Open Source Summit Europe 2024

Application Binary Interface (ABI), in contrast to the more often heard Application Programming Interface (API), is not as widely discussed, but is every bit as important as the latter. It is what allows us to run programs that are compiled 10 years ago on the latest system, and still expect it to work. In this talk, we will introduce the audience to the concept of ABI, explain its difference from API, and and lay out what exactly breaks ABI, as well as cover the symptoms of such breakage. Further more, we will detail how ABI breakage can be detected or prevented, and discuss some specific cases: Linux Kernel's ABI, Python's stable ABI, and Foreign Function Interface.