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README.md

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+[![travis][travis-badge]][travis-url]
+[![rustdoc][rustdoc-badge]][rustdoc-url]
+
+[travis-badge]: https://img.shields.io/travis/edef1c/libfringe.svg?style=flat-square
+[travis-url]: https://travis-ci.org/edef1c/libfringe
+[rustdoc-badge]: https://img.shields.io/badge/docs-rustdoc-brightgreen.svg?style=flat-square
+[rustdoc-url]: https://edef1c.github.io/libfringe
+
+# libfringe
+
+  libfringe is a low-level green threading library for Rust.
+  It's usable in freestanding environments (like kernels),
+  but it can also provide an easy-to-use stack allocator using
+  your operating system's memory mapping facility.
+
+## Performance
+
+  libfringe does context switches in 3.5ns flat!
+```
+test swap ... bench:         7 ns/iter (+/- 0)
+```
+
+## Limitations
+
+  libfringe currently doesn't work on anything but x86_64,
+  and is untested on anything but Linux.
+
+## Installation
+
+  libfringe is a [Cargo](https://crates.io) package.
+  It's not stable software yet, so you'll have to use it as a git dependency.
+  Add this to your `Cargo.toml`:
+```toml
+[dependencies.fringe]
+git = "https://github.com/edef1c/libfringe.git"
+```
+
+### Feature flags
+
+  [Cargo's feature flags]: http://doc.crates.io/manifest.html#the-[features]-section
+  libfringe provides several optional features through [Cargo's feature flags].
+  Currently, all of them are enabled by default.
+
+#### `valgrind`
+
+  [Valgrind]: http://valgrind.org
+  [Valgrind] integration. libfringe will register context stacks with Valgrind.
+
+#### `os`
+
+  [Built-in stack allocator]: https://edef1c.github.io/libfringe/fringe/struct.OsStack.html
+  [Built-in stack allocator] using your your operating system's anonymous memory mapping facility.
+  Currently only available for Unix.
+