Implement runtime priorities

api/src/bin/pistond.js

@@ -43,7 +43,22 @@ expressWs(app);
             `nix eval --json ${config.flake_path}#pistonRuntimeSets.${config.runtime_set} --apply builtins.attrNames`
         )
         .toString();
-    const runtime_names = JSON.parse(runtimes_data);
+    const runtime_names_unordered = JSON.parse(runtimes_data);
+
+    const priorities_data = cp
+        .execSync(
+            `nix eval --json ${config.flake_path}#pistonRuntimePriorities`
+        )
+        .toString();
+    const priorities = JSON.parse(priorities_data).filter(runtime =>
+        runtime_names_unordered.includes(runtime)
+    );
+    const runtime_names = [
+        ...priorities,
+        ...runtime_names_unordered.filter(
+            runtime => !priorities.includes(runtime)
+        ),
+    ];
 
     logger.info('Loading the runtimes from the flakes');
     const runtimes = runtime_names.map(runtime_name => {

flake.nix

@@ -65,6 +65,7 @@
       "bash-only" = runtimeList ["bash"];
       "none" = { };
     };
+    pistonRuntimePriorities = import ./runtimes/priorities;
 
     legacyPackages."${system}" = rec {
       nosocket = (import ./nosocket { inherit pkgs; }).package;

runtimes/priorities/default.nix

@@ -1,7 +1,7 @@
 [
     "node-javascript"
-    "python2"
     "python3"
+    "python2"
     "bash"
     "clojure"
     "cobol-gnu-cobol"