FROM THE 80'S TO 2024 - HOW CI TESTS WERE INVENTED AND OPTIMIZED

Summary from the TLDR Web Dev newsletter

Software testing was a manual process in the 1980s, with engineers reviewing code printouts for errors. Automated unit tests became more prevalent in the 1990s, but they were often written and run by specialized testers, leading to slow feedback cycles. The 2000s saw the rise of automated continuous integration (CI) servers like Hudson (Jenkins) that enabled testing of every code change.