job summary
You will own the architecture and design of the platform behind Slack's voice agent - a native mobile voice/AI assistant experience inside the Slack mobile ecosystem. This is production work, not prototyping: your services, APIs, and pipelines must meet the bar of Slack's production codebase - modular, tested, linted, accessible, and performant at Slack's scale (tens of millions of users).
Slack is an extremely design-driven organization. Every hire, engineering included, must have demonstrable design sensibility and experience working within (or adjacent to) a mature design system. As the principal engineer on the project, you set the technical standard that our iOS and Android client engineers build against.
location: Telecommute
job type: Contract
salary: $178.29 - 188.29 per hour
work hours: 8am to 5pm
education: Bachelors
responsibilities
- 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.
qualifications
**Must-have
10+ years of software engineering experience, operating at principal/architect level on large-scale distributed systems - a demonstrated track record of architecture and design ownership, not just implementation.
Expert-level 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.
Shipped and maintained systems at 100K+ MAU minimum; 1M+ MAU strongly preferred - with the observability, incident discipline, and phased-release experience that scale demands.
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.
**Nice-to-have
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, , 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).
skills
Alexa,Maven,iOS,APIs,API,audio streaming,code review,streaming,large-scale distributed systems,Figma,Git,Java,JVM,Jenkins,Kotlin,LLM,versioning,Notion,Vercel,pagination,real-time systems,REST API design,SOAP services,SOAP,Siri,software engineering,Stripe,AI assistant,web services,WSDL,WebRTC,WebSockets,empathy,architecture,client-side,prototyping,dependency management,design system,design language,governance,infrastructure,Rigorous testing,security,technical standard