On Cyber Monday, The GitHub Shop offers a 25% discount on all orders using the coupon code CYBERCAT, with the sale ending Tuesday at midnight PST. The promotion also includes the restocking of GitHub Mugs and the introduction of a new Blacktocat t-shirt, described as a soft, black-on-black American Apparel Tri-blend that is ideal for gifting. This special offer is available for international shipping, encouraging customers to explore the merchandise available in the shop.