Senior Full Stack Engineer II (Contract)
We're putting together a talented team to build the #1 training platform for Runners
We help everyday runners become outstanding by building an incredible app providing world-class training, coaching and community for everyone, whether you're improving your 5k time or training for your first marathon.
We’re growing extremely fast! In November 2023 we closed a $6.5M funding round led by JamJar with participation from Eka Ventures, Venrex and Creator Ventures. In 2024, we were selected by Apple as one of three global finalists for the iPhone app of the year, reflecting the innovation and impact of what we’ve built & in 2025 we were acquired by Strava !
Our ambition is huge: to become the go-to global leading training platform for millions of runners everywhere. We’re growing with purpose and looking for people who want to build something meaningful with lasting impact. With the recent acquisition by Strava accelerating our journey, now is a really magical time to join.
About the contract role
We are looking for talented, creative and positive team players for our highly-skilled cross-functional engineering group on a contract basis. This role will collaborate closely with our modelling teams to integrate features that are core to Runna’s mission (think adapting plans around holidays and B races, supporting new cutting edge plans, and building in-app experiences around our AI/ML tooling).
This will be a 6-month contract role.
What you’ll be doing
Architecting, building, testing and delivering new features across the full stack
Working with the Product team to identify the most suitable solution for the best customer experience
Collaborating with modelling/AI engineers to design architecture used to interface between the Runna training engine and Runna app
Always be on hand to help when help is needed on technical matters
Coaching and supporting engineers, providing guidance, mentorship, and code reviews without creating bottlenecks.
Contribute to us operate more efficiently, by building and maintaining our developer tooling and CI/CD pipeline
We rotate the responsibility of releases across engineers, so you will get the opportunity to lead the process and deploy changes to production
Impacting engineering by championing new technologies and setting standards for engineering quality
What you’ll bring to the team:
Very proficient in TypeScript/JavaScript development
Able to work in a highly skilled engineering team in a fast-paced, iterative environment. In 2024 we shipped:
99 mobile app releases (iOS and Android)
443 API releases
237 modelling backend releases
4+ years experience in your main expertise area (Frontend, Backend etc)
Comfortable picking up new things and working on technologies outside your comfort zone
Are skilled in delivering features end-to-end, from architecture design and building through to releasing, testing and supporting
Enthusiasm for our ways of working which include:
Iterative development, continuous deployment and test automation
Knowledge sharing, pair programming, collaborative design & development
Shared code ownership & cross-functional teams
Have experience with React Native (worked on large scale applications)
Have experience with AWS
Are experienced in delivering features full-stack
Bonus points if you have:
Are experienced in SwiftUI
Are experienced in deployment, releasing cycles or CI/CD
Have experience with Serverless architectures
Experience with Terraform or other IaC tooling (e.g. CDK, CloudFormation, etc.)
Have experience in open source contributions, including reporting bugs/issues in GitHub, testing new releases, or contributing to code
Our Tech Stack
Below you can find a small reflection of our current tech stack:
Frontend:
React Native (iOS and Android)
Typescript
GraphQL (Apollo Client)
Fastlane
SwiftUI (Apple Watch)
Maestro E2E tests
Backend:
Serverless (AWS)
Lambdas (NodeJS & Python)
AWS AppSync
DynamoDB, S3, SQS, SNS, EventBridge, SageMaker
Snowflake
All the other good stuff:
Sentry
GitHub Actions
Intercom, Mixpanel
RevenueCat
App Store Connect / Play Store
Google Tag Manager
Our Interview Process:
Our aim is to keep the interview process as straightforward and enjoyable as possible, and will consist of the following stages:
Screening call with Talent team (30 minute video call)
Getting to Know You + Live Coding (45-minute video call, first 25 mins will be an introductory chat followed by two live coding exercises from )
1.5-hour technical interview (the first half of the call will be used to discuss the take-home technical task from the previous stage and the second half will consist of system design and some general architecture/tech questions)
Please let us know if there’s anything we can do to better accommodate you throughout the interview process - this can be from scheduling interviews around childcare commitments to accessibility requirements. We want you to show your best self in the process, so please speak to your Talent Partner
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