Senior iOS Engineer – Learning Experience (all genders

About Babbel Labs

Babbel Labs is building the future of language learning. We're an AI-first, independent company within the Babbel group, based in Berlin. Our teams bring AI, R&D and product together to ship experiences that set a new standard for how people learn.

Babbel is looking for a Senior iOS Engineer to help change the future of language learning within our Learning Experience teams.

This is an Individual Contributor role with team-level scope. You will work closely with product and engineering managers, designers, subject matter experts, and cross-platform engineers to build Babbel's core learning experiences — from the learning path and exercise player to real-time speaking and conversation practice.

You own the experience end to end: it ships as a distributable Swift package consumed by Babbel's main iOS app, and you follow it there — integration points, A/B experiments, rollout. And you'll do this the Labs way: AI coding agents are a first-class part of how we design, build, test, and review.

• Take part in all product development phases: discovery, prototyping, proposing solutions, implementing, reviewing, testing, and deploying learning experiences.
• Own the engineering side of our feature workflow: shape the PRD together with product, then pick it up — write the technical spec, agree Interface Contracts with backend and partner teams, slice the backlog, and build.
• Build quick prototypes to de-risk product ideas — the learnings feed the product, even when the code doesn't.
• Design and evolve the public API of our Swift package with deliberate versioning and breaking-change discipline — and land it in the main app: integration points, A/B experiments, rollout.
• Collaborate closely with product managers, designers, and other cross-functional teams to define and implement features that enhance how learners progress through their learning path, exercises, and speaking practice.
• Maintain and proactively improve the technology stack, build system, and the AI-agent conventions (skills, project rules, documentation) the whole team relies on.
• Share what you learn: technical documentation for core features, and knowledge actively passed on to colleagues.

• 5+ years of experience building scalable iOS applications using Swift.
• An AI-first mindset — a strong must for us. You have actively embraced AI coding tools in your own work — not just autocomplete, but directing agents through real feature work and critically reviewing what they produce — and you treat prompts, skills, and project conventions as engineering artifacts maintained like code. Deep experience with our specific agent stack isn't required — demonstrated adoption and genuine enthusiasm are.
• Strong, up to date Swift — including Swift 6 strict concurrency (actors, Sendable, isolation) and structured concurrency.
• Deep SwiftUI experience and a solid grounding in the Apple ecosystem and Human Interface Guidelines; you think in state-driven UI and know where the framework's sharp edges are.
• Strong opinions on state management and testable architecture — experience unidirectional-data-flow architecture, and willingness to go deep on ours.
• Testing as a first-class habit: deterministic, exhaustive unit tests with controlled dependencies, snapshot tests where the UI is the contract — not coverage theatre — and the CI/CD discipline to keep them green.
• Experience designing module boundaries, frameworks, or SDKs that other teams consume — ideally as distributable Swift packages — and the API-stability discipline that comes with it.
• Experience designing or consuming evolving JSON APIs and collaborating with contract-first backend teams.
• An eye for good architectural decisions based on feature requirements, and knowledge of how to balance technical debt against delivery speed.
• Comfort with ambiguity and fast iteration: directions evolve as we learn, and prototypes are a tool, not a deliverable.
• Clear, concise communication, an open mindset for feedback, and enjoyment in working closely with design and product in a lean environment.
• Fluency in written and spoken English.