Backend Engineer

Backend EngineerAI is changing how the world communicates — and LILT is leading that transformation. We're on a mission to make the world's information accessible to everyone, regardless of the language they speak. We use cutting-edge AI, machine translation, and human-in-the-loop expertise to translate content faster, more accurately, and more cost-effectively without compromising on brand, voice, or quality.At LILT, we empower our teammates with leading tools, global collaboration, and growth opportunities to do their best work. Our company virtues—Work Together, Win Together; Find a Way or Make One; Dance in the Customer's Shoes; Quicker Than They Expect; Quality is Job 1—guide everything we do. We are trusted by Intel Corporation, Canva, the United States Department of Defense, the United States Air Force, ASICS, and hundreds of global Enterprises. Backed by Sequoia, Intel Capital, and Redpoint, we're building a category-defining company in a $50B+ global translation market being redefined by AI.Lilt's Converse product delivers real-time, multi-party translation for high-stakes conversations — from offline, device-based deployments in the field to live meetings on enterprise collaboration platforms. We're expanding Converse to support any number of participants, speaking any combination of languages, joining from a growing set of form factors — with live translation delivered N-way, directly on the meeting stage, and cleared interpreters reviewing only the segments that need a human eye. You will build and operate the backend services that make this work: per-participant audio ingestion, real-time diarization and translation orchestration, and the routing logic that gets a flagged segment in front of the right interpreter and broadcasts their correction back out in real time. This is a ground-floor opportunity to help build a brand-new product surface, on a team whose existing products serve some of the world's largest global brands.As a Backend Engineer on the Create team, you'll work closely with senior engineers and Product to build the services powering this Converse expansion — the real-time translation pipeline and the meeting-platform integration — taking well-scoped services and features from design through production with support and code review from more senior teammates. You'll help define clean API contracts with the frontend/interpreter-workbench engineers, contribute to the event-driven correction and broadcast system, and grow into owning larger pieces of the backend architecture as the product and team scale.Location & eligibility: This position requires US citizenship and residence in the United States. Preferred locations are Washington, D.C.; Boston, MA; and Indianapolis, IN.What You'll DoBuild and maintain backend services for the real-time translation pipeline: audio ingestion, diarization hookups, streaming ASR/MT orchestration, and result fan-out to every configured meeting languageImplement the event-driven routing logic that flags low-confidence segments and routes them to the correct on-call interpreter by languageBuild APIs and services backing the bot/agent participant and meeting side panel that deliver translation into the host meeting platform, with guidance from senior engineersContribute to the interpreter correction and broadcast system — ensuring corrections are isolated to the correct language and broadcast to all participants in real timeWrite and maintain automated tests (unit, integration, e2e) and contribute to CI/CD pipelines (GitHub Actions) for new backend servicesInstrument services for observability — logging, metrics, tracing — to support debugging of latency-sensitive, multi-party sessionsPartner with frontend/fullstack engineers on the Create team to define clean API contracts between backend services and the live meeting UI and interpreter workbenchParticipate in on-call rotation and help triage production issues as the product moves toward GAHelp generate post-meeting assets: diarized transcripts, exportable formats (TXT/WebVTT/JSON), and per-line verification metadataWhat We're Looking ForRequired2–5 years of professional backend software engineering experience, ideally including production systems that handle real-time or streaming dataExperience building REST API endpoints as well as streaming services with WebSockets, gRPC, message queues, or comparable low-latency/event-driven patternsSolid experience with Node.js/TypeScript, Java, Python, or a comparable backend language/ecosystem, and the ability to work across more than one when neededExperience building and consuming REST/GraphQL APIs, including authentication patterns (OAuth, API keys/tokens, service accounts)Comfort with relational/NoSQL data modeling for session state, transcripts, and configuration dataSolid grasp of testing and delivery practices: CI/CD and automated integration/e2e testsAbility to take a well-scoped ticket or spec and ship it with minimal oversight, while communicating blockers and timeline risk earlyUS citizenship and residence in the United StatesStrong PlusExperience with speech/audio pipelines: diarization, streaming ASR, or audio stream handlingExperience integrating with third-party platform APIs, SDKs, or webhooks (Slack, Zoom, or similar collaboration platforms)Familiarity with localization/TMS workflows: XLIFF, Translation Memory, MT vs. human translation pipelinesExperience with event-driven/pub-sub architectures (Kafka, Pub/Sub, or similar)Enough frontend/React exposure to reason about API contracts with a real-time, stateful UIBonusHands-on Microsoft Teams app or bot development specifically (Teams Toolkit, Bot Framework, Azure Communication Services, Microsoft Graph)Experience working on 0-to-1 products within a larger, established companyInterest or coursework in NLP/ML systemsExperience with observability tooling (e.g., Datadog) in production, latency-sensitive systems Lilt