Both are quite similar at a high level. They provide generic utilities for improving synchronization, strings, random number generators, high performance containers, etc. Both are no stable ABI guaranteed, live at head encouraged.

At a more detailed level, I find Folly much more substantial than Abseil. For example, both provide high performance hash tables. Abseil also provides a BTree-based map, which Folly does not. But Folly provides concurrent skip lists, LRU evicted hash maps, a high performance MPMC queue, etc. And that's just talking about data structures. Folly also has asynchronous I/O tools, futures, reference-counted buffers for IO, and many other things outside the scope of Abseil.

Personally, I am loving the asynchronous I/O mechanisms in Folly. It feels more expressive and results in cleaner code than boost ASIO. Just a first impression though, I am relatively new to the library.

Folly has Boost as a dependency and do not repeat features that already present in there. Not a problem if your project already uses Boost. Abseil seems to be self-sufficient.

Even i wonder about this! Also is Abseil widely used in the industry or only at Google?

Abseil is used extensively in Envoy Proxy. The project is a top level Cloud Native Computing Foundation (CNCF) project however Google are one of the top contributors.

I doubt it. Google lives at head and breaks things. Industry likes stability in general I have code from 1996 that I still need to support on cpus that were current back then. Nobody has written a new compiler for those cpus so I am stuck with whatever the old compiler supports.

OT: wiineeth, your account is shadow banned. I looked through your history and can't really tell why, but you should email hn and ask them to lift the ban, since IMO you don't look like a bad member in a community.

We just started using it for its flat_hash_map.