diff --git a/biome.json b/biome.json
index 5de4567ff7..9a06585594 100644
--- a/biome.json
+++ b/biome.json
@@ -2,7 +2,7 @@
   "$schema": "https://biomejs.dev/schemas/1.9.1/schema.json",
   "files": {
     "include": ["runtime"],
-    "ignore": ["runtime/zstd.ts"]
+    "ignore": ["runtime/js/zstd.ts"]
   },
   "formatter": {
     "enabled": true,
diff --git a/compiler/lib-runtime-files/dune b/compiler/lib-runtime-files/dune
index e9e77ae73c..5742162d2a 100644
--- a/compiler/lib-runtime-files/dune
+++ b/compiler/lib-runtime-files/dune
@@ -7,7 +7,7 @@
  (target files.ml)
  (deps
   gen/gen.exe
-  (glob_files ../../runtime/*.js))
+  (glob_files ../../runtime/js/*.js))
  (action
   (with-stdout-to
    %{target}
diff --git a/runtime/array.js b/runtime/js/array.js
similarity index 100%
rename from runtime/array.js
rename to runtime/js/array.js
diff --git a/runtime/backtrace.js b/runtime/js/backtrace.js
similarity index 100%
rename from runtime/backtrace.js
rename to runtime/js/backtrace.js
diff --git a/runtime/bigarray.js b/runtime/js/bigarray.js
similarity index 100%
rename from runtime/bigarray.js
rename to runtime/js/bigarray.js
diff --git a/runtime/bigstring.js b/runtime/js/bigstring.js
similarity index 100%
rename from runtime/bigstring.js
rename to runtime/js/bigstring.js
diff --git a/runtime/blake2.js b/runtime/js/blake2.js
similarity index 100%
rename from runtime/blake2.js
rename to runtime/js/blake2.js
diff --git a/runtime/compare.js b/runtime/js/compare.js
similarity index 100%
rename from runtime/compare.js
rename to runtime/js/compare.js
diff --git a/runtime/domain.js b/runtime/js/domain.js
similarity index 100%
rename from runtime/domain.js
rename to runtime/js/domain.js
diff --git a/runtime/dune b/runtime/js/dune
similarity index 100%
rename from runtime/dune
rename to runtime/js/dune
diff --git a/runtime/dynlink.js b/runtime/js/dynlink.js
similarity index 100%
rename from runtime/dynlink.js
rename to runtime/js/dynlink.js
diff --git a/runtime/effect.js b/runtime/js/effect.js
similarity index 100%
rename from runtime/effect.js
rename to runtime/js/effect.js
diff --git a/runtime/fail.js b/runtime/js/fail.js
similarity index 100%
rename from runtime/fail.js
rename to runtime/js/fail.js
diff --git a/runtime/format.js b/runtime/js/format.js
similarity index 100%
rename from runtime/format.js
rename to runtime/js/format.js
diff --git a/runtime/fs.js b/runtime/js/fs.js
similarity index 100%
rename from runtime/fs.js
rename to runtime/js/fs.js
diff --git a/runtime/fs_fake.js b/runtime/js/fs_fake.js
similarity index 100%
rename from runtime/fs_fake.js
rename to runtime/js/fs_fake.js
diff --git a/runtime/fs_node.js b/runtime/js/fs_node.js
similarity index 100%
rename from runtime/fs_node.js
rename to runtime/js/fs_node.js
diff --git a/runtime/gc.js b/runtime/js/gc.js
similarity index 100%
rename from runtime/gc.js
rename to runtime/js/gc.js
diff --git a/runtime/graphics.js b/runtime/js/graphics.js
similarity index 100%
rename from runtime/graphics.js
rename to runtime/js/graphics.js
diff --git a/runtime/hash.js b/runtime/js/hash.js
similarity index 100%
rename from runtime/hash.js
rename to runtime/js/hash.js
diff --git a/runtime/ieee_754.js b/runtime/js/ieee_754.js
similarity index 100%
rename from runtime/ieee_754.js
rename to runtime/js/ieee_754.js
diff --git a/runtime/int64.js b/runtime/js/int64.js
similarity index 100%
rename from runtime/int64.js
rename to runtime/js/int64.js
diff --git a/runtime/internalMod.js b/runtime/js/internalMod.js
similarity index 100%
rename from runtime/internalMod.js
rename to runtime/js/internalMod.js
diff --git a/runtime/ints.js b/runtime/js/ints.js
similarity index 100%
rename from runtime/ints.js
rename to runtime/js/ints.js
diff --git a/runtime/io.js b/runtime/js/io.js
similarity index 100%
rename from runtime/io.js
rename to runtime/js/io.js
diff --git a/runtime/jslib.js b/runtime/js/jslib.js
similarity index 100%
rename from runtime/jslib.js
rename to runtime/js/jslib.js
diff --git a/runtime/jslib_js_of_ocaml.js b/runtime/js/jslib_js_of_ocaml.js
similarity index 100%
rename from runtime/jslib_js_of_ocaml.js
rename to runtime/js/jslib_js_of_ocaml.js
diff --git a/runtime/lexing.js b/runtime/js/lexing.js
similarity index 100%
rename from runtime/lexing.js
rename to runtime/js/lexing.js
diff --git a/runtime/marshal.js b/runtime/js/marshal.js
similarity index 100%
rename from runtime/marshal.js
rename to runtime/js/marshal.js
diff --git a/runtime/md5.js b/runtime/js/md5.js
similarity index 100%
rename from runtime/md5.js
rename to runtime/js/md5.js
diff --git a/runtime/mlBytes.js b/runtime/js/mlBytes.js
similarity index 100%
rename from runtime/mlBytes.js
rename to runtime/js/mlBytes.js
diff --git a/runtime/nat.js b/runtime/js/nat.js
similarity index 100%
rename from runtime/nat.js
rename to runtime/js/nat.js
diff --git a/runtime/obj.js b/runtime/js/obj.js
similarity index 100%
rename from runtime/obj.js
rename to runtime/js/obj.js
diff --git a/runtime/parsing.js b/runtime/js/parsing.js
similarity index 100%
rename from runtime/parsing.js
rename to runtime/js/parsing.js
diff --git a/runtime/prng.js b/runtime/js/prng.js
similarity index 100%
rename from runtime/prng.js
rename to runtime/js/prng.js
diff --git a/runtime/runtime_events.js b/runtime/js/runtime_events.js
similarity index 100%
rename from runtime/runtime_events.js
rename to runtime/js/runtime_events.js
diff --git a/runtime/stdlib.js b/runtime/js/stdlib.js
similarity index 100%
rename from runtime/stdlib.js
rename to runtime/js/stdlib.js
diff --git a/runtime/stdlib_modern.js b/runtime/js/stdlib_modern.js
similarity index 100%
rename from runtime/stdlib_modern.js
rename to runtime/js/stdlib_modern.js
diff --git a/runtime/str.js b/runtime/js/str.js
similarity index 100%
rename from runtime/str.js
rename to runtime/js/str.js
diff --git a/runtime/sync.js b/runtime/js/sync.js
similarity index 100%
rename from runtime/sync.js
rename to runtime/js/sync.js
diff --git a/runtime/sys.js b/runtime/js/sys.js
similarity index 100%
rename from runtime/sys.js
rename to runtime/js/sys.js
diff --git a/runtime/toplevel.js b/runtime/js/toplevel.js
similarity index 100%
rename from runtime/toplevel.js
rename to runtime/js/toplevel.js
diff --git a/runtime/unix.js b/runtime/js/unix.js
similarity index 100%
rename from runtime/unix.js
rename to runtime/js/unix.js
diff --git a/runtime/weak.js b/runtime/js/weak.js
similarity index 100%
rename from runtime/weak.js
rename to runtime/js/weak.js
diff --git a/runtime/zstd.js b/runtime/js/zstd.js
similarity index 100%
rename from runtime/zstd.js
rename to runtime/js/zstd.js
diff --git a/runtime/zstd.ts b/runtime/js/zstd.ts
similarity index 100%
rename from runtime/zstd.ts
rename to runtime/js/zstd.ts