Plex Coffee slashed onboarding from weeks to days using custom GPTs

Ask any founder what breaks when you scale, and they’ll tell you the same thing: culture. For Plex Coffee, a lean, tech-inspired café chain in Singapore, growth from one location to four started to erode the two things that made it special—personal customer engagement and consistent training. Co-founders Philipp Cheng and Max Kamp, who used to personally train every barista, suddenly found their store managers drowning in a flood of repetitive WhatsApp questions. “We were struggling increasingly with knowledge sharing,” Cheng says, noting that routine queries were pulling managers away from the community events they value most.

The real trouble was that a 25-page handbook, which should have been the single source of truth, was being completely ignored. Centralizing that knowledge in Notion was the obvious next step, but their keyword search hit a wall because staff used different language to describe the same things. The breakthrough came by connecting Notion to ChatGPT Business, letting employees ask questions in natural language from an in-store iPad. That single change cut operational WhatsApp messages by over 50%.

Cheng then weaponized the dusty handbook by uploading it into a custom GPT that now anchors the entire onboarding process. The GPT is prompted to teach core values and technical details conversationally instead of just dumping information. The result is exactly the kind of metric founders dream of: onboarding time compressed from weeks to days, with store managers reclaiming the bandwidth to focus on guest experience rather than coaching basics.

With the people-problems solved, Plex is now applying the same logic elsewhere. Cheng uses ChatGPT’s deep research tools to model revenue potential for new locations, explaining odd demand shifts by surfacing local events or student migration patterns. They’re even experimenting with having Agent place orders directly with suppliers to kill repetitive admin work. As Plex plans to hit ten cafés while keeping operations lean, Cheng’s bet is that AI doesn’t just cut costs—it creates the space for the human hospitality that made the brand work in the first place.