Whatever you might think of Torvalds personally, this (Wikipedia) is downright impressive.
The development of Git began on 3 April 2005. The project was announced on 6 April, and became self-hosting as of 7 April. The first merge of multiple branches was done on 18 April. Torvalds achieved his performance goals; on 29 April, the nascent Git was benchmarked recording patches to the Linux kernel tree at the rate of 6.7 per second.
Writing a version control system that can host its own source in 4 days is amazing. BTW, April 3, 2005 was Sunday 🙂
It also turned out that “git” means “the two of you” in Old English.