YC Spring 2026 (P26) founder

Haithem Kchaou

Founder of Callab AI, AI voice agents for on-prem telephony stack.

Callab AIb2boperations5 public signals

Company

Haithem Kchaou is listed as a founder of Callab AI. 58% of the $400B call center industry runs on on-prem phone systems, and until now bringing AI voice automation to them meant ripping out their entire infrastructure first. That's the largest unserved segment in the market. Callab AI connects directly to legacy PBX systems like Avaya, Cisco UCM, and Mitel, and automates up to 70% of call volume with zero migration needed. We plug into these environments without requiring a rip-and-replace. We serve clients across three continents, including brands like Dunkin Donuts.

Founder traction evidence

Public posts and activity attributed directly to this founder.

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    8 weeks in SF and the funniest thing is seeing familiar faces in cafes and not knowing if it's actually them or not. Just realized I’ve been working right next to @dwarkesh_sp in a random cafe

    8 weeks in SF and the funniest thing is seeing familiar faces in cafes and not knowing if it's actually them or not. Just realized I’ve been working right next to @dwarkesh_sp in a random cafe

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    for a startup to succeed, there needs to be speed (which correlates with long working hours) & the right direction. but the right direction >> Speed. The perfect formula is to have both and that's what @UseCorgi 's doing imo

    for a startup to succeed, there needs to be speed (which correlates with long working hours) & the right direction. but the right direction >> Speed. The perfect formula is to have both and that's what @UseCorgi 's doing imo

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    we need a startup positivity movement on x for founders not adding 1M ARR every 2 days. ( just like body positivity on IG) "your sales pipeline doens't define your worth" "every ARR is high and beautiful in its own way." "Arr is just a social construct invented by VCs"...

    we need a startup positivity movement on x for founders not adding 1M ARR every 2 days. ( just like body positivity on IG) "your sales pipeline doens't define your worth" "every ARR is high and beautiful in its own way." "Arr is just a social construct invented by VCs"...

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    Haithem Kchaou (@haithemkchaou) on X

    Those convos set in motion the government's new export controls on foreign national access to Mythos and Fable.