add build instructions

README.md

@@ -53,3 +53,38 @@ Status Definitions:
 * ✅ Supported: This version is fully supported and will receive all new features, fixes, and updates (where possible)
 * ⚠️ Critical fixes only: This version will receive only critical crash and security fixes, as well as minor features where they can be easily cherry-picked
 * ❌ Unsupported: This version will receive no future updates, except for critical security fixes
+
+## Build and Test Instructions
+
+Thermoo is built using [Gradle](https://gradle.org/) with the [Fabric Loom Gradle plugin](https://github.com/FabricMC/fabric-loom).
+
+To make a production build of Thermoo, run the following command:
+```bash
+gradlew build
+# On windows add a ./
+./gradlew build
+```
+The built jars will appear in `/build/libs/`, and will include a regular jar, a `-sources` jar, and a `-javadoc` jar. To
+play Thermoo, install [Fabric API](https://github.com/FabricMC/fabric) and[Cardinal Components API](https://github.com/Ladysnake/Cardinal-Components-API)
+and install the regular into your Minecraft `/mods` folder.
+
+To run Thermoo's unit tests, run the following command:
+```bash
+gradlew test
+```
+
+Thermoo also includes some game tests, to automatically run them use the following command:
+```bash
+gradlew runGametest
+```
+
+Finally, you can manually test Thermoo in a Minecraft environment using the test mod:
+```bash
+gradlew runTestmodClient
+```
+This will launch a Minecraft instance with a test mod that includes implements Thermoo's API features for testing. 
+
+If you instead want a clean test Minecraft instance with no gameplay modifications can be run with the following:
+```bash
+gradlew runClient
+```