diff --git a/src/main/java/net/fabricmc/loom/task/GenIdeaProjectTask.java b/src/main/java/net/fabricmc/loom/task/GenIdeaProjectTask.java
index 77e17bf..f3c9f6f 100644
--- a/src/main/java/net/fabricmc/loom/task/GenIdeaProjectTask.java
+++ b/src/main/java/net/fabricmc/loom/task/GenIdeaProjectTask.java
@@ -140,7 +140,7 @@ public class GenIdeaProjectTask extends DefaultTask {
 		ideaClient.configName = "Minecraft Client";
 		ideaClient.runDir = "file://$PROJECT_DIR$/" + extension.runDir;
 		ideaClient.vmArgs = "-Djava.library.path=" + Constants.MINECRAFT_NATIVES.get(extension).getAbsolutePath() + " -Dfabric.development=true";
-		ideaClient.programArgs = "--tweakClass " + Constants.FABRIC_CLIENT_TWEAKER + " --assetIndex " + version.assetIndex.id + " --assetsDir " + new File(extension.getUserCache(), "assets-" + extension.version).getAbsolutePath();
+		ideaClient.programArgs = "--tweakClass " + Constants.FABRIC_CLIENT_TWEAKER + " --assetIndex " + version.assetIndex.id + " --assetsDir \"" + new File(extension.getUserCache(), "assets-" + extension.version).getAbsolutePath() + "\" --fabricMappingFile \"" + Constants.MAPPINGS_TINY.get(extension).getAbsolutePath() + "\"";
 
 		runManager.appendChild(ideaClient.genRuns(runManager));
 
@@ -150,7 +150,7 @@ public class GenIdeaProjectTask extends DefaultTask {
 		ideaServer.configName = "Minecraft Server";
 		ideaServer.runDir = "file://$PROJECT_DIR$/" + extension.runDir;
 		ideaServer.vmArgs = "-Dfabric.development=true";
-		ideaServer.programArgs = "--tweakClass " + Constants.FABRIC_SERVER_TWEAKER;
+		ideaServer.programArgs = "--tweakClass " + Constants.FABRIC_SERVER_TWEAKER + " --fabricMappingFile \"" + Constants.MAPPINGS_TINY.get(extension).getAbsolutePath() + "\"";
 
 		runManager.appendChild(ideaServer.genRuns(runManager));
 
diff --git a/src/main/java/net/fabricmc/loom/task/RunClientTask.java b/src/main/java/net/fabricmc/loom/task/RunClientTask.java
index 9c760f4..370c87e 100644
--- a/src/main/java/net/fabricmc/loom/task/RunClientTask.java
+++ b/src/main/java/net/fabricmc/loom/task/RunClientTask.java
@@ -70,7 +70,7 @@ public class RunClientTask extends JavaExec {
 
 		classpath(libs);
 
-		args("--tweakClass", Constants.FABRIC_CLIENT_TWEAKER, "--assetIndex", version.assetIndex.id, "--assetsDir", new File(extension.getUserCache(), "assets-" + extension.version).getAbsolutePath());
+		args("--tweakClass", Constants.FABRIC_CLIENT_TWEAKER, "--assetIndex", version.assetIndex.id, "--assetsDir", new File(extension.getUserCache(), "assets-" + extension.version).getAbsolutePath(), "--fabricMappingFile", Constants.MAPPINGS_TINY.get(extension).getAbsolutePath());
 
 		setWorkingDir(new File(getProject().getRootDir(), "run"));
 
diff --git a/src/main/java/net/fabricmc/loom/task/RunServerTask.java b/src/main/java/net/fabricmc/loom/task/RunServerTask.java
index 580dac9..418643b 100644
--- a/src/main/java/net/fabricmc/loom/task/RunServerTask.java
+++ b/src/main/java/net/fabricmc/loom/task/RunServerTask.java
@@ -65,7 +65,7 @@ public class RunServerTask extends JavaExec {
 		libs.add(Constants.MINECRAFT_FINAL_JAR.get(extension).getAbsolutePath());
 		classpath(libs);
 
-		args("--tweakClass", Constants.FABRIC_SERVER_TWEAKER);
+		args("--tweakClass", Constants.FABRIC_SERVER_TWEAKER,  "--fabricMappingFile", Constants.MAPPINGS_TINY.get(extension).getAbsolutePath());
 
 		setWorkingDir(new File(getProject().getRootDir(), "run"));