Sierra · 1 day ago
Software Engineer, Mobile
San Francisco, CA
Full-time
Onsite
Senior Level
$230K/yr - $390K/yr
6+ years expSierra is creating a platform to enhance customer experiences through AI, primarily operating from San Francisco. They are seeking a Software Engineer focused on mobile development to lead the architecture and implementation of their Experience SDKs for iOS and Android, ensuring a seamless integration of chat and voice agents into mobile applications.
Artificial Intelligence (AI)Enterprise SoftwareSaaS
Responsibilities
Own the mobile Experience SDKs for iOS and Android. Lead the architecture, implementation, and evolution of our native SDKs that embed Sierra chat and voice agents into customer apps. Make them a joy to integrate for other engineers and a delight to use for end users
Deepen OS-level integrations and interactions. Push into platform-native capabilities: notifications, background execution, voice and audio routing, app extensions, system share sheets, in-app attachments, deep links, and other operating-system surfaces that make agents feel truly “at home” on each platform
Design and ship best-in-class mobile interfaces. Work hand-in-hand with our design team to translate Figma concepts into fluid, responsive mobile experiences. Sweat the details on motion, gesture handling, transitions, and accessibility so the agent feels fast, natural, and trustworthy on every device
Create a robust SDK developer experience. Define clear APIs, documentation, and sample apps that make it simple for customer engineering teams to integrate Sierra. Focus on stability, versioning, upgrade paths, and metrics so that our mobile surfaces are as reliable as they are beautiful
Collaborate tightly with web frontend and product teams. Partner with our React/TypeScript frontend engineers to keep interactions, visual language, and behavior coherent across web and mobile. Work closely with product and PMM to bring new agent features to mobile in a way that feels native to each platform
Champion quality, performance, and craftsmanship. Set the bar for mobile engineering quality at Sierra: smooth animations, low latency, resilient offline behavior, and thoughtful error states. Instrument and profile the experience, then iterate to keep it fast and reliable at scale
Work across the stack when needed. While your center of gravity will be Swift and/or Kotlin, you’ll occasionally dip into backend services (Go, GraphQL) or frontend code to unblock features or fine-tune end-to-end flows, working with the broader Product Engineering team
Qualification
Required
Deep mobile engineering expertise. Significant experience (typically 6–10+ years) building high-quality native mobile apps or SDKs on iOS (Swift) and/or Android (Kotlin). You've shipped production code used by large numbers of users and have the scars and judgment that come with that
Strong SDK and API design instincts. You've built or maintained SDKs, libraries, or shared frameworks before. You care about clean API surfaces, versioning, and backward compatibility, and you empathize with external developers trying to integrate your work
Product and UX sensitivity. You have a good feel for interaction design and visual quality. You notice details like animation timing, gesture ergonomics, and accessibility, and you're willing to iterate with design until the experience feels 'just right.' This lines up strongly with our value of craftsmanship
High-bandwidth collaboration. You communicate clearly with designers, product managers, and other engineers. You can walk through tradeoffs, explain constraints, and adjust plans quickly as we learn from customers
Strong sense of ownership. You're comfortable owning big areas end to end, from rough concept through launch and iteration. You've thrived in fast-moving environments, can operate with limited structure, and care about shipping meaningful improvements quickly without sacrificing quality
Solid understanding of the broader stack. You don't need to be a backend specialist, but you understand how APIs, authentication, data models, and performance characteristics impact the mobile experience. Experience with GraphQL and/or Go is a plus
Preferred
You've built mobile SDKs or framework-style products that other teams integrate into their own applications
You have experience with real-time or media-heavy experiences (messaging, voice, video, or streaming UI)
You've worked on design systems, component libraries, or shared UI kits across platforms, and know how to balance consistency with platform-native conventions
Benefits
Flexible (Unlimited) Paid Time Off
Medical, Dental, and Vision benefits for you and your family
Life Insurance and Disability Benefits
Retirement Plan (e.g., 401K, pension) with Sierra match
Parental Leave
Fertility and family building benefits through Carrot
Lunch, as well as delicious snacks and coffee to keep you energized
Discretionary Benefit Stipend giving people the ability to spend where it matters most
Free alphorn lessons
Company
Sierra
Sierra provides a platform that builds and manages conversational AI agents for customer experiences.
201-500 employees
H1B Sponsorship
Sierra has a track record of offering H1B sponsorships. Please note that this does not
guarantee sponsorship for this specific role. Below presents additional info for your
reference. (Data Powered by US Department of Labor)
Distribution of Different Job Fields Receiving Sponsorship
Represents job field similar to this job
Trends of Total Sponsorships
2025 (11)
2024 (2)
Funding
Current Stage
Growth StageTotal Funding
$635MKey Investors
SoftBank Vision FundGreenoaks
2025-12-04Series Unknown
2025-09-04Series Unknown· $350M
2024-10-28Series Unknown· $175M
Leadership Team
Bret Taylor
Co-Founder
Recent News
2025-12-15
Company data provided by crunchbase