Created a basic config so people can use this in production.

gradle.properties

@@ -7,7 +7,7 @@ yarn_mappings       = 1.16.4+build.1
 loader_version      = 0.10.6+build.214
 
 # Mod Properties
-mod_version         = 0.0.3
+mod_version         = 0.1.0
 maven_group         = dev.hephaestus
 archives_base_name  = sax
 

src/main/java/dev/hephaestus/sax/SAX.java

@@ -22,6 +22,8 @@ public static Identifier id(String... path) {
 
     @Override
     public void onInitialize() {
+        Config.load();
+
         for (Map.Entry<Block, Block> entry : Config.HIDDEN.entrySet()) {
             FibLib.Blocks.register(new HideOccludedOre(entry.getKey(), entry.getValue()));
         }

src/main/java/dev/hephaestus/sax/server/Config.java

@@ -1,12 +1,26 @@
 package dev.hephaestus.sax.server;
 
+import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
+import net.fabricmc.loader.api.FabricLoader;
 import net.minecraft.block.Block;
 import net.minecraft.block.Blocks;
+import net.minecraft.util.Identifier;
+import net.minecraft.util.JsonHelper;
+import net.minecraft.util.registry.Registry;
 
+import java.io.IOException;
+import java.io.Writer;
+import java.nio.file.Files;
+import java.nio.file.Path;
 import java.util.HashMap;
+import java.util.Map;
 
-// Dummy config for now
+// Simple config for now
 public class Config {
+	private static final Gson GSON = new GsonBuilder().setPrettyPrinting().create();
 	public static final HashMap<Block, Block> HIDDEN = new HashMap<>();
 
 	static {
@@ -19,4 +33,39 @@ public class Config {
 		HIDDEN.put(Blocks.MOSSY_COBBLESTONE, Blocks.STONE);
 		HIDDEN.put(Blocks.SPAWNER, Blocks.CAVE_AIR);
 	}
+
+	public static void load() {
+		Path configDir = FabricLoader.getInstance().getConfigDir().normalize().resolve("sax");
+		Path configFile = configDir.resolve("blocks.json");
+
+		try {
+			if (!Files.exists(configFile)) {
+				Files.createDirectories(configDir);
+
+				JsonObject jsonObject = new JsonObject();
+
+				for (Map.Entry<Block, Block> entry : HIDDEN.entrySet()) {
+					jsonObject.addProperty(
+						Registry.BLOCK.getId(entry.getKey()).toString(),
+						Registry.BLOCK.getId(entry.getValue()).toString()
+					);
+				}
+
+				Writer writer = Files.newBufferedWriter(configFile);
+				writer.write(GSON.toJson(jsonObject));
+				writer.close();
+			} else {
+				HIDDEN.clear();
+
+				for (Map.Entry<String, JsonElement> element : JsonHelper.deserialize(Files.newBufferedReader(configFile)).entrySet()) {
+					HIDDEN.put(
+						Registry.BLOCK.get(new Identifier(element.getKey())),
+						Registry.BLOCK.get(new Identifier(element.getValue().getAsString()))
+					);
+				}
+			}
+		} catch (IOException e) {
+			e.printStackTrace();
+		}
+	}
 }