At telli, we're building the first AI-native phone system.
Since launching last year at Y Combinator (the same investors behind Airbnb, Stripe, Twitch, Coinbase, and others), we've grown >$2M in annualized revenue with a team of only 12 people.
Today, many companies fail in their customer communication not because they don't care, but because they can't keep up. The sheer volume of calls forces to rely on low-quality outsourced call centers or have their internal teams waste hours on repetitive calls.
With telli, our customers now rely on AI voice agents that handle their repetitive calls, freeing human to focus on what matters - talking to customers when it counts. The result: higher efficiency, happier teams, and better customer experiences.
Legacy phone systems weren’t designed for an AI-first world. That is why we are building the first AI-native phone system that lets companies manage both their human and AI teams on one platform.
Our founding team knows this problem inside-out. We ran a 150-person internal call center at Enpal. We know how difficult and expensive it is to scale high-quality customer experience with phone calls.
The opportunity is massive!!! and we're just getting started. We're on a mission to let every company provide a world-class customer experience by ending the era of low-quality call centers.
This is a high-ownership, high-impact role 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 architectural decisions, and shape the future of this company.
We believe in building a small A* engineering team. We plan to keep the core engineering team small, even while we scale and rely on engineers who have super high impact on the growth of the company.
That is why to succeed, you need to be comfortable with working on any part of our stack. One week you might be polishing the UX of our frontend, the next week dive deep into async processing challenges of our voice AI infrastructure. If you only want to work on a specific technology/part of the product, this might not be the right role for you.
what you will do
work closely with our customers, understand their problems, and come up with product experiences that solve their challenges
build scalable backend infrastructure to handle thousands of AI phone calls a day
build intuitive user experiences that make sense in an AI-first world
own high stakes projects end-to-end
tech stack
Our tech stack includes TypeScript, React, TanStack, Node, Python, Postgres as well as Temporal.io, Twilio, and Modal. But more than familiarity with any specific technology, we value a how fast you can learn and the ability to ship end-to-end features.
what makes you a great fityou align with our principles
you love challenging work and consistently go above and beyond
you take full ownership of projects
you want to work in-person in Berlin
you know how to prioritize high-leverage work
you want to work with a smart and driven team with (self-reported) low ego
you want to help build a multi-billion dollar company from the ground up
you prefer a remote-first environment
you like to work on your own with minimum collaboration
you have no prior experience in software engineering teams
you only want to work with specific technologies instead of the entire development stack
you think AI is just "hype" and doesn’t provide real value
you want to work 9-5
above-market pay & equity
access to any (AI) tool that makes you more productive
urban sports subscription
relocation support if you don't live in Berlin
Top Skills
What We Do
AI phone calls that convert









