[ableal]

I saw this one pass by a few weeks ago, it may interest you:

http://yieldprolog.sourceforge.net/

"Yield Prolog lets you embed Prolog programs directly in Python, C# [1] or Javascript [2] by using the yield keyword."

[silentbicycle]

If it's implemented in C with a simple API, it should be easy to use from anything that has a C FFI. I'd rather not make it too language-specific - there's a huge duplication of effort as new languages appear.

Lua and SQLite are both great examples of libraries whose APIs make them straightforward to embed in other languages.