diff --git a/bin/build.ml b/bin/build.ml
index 901f5bd3102..1f1b7d15e6b 100644
--- a/bin/build.ml
+++ b/bin/build.ml
@@ -98,8 +98,11 @@ let poll_handling_rpc_build_requests ~(common : Common.t) ~config =
          match kind with
          | Build targets ->
            Target.interpret_targets (Common.root common) config setup targets
-         | Runtest dir_or_cram_test_paths ->
-           Runtest_common.make_request ~dir_or_cram_test_paths ~to_cwd:root.to_cwd setup
+         | Runtest test_paths ->
+           Runtest_common.make_request
+             ~contexts:setup.contexts
+             ~to_cwd:root.to_cwd
+             ~test_paths
        in
        run_build_system ~common ~request, outcome)
 ;;
diff --git a/bin/runtest.ml b/bin/runtest.ml
index 28124e2e577..821986b84cc 100644
--- a/bin/runtest.ml
+++ b/bin/runtest.ml
@@ -36,17 +36,15 @@ let runtest_info =
 let runtest_term =
   let name = Arg.info [] ~docv:"TEST" in
   let+ builder = Common.Builder.term
-  and+ dir_or_cram_test_paths = Arg.(value & pos_all string [ "." ] name) in
+  and+ test_paths = Arg.(value & pos_all string [ "." ] name) in
   let common, config = Common.init builder in
   match Dune_util.Global_lock.lock ~timeout:None with
   | Ok () ->
-    Build.run_build_command
-      ~common
-      ~config
-      ~request:
-        (Runtest_common.make_request
-           ~dir_or_cram_test_paths
-           ~to_cwd:(Common.root common).to_cwd)
+    Build.run_build_command ~common ~config ~request:(fun setup ->
+      Runtest_common.make_request
+        ~contexts:setup.contexts
+        ~to_cwd:(Common.root common).to_cwd
+        ~test_paths)
   | Error lock_held_by ->
     Scheduler.go_without_rpc_server ~common ~config (fun () ->
       let open Fiber.O in
@@ -56,7 +54,7 @@ let runtest_term =
         ~lock_held_by
         builder
         Dune_rpc.Procedures.Public.runtest
-        dir_or_cram_test_paths
+        test_paths
       >>| Rpc.Rpc_common.wrap_build_outcome_exn ~print_on_success:true)
 ;;
 
diff --git a/bin/runtest_common.ml b/bin/runtest_common.ml
index c235a30ae76..cda81f5101c 100644
--- a/bin/runtest_common.ml
+++ b/bin/runtest_common.ml
@@ -75,9 +75,8 @@ let disambiguate_test_name path =
         | None -> explain_unsuccessful_search path ~parent_dir))
 ;;
 
-let make_request ~dir_or_cram_test_paths ~to_cwd (setup : Import.Main.build_system) =
-  let contexts = setup.contexts in
-  List.map dir_or_cram_test_paths ~f:(fun dir ->
+let make_request ~contexts ~to_cwd ~test_paths =
+  List.map test_paths ~f:(fun dir ->
     let dir = Path.of_string dir |> Path.Expert.try_localize_external in
     let open Action_builder.O in
     let* contexts, alias_kind =
diff --git a/bin/runtest_common.mli b/bin/runtest_common.mli
index b88a10e4914..877d2cde0fe 100644
--- a/bin/runtest_common.mli
+++ b/bin/runtest_common.mli
@@ -1,10 +1,7 @@
 open Import
 
-(** [make_request ~dir_or_cram_test_paths ~to_cwd] returns a function suitable
-    for passing to [Build_cmd.run_build_system] which runs the tests referred
-    to by the elements of [dir_or_cram_test_paths]. *)
 val make_request
-  :  dir_or_cram_test_paths:string list
+  :  contexts:Context.t list
   -> to_cwd:string list
-  -> Dune_rules.Main.build_system
+  -> test_paths:string list
   -> unit Action_builder.t