Callab AI

Callab AI builds AI voice agents that plug directly into the legacy, on-premises phone systems most large call centers still run on. Instead of forcing a cloud migration, its carrier-grade telephony stack connects to hardware like Avaya, Cisco UCM, and Mitel over SIP trunks and automates a large share of inbound calls within about a week. Founded by Tunisian engineers Haithem Kchaou and Chehir Dhaouadi and part of Y Combinator's Spring 2026 batch, the company handles calls in Arabic and its dialects plus several other languages, and serves customers across North America, Europe, and the Middle East.