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Thrift is a lightweight remote procedure called framework for scalable cross-language services development that supports C++, PHP, Python, Pearl, Java, Ruby, Erlang, ....
Bigpipe is a kind of custom technology to accelerate page rendering using a pipelining logic. The general idea is to decompose web pages into small chunks called pagelets and pipeline them through several execution stages inside web servers and browsers, so eventually it helps increasing performance and speed.
Reference
http://blog-bhaskaruni.blogspot.com/2012/12/facebook-architecture.html