent and upcoming work includes:

•  Payment processing for contactless fare collection, including tap-on/tap-off pay-as-you-go and fare capping
•  Real-time data pipelines feeding passenger apps and third parties like Google Maps
•  Multi-tenant APIs that transit agencies and their integration partners depend on
•  Back-office and operations tooling for the people running transit day to day

You’d own a feature from design through to rollout, including the parts nobody likes owning.

Our stack

.NET / C# on Azure Service Fabric, React with TypeScript, MS-SQL, and the rest of the Azure platform. Continuous delivery, every PR reviewed, automation wherever we can get away with it.

What we look for

•  7+ years building production backend services in .NET
•  Comfortable taking a feature from API design through to the React UI without handing it off
•  Distributed systems experience that’s hands-on, not inherited
•  Deep database knowledge: schema design, query performance, indexing strategy, how things behave under load
•  Strong opinions about API design, testability, and what shipping means
•  AI coding tools are part of how you work. We use Claude and other frontier tools daily, and if that doesn’t excite you, you won’t like it here.

We value multidisciplinary engineers. If you’ve worked seriously in other ecosystems – whether Kotlin, Android, iOS, embedded, anything outside the .NET world – that counts for a lot here. The problems we solve cross stacks, and engineers who’ve crossed them before tend to do well.

Bonus: payments, real-time data systems, or multi-tenant SaaS.

We’ve been hiring slowly because most CVs don’t match the role’s requirements. If yours does, you’ll hear back quickly.

How we work

Hybrid in Sofia, with flexibility week to week. Decisions are made by whoever is closest to the problem.

Compensation and benefits

•  Performance bonus
•  Premium private health insurance
•  Hybrid work, home or office
•  Personal assistant for your car
•  MultiSport or equivalent
•  Clear ownership, direct access to decision-makers, and real product impact

Interview process

Short screening call first. If that goes well, one technical interview covering backend design, APIs, databases, distributed systems, and React/TypeScript tradeoffs, plus system thinking and algorithms (general across our developer roles). The final round is with the team and focuses on ownership, communication, and how you work. We aim to close within two to three weeks of the first call.

About Modeshift

A transit technology company building the systems that make public transport work, growing across the EU and US.