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Senior Mobile Engineer

Slingshot AI

Slingshot AI

Software Engineering
New York, NY, USA
USD 150k-300k / year + Equity
Posted on Jul 22, 2025

Location

New York

Employment Type

Full time

Department

Engineering

Compensation

  • USTotal Comp (Cash + Equity) $150K – $300K • Offers Equity

We aim to pay 90th percentile for the industry. All roles including meaningful equity ownership.

Slingshot AI

Slingshot AI is the team behind Ash, the first AI designed for therapy. Our mission is to make mental healthcare more accessible and help people change their lives in the ways they want.

We’re building a world-class team by empowering individuals with the autonomy, flexibility, and support they need to do their best work. We dream big, iterate fast, and care deeply. If that sounds like you, we’d love to hear from you.

Our team spans machine learning, product, engineering, conversational design, clinical, growth, and operations, with offices in both New York City and London.

We're a well-funded Series A company, having raised $93M from Andreessen Horowitz, Radical Ventures, Forerunner Ventures, plus top-tier tech investors involved in ElevenLabs, Captions, Shopify, Plaid, Notion, Canva, Twitch, Airtable, and many others.

The role

This is a chance to join a passionate team leveraging cutting-edge AI to improve mental health access globally. As a Senior Mobile Engineer, you will play a critical role in building the user experience for our AI Therapy application, Ash. You will work closely with our ML team to implement new features, ranging from UX improvements to completely new AI-driven features. As a core member of a small but highly skilled team, we expect you to act as an owner and to care passionately about keeping building meaningful experiences for our end users.

Our tech stack uses Dart/Flutter for our apps, Kotlin for core backend services, Python for our ML work, as well as Rust for low level media streaming. We use gRPC and GCP (Kubernetes, Cloud Run) as our primary cloud provider. You’re not required to be an expert in all of these tools, but we would like you to come with a learning mindset and to not be afraid of getting your hands dirty with whatever tool the job might require.

About you:

  • Solid experience building and shipping mobile-first consumer apps using multi-platform frameworks. We use Flutter but we welcome backgrounds like React Native, Ionic, KMP, or both Swift and Kotlin.

  • Full-stack experience, developing backend endpoints for frontend features, interacting with databases, defining clear contracts, and maintaining a scalable and performant product. Some backend experience is critical.

  • User-centric and product-minded with a relentless focus on delivering exceptional user experiences and strong attention to detail in UX/UI.

  • Experience working in a fast paced environment, working at lightning speed to ship fast.

  • Self starter and a keen learner with an ability pick up new tools, languages, and concepts on the job. We don’t need you to be an Machine Learning Engineer, but having an interest in AI helps!

Key responsibilities:

  • Collaborate closely with our Product Manager and Designer to quickly design, build, and launch new features in our app, taking ownership of the whole stack.

  • Elevate user experience by continually refining app reliability, performance, and polish.

  • Rapidly investigate, diagnose, and resolve bugs to ensure product stability.

  • Taking initiative to independently prototype new features based on customer feedback and your own product intuitions.

  • While the mobile app will be your primary focus, we encourage everyone to be comfortable working in all parts of our stack, which includes the backend (Kotlin), internal tooling (Next.js/TypeScript), and ML scripts for evaluation, data processing, and model training (Python)

What we offer:

  • A chance to join a passionate tight-knit team working on something to change the world

  • Competitive compensation (we target 90th percentile)

  • Travel between our NYC / London offices

  • Usual startup perks like free lunch in our offices + generous learning budget

  • Generous budget to cover your personal therapy

Compensation Range: $150K - $300K