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CONTRIBUTING.md

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+# How to Contribute to Wasmer
+
+Thank you for your interest in contributing to Wasmer. This document outlines some recommendations on how to contribute.
+
+## Issues & Feature Requests
+Please use the issue template and provide a failing example if possible to help us recreate the issue.
+
+## Pull Requests
+For large changes, please try reaching the Wasmer using Github Issues or Spectrum Chat to ensure we can accept the change once it is ready.  
+
+We recommend trying the following commands before sending a pull request to ensure code quality:
+- `cargo fmt --all` Ensures all code is correctly formatted.
+- Run `cargo test` in the crates that you are modifying.
+- Run `cargo build --all` (nightly) or `cargo build --all --exclude wasmer-singlepass-backend`
+
+A comprehensive CI test suite will be run by a Wasmer team member after the PR has been created.
+
+### Common Build Issues
+
+**LLVM Dependency**
+
+The LLVM backend requires LLVM to be installed to compile.
+
+So, you may run into the following error:
+```
+Didn't find usable system-wide LLVM.
+No suitable version of LLVM was found system-wide or pointed
+```
+
+**Singlepass Nightly Only**
+
+The singlepass crate depends on nightly so you may need to add the `+nightly` cargo flag to compile this crate.
+`error[E0554]: #![feature] may not be used on the stable release channel`