Facebook

Name	Primary Language	I Use This	Community Rating	12-month Activity & Year-on-Year Change

Name	Primary Language	I Use This	Community Rating	Contributors	Commits
React from Facebook	JavaScript	15	5.0
				Affiliated: —	—
				Outside: 87 -22 (20%)	984 -592 (37%)
HipHop Virtual Machi...	C++	10	5.0
				Affiliated: —	—
				Outside: 808 +127 (18%)	20405 +2751 (15%)
Facebook Presto	Java	4	none
				Affiliated: —	—
				Outside: 189 -1 (0%)	2880 +88 (3%)
react-native	JavaScript	2	none
				Affiliated: —	—
				Outside: 324 -38 (10%)	3440 -1937 (36%)
F Facebook Flow	Rust	2	none
				Affiliated: —	—
				Outside: 44 +4 (10%)	2037 +536 (35%)
F Facebook Infer	N/A	1	none
				Affiliated: —	—
				Outside: —	—
RocksDB	C++	1	none
				Affiliated: —	—
				Outside: — -1 (100%)	— -3 (100%)
Buck	Java	1	none
				Affiliated: —	—
				Outside: —	—
F Facebook CParser	Lua	0	none
				Affiliated: —	—
				Outside: —	—
pyre-check	OCaml	0	none
				Affiliated: —	—
				Outside: 37 -20 (35%)	581 -3561 (85%)
A AsyncDisplayKit	Objective-C	0	none
				Affiliated: —	—
				Outside: —	—