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 Contributing to Paper
 ==========================
-PaperMC has a very lenient policy towards PRs, but would prefer that you try and adhere to the following guidelines.
+PaperMC is happy you're willing to contribute to our projects. We are usually
+very lentient with all submitted PRs, but there are still some guidelines you
+can follow to make the approval process go more smoothly.
+
+**Table of contents:**
+<!-- Please don't remove the following comments.
+To generate and update the TOC: https://github.com/mzlogin/vim-markdown-toc -->
+<!-- vim-markdown-toc GFM -->
+
+* [Use a Personal Fork and not Organization](#use-a-personal-fork-and-not-organization)
+* [Requirements](#requirements)
+* [Understanding Patches](#understanding-patches)
+* [Adding Patches](#adding-patches)
+* [Modifying Patches](#modifying-patches)
+  * [Method 1](#method-1)
+    * [Using the Paper tool](#using-the-paper-tool)
+    * [Manual method: Stashing](#manual-method-stashing)
+  * [Method 2 - Fixup commits](#method-2---fixup-commits)
+    * [Manual method](#manual-method)
+    * [Automatic method](#automatic-method)
+* [PR Policy](#pr-policy)
+* [Formatting](#formatting)
+* [Patch Notes](#patch-notes)
+* [Obfuscation Helpers](#obfuscation-helpers)
+* [Configuration files](#configuration-files)
+  * [PaperConfig example](#paperconfig-example)
+  * [PaperWorldConfig example](#paperworldconfig-example)
+* [Frequently Asked Questions](#frequently-asked-questions)
+  * [I can't find the NMS file I need!](#i-cant-find-the-nms-file-i-need)
+  * [Where can I learn how to name method/field?](#where-can-i-learn-how-to-name-methodfield)
+  * [My commit doesn't need a build, what do I do?](#my-commit-doesnt-need-a-build-what-do-i-do)
+  * [Patching and building is *really* slow, what can I do?](#patching-and-building-is-really-slow-what-can-i-do)
+  * [I wrote some API, how do I use it in Paper-Server?](#i-wrote-some-api-how-do-i-use-it-in-paper-server)
+
+<!-- vim-markdown-toc -->
 
 ## Use a Personal Fork and not Organization
-Paper will routinely modify your PR for you to rebase it on latest or take care of any minor nitpicks that we can
-just solve for you instead of making you go back for a trivial item.
 
-However, if you use an Organization for the PR, this prevents Paper from doing this, and will require us to manually
-merge it and close the PR instead of it being marked as the purple merged.
+Paper will routinely modify your PR, whether it's a quick rebase or to take care
+of any minor nitpicks we might have. Often, it's better for us to solve these
+problems for you than make you go back and forth trying to fix it yourself.
 
-We much prefer to have merged PR's show as merged, so please do not use organizations repo's for PR as GitHub sadly
-does not support maintainers pushing to them.
+Unfortunately, if you use an organization for your PR, it prevents Paper from
+modifying it. This requires us to manually merge your PR, resulting in us
+closing the PR instead of marking it as merged.
 
-See [https://github.com/isaacs/github/issues/1681](https://github.com/isaacs/github/issues/1681)
+We much prefer to have PRs show as merged, so please do not use repositories
+on organizations for PRs.
 
-## Understanding Patches
-Patches to Paper are very simple, but center around the directories 'Paper-API' and 'Paper-Server'
+See <https://github.com/isaacs/github/issues/1681> for more information on the
+issue.
 
-Assuming you already have forked the repository:
+## Requirements
 
-1. Pull the latest changes from the main repository
-1. Type `./paper patch` in git bash to apply the changes from upstream
-1. cd into `Paper-Server` for server changes, and `Paper-API` for API changes
+To get started with PRing changes, you'll need the following software, most of
+which can be obtained in (most) package managers such as `apt` (Debian / Ubuntu;
+you will most likely use this for WSL), `homebrew` (macOS / Linux), and more:
 
-These directories aren't git repositories in the traditional sense:
+- `git` (package `git` everywhere);
+- `patch` (often package `patch`);
+- A Java 8 or later JDK (packages vary, use Google/DuckDuckGo/etc.).  
+If you need one, you can find them on [AdoptOpenJDK](https://adoptopenjdk.net/).
+- `maven` (often package `maven`; can be found on
+[Apache's site](https://maven.apache.org/download.cgi) too).
 
-- Every single commit in Paper-Server/API is a patch. 
-- 'origin/master' points to a directory similar to Paper-Server/API but for Paper
-- Typing `git status` should show that we are 10 or 11 commits ahead of master, meaning we have 10 or 11 patches that Paper and Spigot don't
-  - If it says something like `212 commits ahead, 207 commits behind`, then type `git fetch` to update spigot/paper
+If you're on Windows, check
+[the section on WSL](#patching-and-building-is-really-slow-what-can-i-do).
 
-## Adding Patches
-Adding patches to Paper is very simple:
+If you're compiling with Docker, you can use the
+[`adoptopenjdk`](https://hub.docker.com/_/adoptopenjdk/) images like so:
 
-1. Modify `Paper-Server` and/or `Paper-API` with the appropriate changes
-1. Type `git add .` to add your changes
-1. Run `git commit` with the desired patch message
-1. Run `./paper rebuild` in the main directory to convert your commit into a new patch
-1. PR your patches back to this repository
+```console
+# docker run -it -v "$(pwd)":/data --rm adoptopenjdk:8-jdk-hotspot bash
+Pulling image...
 
-Your commit will be converted into a patch that you can then PR into Paper
+root@abcdefg1234:/# javac -version
+javac 1.8.0_252
+```
 
-## Help! I can't find the file I'm looking for!
-By default, Paper (and upstream) only import files that we make changes to.
-If you would like to make changes to a file that isn't present in Paper-Server's source directory, you
-just need to add it to our import script to be ran during the patch process.
+## Understanding Patches
 
-1. Save (rebuild) any patches you are in the middle of working on!
-1. Identify the names of the files you want to import.
-   - A complete list of all possible file names can be found at ```./work/Minecraft/$MCVER/spigot/net/minecraft/server```
-1. Open the file at `./scripts/importmcdev.sh` and add the name of your file to the script.
-1. Re-patch the server `./paper patch`
-1. Edit away!
+Paper is mostly patches and extensions to Spigot. These patches/extensions are
+split into different directories which target certain parts of the code. These
+directories are:
+
+- `Paper-API` - Modifications to `Spigot-API`/`Bukkit`;
+- `Paper-MojangAPI` - An API for
+[Mojang's Brigadier](https://github.com/Mojang/brigadier);
+- `Paper-Server` - Modifications to `Spigot`/`CraftBukkit`.
+
+Because the entire structure is based on patches and git, a basic understanding
+of how to use git is required. A basic tutorial can be found here:
+<https://git-scm.com/docs/gittutorial>.
+
+Assuming you have already forked the repository:
+
+1. Clone your fork to your local machine;
+1. Type `./paper patch` in a terminal to apply the changes from upstream;
+1. cd into `Paper-Server` for server changes, and `Paper-API` for API changes.  
+You can also run `./paper server` or `./paper api` for these same directories
+respectively.
+1. You can also run `./paper setup`, which allows you to type `paper <command>`
+from anywhere in the Paper structure in most cases.
+
+`Paper-Server` and `Paper-API` aren't git repositories in the traditional sense:
+
+- Every single commit in `Paper-Server`/`Paper-API` is a patch;
+- `origin/master` points to a directory similar to `Paper-Server`/`Paper-API`
+but for Paper;
+- Typing `git status` should show that we are 10 or 11 commits ahead of master,
+meaning we have 10 or 11 patches Spigot and CraftBukkit don't.
+   - If it says something like `212 commits ahead, 207 commits behind`,
+   cd into the root directory of the cloned repository and type `git fetch` to
+   update your upstream. Setting up a remote for the upstream Paper repository
+   might be necessary.
+
+## Adding Patches
 
-This change is temporary! DO NOT COMMIT CHANGES TO THIS FILE!
-Once you have made your changes to the new file, and rebuilt patches, you may undo your changes to importmcdev.sh
+Adding patches to Paper is very simple:
 
-Any file modified in a patch file gets automatically imported, so you only need this temporarily
-to import it to create the first patch.
+1. Modify `Paper-Server` and/or `Paper-API` with the appropriate changes;
+1. Type `git add .` inside these directories to add your changes;
+1. Run `git commit` with the desired patch message;
+1. Run `./paper rebuild` in the main directory to convert your commit into a new
+patch;
+1. PR the generated patch file(s) back to this repository.
 
-To undo your changes to the file, type `git checkout scripts/importmcdev.sh`
+Your commit will be converted into a patch that you can then PR into Paper.
 
+> ❗ Please note that if you have some specific implementation detail you'd like
+> to document, you should do so in the patch message *or* in comments.
 
 ## Modifying Patches
+
 Modifying previous patches is a bit more complex:
 
 ### Method 1
-This method works by temporarily resetting HEAD to the desired commit to edit using rebase.
 
-However, while in the middle of an edit, unless you also reset your API to a related commit, you will not be able to compile.
+This method works by temporarily resetting your `HEAD` to the desired commit to
+edit it using `git rebase`.
+
+> ❗ While in the middle of an edit, you will not be able to compile unless you
+> *also* reset the opposing module(s) to a related commit. In the API's case,
+> you must reset the Server, and reset the API if you're editing the Server.
 
 #### Using the Paper tool
-The PaperMC build tool provides a handy command to automatically do this type of patch modification.
-
-1. Type `./paper edit server` or `./paper edit api` depending on which project you want to edit.
-   - It should show something like [this](https://gist.github.com/zachbr/21e92993cb99f62ffd7905d7b02f3159).
-1. Replace `pick` with `edit` for the commit/patch you want to modify, and "save" the changes
-   - Only do this for one commit at a time.
-1. Make the changes you want to make to the patch.
-1. Type `./paper edit continue` to finish and rebuild patches.
-1. PR your modifications back to this project.
-
-#### Manual method - Stashing
-In case you need something more complex or want more control, this step-by-step instruction does
-exactly what the above slightly automated system does.
-
-1. If you have changes you are working on type `git stash` to store them for later.
-   - Later you can type `git stash pop` to get them back.
-1. Type `git rebase -i upstream/upstream`
-   - It should show something like [this](https://gist.github.com/zachbr/21e92993cb99f62ffd7905d7b02f3159).
-1. Replace `pick` with `edit` for the commit/patch you want to modify, and "save" the changes.
-   - Only do this for one commit at a time.
-1. Make the changes you want to make to the patch.
-1. Type `git add .` to add your changes.
-1. Type `git commit --amend` to commit.
-   - **MAKE SURE TO ADD `--amend`** or else a new patch will be created.
-   - You can also modify the commit message here.
-1. Type `git rebase --continue` to finish rebasing.
-1. Type `./paper rebuild` in the main directory.
+
+The PaperMC build tool provides a handy command to automatically do this type of
+patch modification.
+
+1. Type `./paper edit server` or `./paper edit api` depending on which project
+you want to edit;
+   - It should show something like
+   [this](https://gist.github.com/zachbr/21e92993cb99f62ffd7905d7b02f3159) in
+   the text editor you get.
+   - If your editor does not have a "menu" at the bottom, you're using `vim`.  
+   If you don't know how to use `vim` and don't want to
+   learn, enter `:q!` and press enter. Before redoing this step, do
+   `export EDITOR=nano` for an easier editor to use.
+1. Replace `pick` with `edit` for the commit/patch you want to modify, and
+"save" the changes;
+   - Only do this for **one** commit at a time.
+1. Make the changes you want to make to the patch;
+1. Type `./paper edit continue` in the root directory to finish and rebuild
+patches;
+1. PR your modified patch file(s) back to this repository.
+
+#### Manual method: Stashing
+
+In case you need something more complex or want more control, these step-by-step
+instruction do exactly what the above slightly automated system above does.
+
+1. If you have changes you are working on, type `git stash` to store them for
+later;
+   - You can type `git stash pop` to get them back at any point.
+1. Type `git rebase -i upstream/upstream`;
+   - It should show something like
+   [this](https://gist.github.com/zachbr/21e92993cb99f62ffd7905d7b02f3159) in
+   the text editor you get.
+   - If your editor does not have a "menu" at the bottom, you're using `vim`.  
+   If you don't know how to use `vim` and don't want to
+   learn, enter `:q!` and press enter. Before redoing this step, do
+   `export EDITOR=nano` for an easier editor to use.
+1. Replace `pick` with `edit` for the commit/patch you want to modify, and
+"save" the changes;
+   - Only do this for **one** commit at a time.
+1. Make the changes you want to make to the patch;
+1. Type `git add .` to add your changes;
+1. Type `git commit --amend` to commit;
+   - **Make sure to add `--amend`** or else a new patch will be created.
+   - You can also modify the commit message and author here.
+1. Type `git rebase --continue` to finish rebasing;
+1. Type `./paper rebuild` in the root directory;
    - This will modify the appropriate patches based on your commits.
-1. PR your modifications back to this project.
+1. PR your modified patch file(s) back to this repository.
 
-### Method 2 (sometimes easier) - Manually moving commits
-If you are simply editing a more recent commit or your change is small, simply making the change at HEAD and then moving the commit after you have tested it may be easier.
+### Method 2 - Fixup commits
 
-This method has the benefit of being able to compile to test your change without messing with your API HEAD.
+If you are simply editing a more recent commit or your change is small, simply
+making the change at HEAD and then moving the commit after you have tested it
+may be easier.
 
-1. Make your change while at HEAD
-1. Make a temporary commit. You don't need to make a message for this.
-1. Type `git rebase -i upstream/upstream`, move (cut) your temporary commit and move it under the line of the patch you wish to modify.
-1. Change the `pick` with `f` (fixup) or `s` (squash) if you need to edit the commit message 
-1. Type `./paper rebuild` in the main directory
-   - This will modify the appropriate patches based on your commits
-1. PR your modifications to github
+This method has the benefit of being able to compile to test your change without
+messing with your HEADs.
 
-### Method 3 - Fixup Commits
-This is the automated way of doing Method 2. Basically, you make your changes at HEAD, but use fixup commits to modify earlier patches and git will rebase the commits to the right place and squash them.
+#### Manual method
 
-1. Make your change while at HEAD
-1. Make a fixup commit. `git commit -a --fixup <hashOfPatchToFix>`. You can get the hash by looking at `git log` or `git blame`, your IDE can assist you too.  
-Alternatively, if you only know the name of the patch, you can do `git commit -a --fixup "Subject of Patch name"`
-1. Rebase with autosquash: `git rebase --autosquash -i upstream/upstream`. It will move your fixup commit to the right place.
-1. Type `./paper rebuild` in the main directory
-   - This will modify the appropriate patches based on your commits
-1. PR your modifications to github
+1. Make your change while at HEAD;
+1. Make a temporary commit. You don't need to make a message for this;
+1. Type `git rebase -i upstream/upstream`, move (cut) your temporary commit and
+move it under the line of the patch you wish to modify;
+1. Change the `pick` to the appropriate action:
+   1. `f`/`fixup`: Merge your changes into the patch without touching the
+  message.
+   1. `s`/`squash`: Merge your changes into the patch and use your commit message
+  and subject.
+1. Type `./paper rebuild` in the root directory;
+   - This will modify the appropriate patches based on your commits.
+1. PR your modified patch file(s) back to this repository.
+
+#### Automatic method
+
+1. Make your change while at HEAD;
+1. Make a fixup commit. `git commit -a --fixup <hashOfPatchToFix>`;
+   - You can also use `--squash` instead of `--fixup` if you want the commit
+   message to also be changed.
+   - You can get the hash by looking at `git log` or `git blame`; your IDE can
+  assist you too.
+   - Alternatively, if you only know the name of the patch, you can do
+  `git commit -a --fixup "Subject of Patch name"`.
+1. Rebase with autosquash: `git rebase --autosquash -i upstream/upstream`.
+This will automatically move your fixup commit to the right place, and you just
+need to "save" the changes.
+1. Type `./paper rebuild` in the root directory;
+   - This will modify the appropriate patches based on your commits.
+1. PR your modified patch file(s) back to this repository.
 
 ## PR Policy
-We'll accept changes that make sense. You should be able to justify their existence, along with any maintenance costs that come with them. Remember, these changes will affect everyone who runs Paper, not just you and your server.
-While we will fix minor formatting issues, you should stick to the guide below when making and submitting changes.
+
+We'll accept changes that make sense. You should be able to justify their
+existence, along with any maintenance costs that come with them. Using
+[obfuscation helpers](#obfuscation-helpers) aids in the maintenance costs.
+Remember that these changes will affect everyone who runs Paper, not just you
+and your server.
+
+While we will fix minor formatting issues, you should stick to the guide below
+when making and submitting changes.
 
 ## Formatting
-All modifications to non-Paper files should be marked
-- Multi line changes start with `// Paper start` and end with `// Paper end`
-- You can put a messages with a change if it isn't obvious, like this: `// Paper start - reason`
-  - Should generally be about the reason the change was made, what it was before, or what the change is
-  - Multi-line messages should start with `// Paper start` and use `/* Multi line message here */` for the message itself
-- Single line changes should have `// Paper` or `// Paper - reason`
-- For example:
-````java
+
+All modifications to non-Paper files should be marked.
+
+- Multi-line changes start with `// Paper start` and end with `// Paper end`;
+- You can put a comment with an explanation if it isn't obvious, like this:
+`// Paper start - reason`.
+   - The comments should generally be about the reason the change was made, what
+  it was before, or what the change is.
+   - Multi-line messages should start with `// Paper start` and use `/* Multi
+  line message here */` for the message itself.
+- One-line changes should have `// Paper` or `// Paper - reason`.
+
+Here's an example of how to mark changes by Paper:
+
+```java
 entity.getWorld().dontbeStupid(); // Paper - was beStupid() which is bad
 entity.getFriends().forEach(Entity::explode);
 entity.a();
@@ -147,24 +273,40 @@ entity.b();
 Location spawnLocation = ((CraftWorld)entity.getWorld()).getSpawnLocation();
 entity.getWorld().explode(new BlockPosition(spawnLocation.getX(), spawnLocation.getY(), spawnLocation.getZ()));
 // Paper end
-````
-- We generally follow usual java style, or what is programmed into most IDEs and formatters by default
-  - This is also known as oracle style
-  - It is fine to go over 80 lines as long as it doesn't hurt readability
-  - There are exceptions, especially in Spigot-related files
-  - When in doubt, use the same style as the surrounding code
-  
+```
+
+We generally follow usual Java style (aka. Oracle style), or what is programmed
+into most IDEs and formatters by default. There are a few notes, however:
+- It is fine to go over 80 lines as long as it doesn't hurt readability.  
+There are exceptions, especially in Spigot-related files
+- When in doubt or the code around your change is in a clearly different style,
+use the same style as the surrounding code.
+
 ## Patch Notes
-When submitting patches to Paper, we may ask you to add notes to the patch header.
-While we do not require it for all changes, you should add patch notes when the changes you're making are technical or complex.
-It is very likely that your patch will remain long after we've all forgotten about the details of your PR, patch notes will help
-us maintain it without having to dig back through GitHub history looking for your PR.
 
-These notes should express the intent of your patch, as well as any pertinent technical details we should keep in mind long-term.
-Ultimately, they exist to make it easier for us to maintain the patch across major version changes.
+When submitting patches to Paper, we may ask you to add notes to the patch
+header. While we do not require it for all changes, you should add patch notes
+when the changes you're making are technical, complex, or require an explanation
+of some kind. It is very likely that your patch will remain long after we've all
+forgotten about the details of your PR; patch notes will help us maintain it
+without having to dig back through GitHub history looking for your PR.
+
+These notes should express the intent of your patch, as well as any pertinent
+technical details we should keep in mind long-term. Ultimately, they exist to
+make it easier for us to maintain the patch across major version changes.
 
-If you add a long message to your commit in the Paper-Server/API repos, the rebuildPatches command will handle these patch
-notes automatically as part of generating the patch file. Otherwise if you're careful they can be added by hand (though you should be careful when doing this, and run it through a patch and rebuild cycle once or twice).
+If you add a message to your commit in the `Paper-Server`/`Paper-API`
+directories, the rebuild patches script will handle these patch notes
+automatically as part of generating the patch file. If you are not
+extremely careful, you should always just `squash` or `amend` a patch (see the
+above sections on modifying patches) and rebuild.
+
+Editing messages and patches by hand is possible, but you should patch and
+rebuild afterwards to make sure you did it correctly. This is slower than just
+modifying the patches properly after a few times, so you will not really gain
+anything but headaches from doing it by hand.
+
+Underneath is an example patch header/note:
 
 ```patch
 From 02abc033533f70ef3165a97bfda3f5c2fa58633a Mon Sep 17 00:00:00 2001
@@ -192,13 +334,22 @@ index a92bf8967..d0ab87d0f 100644
 ```
 
 ## Obfuscation Helpers
-In an effort to make future updates easier on ourselves, Paper tries to use obfuscation helpers whenever possible. The purpose of these helpers is to make the code more readable. These helpers should be be made as easy to inline as possible by the JVM whenever possible.
 
-An obfuscation helper to get an obfuscated field may be as simple as something like this:
+In an effort to make future updates easier on ourselves, Paper tries to use
+obfuscation helpers whenever possible. The purpose of these helpers is to make
+the code more readable and maintainable. These helpers should be be made as easy
+to inline as possible by the JVM whenever possible.
+
+An obfuscation helper to access an obfuscated item may be as simple as something
+like this:
+
 ```java
 public final int getStuckArrows() { return this.bY(); } // Paper - OBFHELPER
 ```
-Or it may be as complex as forwarding an entire method so that it can be overriden later:
+
+Or it may be as complex as forwarding an entire method so that it can be
+overridden later:
+
 ```java
 public boolean be() {
     // Paper start - OBFHELPER
@@ -210,32 +361,156 @@ public boolean pushedByWater() {
     return true;
 }
 ```
-While they may not always be done in exactly the same way each time, the general goal is always to improve readability and maintainability, so use your best judgement.
+
+While they may not always be done in exactly the same way, the general goal is
+always to improve readability and maintainability. Use your best judgment and do
+what fits best in your situation.
 
 ## Configuration files
-To use a configurable value in your patch, add a new entry in either ```PaperConfig``` or ```PaperWorldConfig```. Use the former if a value must remain the same throughout all worlds, or the latter if it can change between worlds. The latter is preferred whenever possible.
 
-### PaperConfig example:
+To use a configurable value in your patch, add a new entry in either the
+`PaperConfig` or `PaperWorldConfig` classes. Use `PaperConfig` if a value
+must remain the same throughout all worlds, or the latter if it can change
+between worlds. World-specific configuration options are preferred whenever
+possible.
+
+### PaperConfig example
+
 ```java
 public static boolean saveEmptyScoreboardTeams = false;
 private static void saveEmptyScoreboardTeams() {
+    // This is called automatically!
+    // The name also doesn't matter.
     saveEmptyScoreboardTeams = getBoolean("settings.save-empty-scoreboard-teams", false);
 }
 ```
-Notice that the field is always public, but the setter is always private. This is important to the way the configuration generation system works. To access this value, reference it as you would any other static value:
+
+Notice that the field is always public, but the setter is always private. This
+is important to the way the configuration generation system works. To access
+this value, reference it as you would any other static value:
+
 ```java
 if (!PaperConfig.saveEmptyScoreboardTeams) {
 ```
 
-### PaperWorldConfig example:
+It is often preferred that you use the fully qualified name for the
+configuration class when accessing it, like so:
+`com.destroystokyo.paper.PaperConfig.valueHere`.  
+If this is not done, a developer for Paper might fix that for you before
+merging, but it's always nice if you make it a habit where you only need 1-2
+lines changed.
+
+### PaperWorldConfig example
+
 ```java
 public boolean useInhabitedTime = true;
 private void useInhabitedTime() {
+    // This is called automatically!
+    // The name also doesn't matter.
     useInhabitedTime = getBoolean("use-chunk-inhabited-timer", true);
 }
 ```
-Again, notice that the field is always public, but the setter is always private. To access this value, you'll need an instance of the ```net.minecraft.World``` object:
+
+Again, notice that the field is always public, but the setter is always private.
+To access this value, you'll need an instance of the `net.minecraft.World`
+object:
 
 ```java
 return this.world.paperConfig.useInhabitedTime ? this.w : 0;
 ```
+
+## Frequently Asked Questions
+
+### I can't find the NMS file I need!
+
+By default, Paper (and upstream) only import files we make changes to. If you
+would like to make changes to a file that isn't present in `Paper-Server`'s
+source directory, you just need to add it to our import script ran during the
+patching process.
+
+1. Save (rebuild) any patches you are in the middle of working on! Their
+progress will be lost if you do not;
+1. Identify the name(s) of the file(s) you want to import.
+   - A complete list of all possible file names can be found at
+   `./work/Minecraft/$MCVER/spigot/net/minecraft/server`. You might find
+   [MiniMappingViewer] very useful to find the file you need.
+1. Open the file at `./scripts/importmcdev.sh` and add the name of your file to
+the script. Skip to the 2nd last header and follow the instructions there;
+1. Re-patch the server `./paper patch`;
+1. Edit away!
+
+> ❗ This change is temporary! **DO NOT COMMIT CHANGES TO THIS FILE!**  
+> Once you have made your changes to the new file, and rebuilt patches, you may
+> undo your changes to `importmcdev.sh`.
+
+Any file modified in a patch file gets automatically imported, so you only need
+this temporarily to import it to create the first patch.
+
+To undo your changes to the file, type `git checkout scripts/importmcdev.sh`.
+
+### Where can I learn how to name method/field?
+
+For most cases, it is preferred if you use [yarn], as their license works with
+Paper's license. If you can't do that, [MiniMappingViewer] is always around to
+provide you with more of a general idea, *but* you cannot use the Mojang names
+for more than understanding the code.
+
+[yarn] is in general more thorough than Mojang's own mappings, as they include
+method arguments as well, whereas Mojang's do not. If you need local variables
+to understand the code, you might be more lucky with ModCoderPack.
+
+For more information on the Mojang name licensing issues, check this out:
+<https://cpw.github.io/MinecraftMappingData.html>
+
+### My commit doesn't need a build, what do I do?
+
+Well, quite simple: You add `[CI-SKIP]` to the start of your commit subject.
+
+This case most often applies to changes to files like `README.md`, this very
+file (`CONTRIBUTING.md`), the `LICENSE.md` file, and so forth.
+
+### Patching and building is *really* slow, what can I do?
+
+This only applies if you're running Windows. If you're running a prior Windows
+release, either update to Windows 10 or move to macOS/Linux/BSD.
+
+In order to speed up patching process on Windows, it's recommended you get WSL
+2. This is available in Windows 10 v2004, build 19041 or higher. (You can check
+your version by running `winver` in the run window (Windows key + R)). If you're
+out of date, update your system with the
+[Windows Update Assistant](https://www.microsoft.com/en-us/software-download/windows10).
+
+To setup WSL 2, follow the information here:
+<https://docs.microsoft.com/en-us/windows/wsl/install-win10>
+
+You will most likely want to use the Ubuntu apps. Once it's set up, install the
+required tools with `sudo apt-get update && sudo apt-get install $TOOL_NAMES
+-y`. Replace `$TOOL_NAMES` with the packages found in the
+[requirements](#requirements). You can now clone the repository and do
+everything like usual.
+
+> ❗ Do not use the `/mnt/` directory in WSL! Instead, mount the WSL directories
+> in Windows like described here:
+> <https://www.howtogeek.com/426749/how-to-access-your-linux-wsl-files-in-windows-10/>
+
+### I wrote some API, how do I use it in Paper-Server?
+
+To install the API to your local maven repository, do the following:
+
+- Enter the API directory by running `./paper api`;
+- Run `mvn install`.
+   - If you are working on a patch without much care for whether the tests
+   pass, you can instead run `mvn install -DskipTests`. Do not PR changes
+   without running tests first.
+   - If a test failed, you have to identify the failing tests by scrolling up a
+   couple lines (i.e. around 50-200). You should find it fairly quickly.
+   - If you later need to use the Paper-API, you might want to remove the jar
+   from your local maven repository.  
+   If you use Windows and don't usually build using WSL, you might not need to
+   do this.
+
+You can now use the API in your plugin to test it before PRing. You will also
+need to do this to build the Server with the implemented API.
+
+[MiniMappingViewer]: https://minidigger.github.io/MiniMappingViewer/
+[yarn]: https://github.com/FabricMC/yarn