Mobile Software Engineer

You will own the architecture and design of the platform behind a voice agent - a native mobile voice/AI assistant experience inside the mobile ecosystem. This is production work, not prototyping: your services, APIs, and pipelines must meet the bar of the application’s production codebase - modular, tested, linted, accessible, and performant at scale (tens of millions of users). As the principal engineer on the project, you set the technical standard that our iOS and Android client engineers build against., * Own end-to-end architecture and technical design for the voice agent platform: service decomposition, API contracts, data models, failure modes, and latency/capacity budgets for real-time conversational experiences.

• Design, build, and operate the RESTful web services that power the voice agent - voice capture/playback backends, streaming agent responses, session state, and deep integration with Slack’s mobile apps - and integrate with (and help modernize) existing SOAP-based enterprise web services in the CIO organization.
• Architect real-time communication layers (WebSockets / streaming APIs) for low-latency voice and agent responses: connection management, backpressure, reconnection, and graceful degradation.
• Define the client-service contracts that iOS and Android engineers implement against; review client integration code for architectural soundness.
• Own CI/CD and build infrastructure: Jenkins pipelines (declarative pipelines, shared libraries), Maven builds and artifact management, quality gates, feature flags, and staged rollouts.
• Lead design reviews and code reviews to Slack’s standards; author architecture decision records; mentor senior engineers on the team.
• Collaborate daily with design and product - ensuring voice interaction states (listening / thinking / speaking / error / interruption) are technically realized to spec, not approximately.

• Looking to move fast, we need people right now, can begin interviewing as soon as we see a good candidate.
• Will be Fully remote. Should be willing to work PT hours
• Where are you at in design and what pain points do you need them to jump into? We have a model, we train models. Most of the team are researchers and engineers, not developers. Seeking a strong developer to join the team.
• Will be writing production grade code. Need someone who can plug into the production code base of one of our products and come up with a design that integrates our model into their mobile app (iOS or Android).
• Voice application is nice to have, not a must have, as long as they can design app that is beautiful and works well. Language learning app would be nice to see. Voice AI apps are not well represented in the industry. Language learning app would be a good fit. This being a voice app, Websocket connections would be relevant. Real time translation is relevant.
• Java or Kotlin, will be ok do not need both skills
• Should have experience directly using websocket or real time streaming to user., * 4-10 years of software engineering experience.
• Strong REST API design (versioning, pagination, error models, idempotency, authN/authZ) and working fluency with SOAP/WSDL enterprise web services, including migrating or wrapping SOAP services behind modern REST interfaces.
• Production experience with real-time systems: WebSockets, streaming APIs, low-latency backends; voice/audio streaming experience is a strong plus.
• Deep JVM services background (Java and/or Kotlin) with expert-level Maven (multi-module builds, dependency management, plugin configuration) and Jenkins (pipeline-as-code, shared libraries, scaling build infrastructure).
• Experience building and operating services consumed by mobile clients - you understand what iOS/Android teams need from an API contract.
• Rigorous testing culture: unit, integration, and contract testing embedded in CI; Git-based code review culture.
• Design sensibility: experience working within or adjacent to a mature design system at a design-driven company., * Prior work at a company with a strong, recognized design language - e.g., Apple, Airbnb, Duolingo, Linear, Figma, Notion, Stripe, Cash App/Block, Headspace, Robinhood, Vercel.
• Voice/conversational AI product experience (e.g., OpenAI, Character.ai, Replika, Siri/Alexa teams): ASR/TTS integration, LLM streaming backends, token-streaming architectures, WebRTC.
• Hands-on familiarity with Swift/iOS or Kotlin/Android - enough to review client-side integration with empathy and precision.
• Experience in enterprise/CIO-organization environments: security, compliance, and governance requirements for internal-facing platforms.
• Accessibility at production depth (voice experiences must be accessible by default).