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README.md

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 # bareiron
-Minimalist Minecraft server for memory-restrictive embedded systems
+Minimalist Minecraft server for memory-restrictive embedded systems.
+
+The goal of this project is to enable hosting Minecraft servers on very weak devices, such as the ESP32. The project's priorities are, in order: **memory usage**, **performance**, and **features**. Because of this, compliance with vanilla Minecraft is not guaranteed, nor is it a goal of the project.
+
+## Quick start
+Before compiling, you'll need to dump registry data from a vanilla Minecraft server. Create a folder called `notchian` here, and put a Minecraft server JAR in it. Then, follow [this guide](https://minecraft.wiki/w/Minecraft_Wiki:Projects/wiki.vg_merge/Data_Generators) to dump all of the registries. Finally, run `build_registries.js` with `node`, `bun`, or `deno`.
+
+- To target Linux, install `gcc` and run `build.sh`
+- To target an ESP variant, set up a PlatformIO project and clone this repository on top of it.
+
+## Configuration
+Most user-friendly configuration options are available in `include/globals.h`, including WiFi credentials for embedded setups. Of course, many more things can be configured by editing the source code.
+
+## Non-volatile storage (optional)
+This section applies to those who target ESP variants and wish to persist world data after a shutdown. *This is not necessary on PC platforms*, as world and player data is written to `world.bin` by default.
+
+The simplest way to accomplish this is to set up LittleFS in PlatformIO and comment out the `#ifndef` surrounding `SYNC_WORLD_TO_DISK` in `globals.h`. Since flash writes are typically slow and blocking, you'll likely want to uncomment `DISK_SYNC_BLOCKS_ON_INTERVAL`. Depending on the flash size of your board, you may also have to decrease `MAX_BLOCK_CHANGES`, so that the world data fits in your LittleFS partition.
+
+If using an SD card module or other virtual file system, you'll have to implement the filesystem setup routine on your own. The built-in serializer should still work though, as it uses POSIX filesystem calls.
+
+Alternatively, if you can't set up a file system, you can dump and upload world data over TCP. This can be enabled by uncommenting `DEV_ENABLE_BEEF_DUMPS` in `globals.h`. *Note: this system implements no security or authentication.* With this option enabled, anyone with access to the server can upload arbitrary world data.
+
+## Contribution
+- Create issues and discuss with the maintainer(s) before making pull requests.
+- Follow the existing code style. Ensure that your changes fit in with the surrounding code, even if you disagree with the style. Pull requests with inconsistent style will be nitpicked.