auto merge of #17432 : nick29581/rust/contrib, r=brson

[rust.git] / src / doc / complement-lang-faq.md

diff --git a/src/doc/complement-lang-faq.md b/src/doc/complement-lang-faq.md
index ce037251e46b44940fa754d5c8f6185647cfff9d..8db7ba9424fc128beb9c1e4bdcb06f3cdf7bc15e 100644 (file)
--- a/src/doc/complement-lang-faq.md
+++ b/src/doc/complement-lang-faq.md
@@ -1,5 +1,4 @@
-% Language FAQ
-
+% The Rust Language FAQ
 
 ## Are there any big programs written in it yet? I want to read big samples.
 
@@ -29,6 +28,18 @@ You may also be interested in browsing [GitHub's Rust][github-rust] page.
 
 [github-rust]: https://github.com/trending?l=rust
 
+## Is anyone using Rust in production?
+
+Currently, Rust is still pre-1.0, and so we don't recommend that you use Rust
+in production unless you know exactly what you're getting into.
+
+That said, there are two production deployments of Rust that we're aware of:
+
+* [OpenDNS](http://labs.opendns.com/2013/10/04/zeromq-helping-us-block-malicious-domains/)
+* [Skylight](http://skylight.io)
+
+Let the fact that this is an easily countable number be a warning.
+
 ## Does it run on Windows?
 
 Yes. All development happens in lock-step on all 3 target platforms. Using MinGW, not Cygwin. Note that the windows implementation currently has some limitations: in particular 64-bit build is [not fully supported yet][win64], and all executables created by rustc [depend on libgcc DLL at runtime][libgcc].
@@ -72,7 +83,7 @@ We want to maintain the option to parametrize at runtime. We may eventually chan
 
 ## Why aren't values type-parametric? Why only items?
 
-Doing so would make type inference much more complex, and require the implementation strategy of runtime parametrization.
+Doing so would make type inference much more complex, and require the implementation strategy of runtime parameterization.
 
 ## Why are enumerations nominal and closed?
 
@@ -151,4 +162,15 @@ debugging linking in the compiler you might set
 `RUST_LOG=rustc::metadata::creader,rustc::util::filesearch,rustc::back::rpath`
 For a full description see [the logging crate][1].
 
+## How fast is Rust?
+
+As always, this question is difficult to answer. There's still a lot of work to
+do on speed, and depending on what you're benchmarking, Rust has variable
+performance.
+
+That said, it is an explicit goal of Rust to be as fast as C++ for most things.
+Language decisions are made with performance in mind, and we want Rust to be as
+fast as possible. Given that Rust is built on top of LLVM, any performance
+improvements in it also help us be faster.
+
 [1]:log/index.html