Engineering (Berlin, Germany)

Engineering

Company Overview

Every 10 minutes, 18 million conversations happen between businesses and consumers around the world. At telli, we are solving the challenges that come with that shift. Today, leading B2C companies like Sky are already using telli to deploy thousands of voice agents to provide their customers with a new experience. telli helps companies build, deploy, and improve consumer-facing AI voice agents at scale. We are a small, AI-pilled team that likes to solve hard problems.

Job Summary

This role is for engineers who care about velocity and solving real customer problems. You won't just ship code; you will own projects end-to-end, make core product and technical decisions, and shape the trajectory of this company. Our philosophy is to push the frontier models to the limits of what is possible.

What You Will Work On

• Voice AI: Ensure voice AI is fast, reliable, and high-quality, including No-infra RAG, racing LLMs, and shadow-testing new transcribers.
• Multi-channel agents: Extend capabilities to handle WhatsApp, email, and continue conversations across channels.
• Call scheduler: Develop a distributed call scheduler to manage load, race conditions, and provider limits across voice orchestration.
• Agent memory: Ensure agents can reason throughout interactions across multiple sessions.
• Charlie: Develop our AI coworker for building, configuring, debugging, and improving agents via app, Slack, Teams, ChatGPT, and Claude.
• Analytics & Dashboard: Replace dashboards with direct answers using Charlie to turn plain-language goals into KPIs.
• Workflows: Enable Charlie to connect agents to CRMs, calendars, and customer systems to perform real work.

Requirements

• You have built and owned distributed systems in production.
• You have strong software fundamentals and learn unfamiliar domains quickly.
• You are eager to act, biased towards action, and want to get your hands dirty.
• You want to figure things out on your own rather than waiting for people to tell you what to do.
• You don’t take what people say as given; you want to understand the problems yourself and challenge the status quo.
• You are excited about agentic coding, but can do it with awareness ensuring quality.
• You are a team player: You optimize for the engineering organization’s output, not your individual output.

Tech Stack

• Voice and backend: Python, uv, FastAPI, LiveKit, TypeScript, Bun, Node.js, Fastify
• Frontend: React, Vite, TanStack
• Data and workflows: PostgreSQL, Redis, Temporal, SQLite
• Observability: OpenTelemetry, Honeycomb, Better Stack
• Infrastructure: AWS, GCP, Azure, Cloudflare, Render, Cerebrium, Modal

Salary & Benefits

• Very competitive pay + equity package
• Access to any (AI) tools
• Large token budget
• Free dinners if you stay late
• Urban sports
• Relocation support if you don’t live in Berlin

What may not make you a good fit

• You prefer a remote-first environment.
• You want to be told exactly what to do.
• You mostly care about the tech, not business outcomes.
• You want to work 9-5.