Start-up accelerator and Stripe backer more competitive than ever as acceptance rate falls below 1%

In addition to Stripe, the group has worked with global companies including AirBnB and Reddit, and has received 44,000 applications so far this year, its most ever

Garry Tan, chief executive and president of Y Combinator. Photographer: Pedro Fiúza/NurPhoto/Getty Images

The Silicon Valley start-up accelerator which largely supported the development of payments firm Stripe along other Irish businesses has become more competitive than ever in the past year amid a flood of big tech layoffs.

Founded in 2005, Y Combinator is widely considered one of the world's most renowned accelerators, with 6% of its start-ups now worth over $1bn.