tuned signature;

--- a/src/Pure/Tools/build_job.scala	Wed May 11 09:53:29 2022 +0200
+++ b/src/Pure/Tools/build_job.scala	Wed May 11 10:42:24 2022 +0200
@@ -7,8 +7,6 @@
 package isabelle
 
 
-import java.util.HashMap
-
 import scala.collection.mutable
 
 
@@ -215,8 +213,9 @@
       val base = deps(parent)
       val result_base = deps(session_name)
 
-      val env = new HashMap(Isabelle_System.settings())
-      env.put("ISABELLE_ML_DEBUGGER", options.bool("ML_debugger").toString)
+      val env =
+        Isabelle_System.settings(
+          List("ISABELLE_ML_DEBUGGER" -> options.bool("ML_debugger").toString))
 
       val is_pure = Sessions.is_pure(session_name)
 

--- a/src/Tools/VSCode/src/vscode_main.scala	Wed May 11 09:53:29 2022 +0200
+++ b/src/Tools/VSCode/src/vscode_main.scala	Wed May 11 10:42:24 2022 +0200
@@ -19,7 +19,7 @@
     Path.explode("$ISABELLE_VSCODE_SETTINGS/server.log").expand
 
   def run_vscodium(args: List[String],
-    environment: Iterable[(String, String)] = Nil,
+    environment: List[(String, String)] = Nil,
     options: List[String] = Nil,
     logic: String = "",
     logic_ancestor: String = "",
@@ -49,11 +49,11 @@
         (if (server_log) Some(server_log_path.absolute.implode) else None)) ++
       JSON.optional("verbose" -> proper_bool(verbose))
 
-    val env = new java.util.HashMap(Isabelle_System.settings())
-    for ((a, b) <- environment) env.put(a, b)
-    env.put("ISABELLE_VSCODIUM_ARGS", JSON.Format(args_json))
-    env.put("ISABELLE_VSCODIUM_APP", platform_path("$ISABELLE_VSCODIUM_RESOURCES/vscodium"))
-    env.put("ELECTRON_RUN_AS_NODE", "1")
+    val env =
+      Isabelle_System.settings(environment ::: List(
+        "ISABELLE_VSCODIUM_ARGS" -> JSON.Format(args_json),
+        "ISABELLE_VSCODIUM_APP" -> platform_path("$ISABELLE_VSCODIUM_RESOURCES/vscodium"),
+        "ELECTRON_RUN_AS_NODE" -> "1"))
 
     val electron = Isabelle_System.getenv("ISABELLE_VSCODIUM_ELECTRON")
     if (electron.isEmpty) {