CHICAGO — Facing pressure from an increasingly crowded craft beer market, Lagunitas Brewing Co. announced this week it is laying off 12 percent of its workforce, more than 100 employees companywide.

The California-based brewer posted a letter on its website from CEO Maria Stipp explaining the decision.

The company has about 900 employees across the country, Lagunitas spokeswoman Katie Brown said Thursday.

Employees were notified Tuesday, according to the letter.

Lagunitas is best known for beers like Lagunitas IPA and Lil Sumpin’ Sumpin’ Ale.

The main production facility is in Petaluma, California, and the Chicago plant opened in 2014. Lagunitas sold a 50 percent stake to Heineken International in 2015.

Heineken bought the rest of the company in 2017 for an undisclosed price.

Retail sales of craft beer increased by 8 percent to $26 billion last year, accounting for nearly a quarter of the total U.S. beer market, according to the Brewers Association, a not-for-profit trade association.

There were 6,665 active craft breweries as of June 30, a nearly 20 percent year-over-year increase, according to the association.