diff --git a/changes/ludic-build-http.md b/changes/ludic-build-http.md
new file mode 100644
index 00000000..da86e5ad
--- /dev/null
+++ b/changes/ludic-build-http.md
@@ -0,0 +1,8 @@
+bump: patch
+type: fix
+**`ludic build` links `Http.*`** — a program that uses the HTTP client builds through the CLI.
+
+`compile_app` linked the OpenGL backend when a program named `@lgl_*` but never
+`runtime/native/http.ll` and Foundation for `@hs_*`, so a `Http.*` program failed to link
+under `ludic build` / `ludic run` while `ludicc -o` built it. It now links them the same way,
+windowed and headless.
diff --git a/tools/ludic-cli/build.ludic b/tools/ludic-cli/build.ludic
index 3ecedcb9..381bb954 100644
--- a/tools/ludic-cli/build.ludic
+++ b/tools/ludic-cli/build.ludic
@@ -36,7 +36,7 @@ function compile_app(src: pointer, out: pointer, mode: int, save: bool) -> bool
 
   if mode == 2 {
     if not shq(`{ludicc()} --headless {src} --emit-llvm -o {ll}`) { return false }
-    if not shq(`{cc()} -O2 {ll}{gl_link_flags(ll)}{pbf} -o {out}`) { return false }
+    if not shq(`{cc()} -O2 {ll}{gl_link_flags(ll)}{http_link_flags(ll)}{pbf} -o {out}`) { return false }
     if not save { run(`rm -f {ll}`) }
     return true
   }
@@ -46,7 +46,7 @@ function compile_app(src: pointer, out: pointer, mode: int, save: bool) -> bool
   # canonical `ludicc -o` path links it only when Audio.* is used.
   let cocoa = `{home}runtime/native/cocoa.ll`
   let audio = `{home}runtime/native/audio.ll`
-  if not shq(`{cc()} -O2 {ll} {cocoa} {audio} -framework Cocoa -Wl,-needed_framework,GameController -Wl,-needed_framework,AVFoundation -Wl,-rpath,@loader_path{gl_link_flags(ll)}{pbf} -o {out}`) { return false }
+  if not shq(`{cc()} -O2 {ll} {cocoa} {audio} -framework Cocoa -Wl,-needed_framework,GameController -Wl,-needed_framework,AVFoundation -Wl,-rpath,@loader_path{gl_link_flags(ll)}{http_link_flags(ll)}{pbf} -o {out}`) { return false }
   if not save { run(`rm -f {ll}`) }
   return true
 }
@@ -59,6 +59,14 @@ function gl_link_flags(ll: pointer) -> pointer {
   return ` {home}runtime/native/gl.ll {home}runtime/native/gl_thunks.ll -framework OpenGL`
 }
 
+# A program that uses Http.* calls the @hs_* transport; link http.ll and Foundation only
+# then, in both modes, as `ludicc -o` does (selfhost/main.ludic). Without it a Http.*
+# program built through `ludic build` failed to link on every hs_* symbol.
+function http_link_flags(ll: pointer) -> pointer {
+  if not shq(`grep -q "@hs_" {ll}`) { return "" }
+  return ` {ludic_home()}runtime/native/http.ll -Wl,-needed_framework,Foundation`
+}
+
 # the directory part of a path, without the trailing '/' ("" when there is none)
 function dir_of_path(p: pointer) -> pointer {
   var last = -1
diff --git a/tools/ludic-cli/test.ludic b/tools/ludic-cli/test.ludic
index 62713b86..cc0ac8fb 100644
--- a/tools/ludic-cli/test.ludic
+++ b/tools/ludic-cli/test.ludic
@@ -679,6 +679,7 @@ function cmd_dev_test() -> int {
   feat_case("library/input_auto", "llq", "2", "input_auto.ludic (#83 the frame loop auto-commits the device layer: Input.active fires with no manual Input.poll)")
   feat_case("library/input_edge", "xkkxq", "0 11 1 100 0", "input_edge.ludic (#87 Input.key_pressed/key_released edges fire on the transition frame; no double-commit under the frame loop)")
   feat_case("library/input_movement", "", "1 0 -1 -1 0", "input_movement.ludic (#79 Input.axis_i turns WASD into a -1/0/1 movement intent, no bool->int glue)")
+  feat_case("library/input_arrows", "", "128 129 130 131 1 0 -1 1 0", "input_arrows.ludic (Key.Up/Down/Left/Right are the held set's 128-131: key_down and move_i take the arrows)")
   feat_case("library/audio", "", "0 0 0 0 1", "audio.ludic (#22 Audio.* load/play/music/volume/pitch/stop/is_playing — headless no-op)")
   # #6 Http.* — the client links Foundation (macOS-only), so build it through the
   # canonical `ludicc -o` path (which wires the framework) and gate on Darwin. The
@@ -689,6 +690,13 @@ function cmd_dev_test() -> int {
       if (got == "200 1 5 hello 42 text/plain 404 0") { ok("http.ludic (#6 Http.parse/status/ok/text/header — pure response parser)") }
       else { bad2("http.ludic", `got [{got}]`) }
     } else { bad2("http.ludic build", capture_line(`tail -1 {tmp_dir()}/http.out`)) }
+    # and through `ludic build`, which is how a project builds: compile_app used to link
+    # gl.ll when a program named @lgl_* but never http.ll for @hs_*, so this failed to link
+    if shq(`LUDIC_HOME=. bin/ludic build examples/library/http.ludic --headless -o {tmp_dir()}/http_lb > {tmp_dir()}/http_lb.out 2>&1`) {
+      let got2 = capture_line(`{tmp_dir()}/http_lb < /dev/null`)
+      if (got2 == "200 1 5 hello 42 text/plain 404 0") { ok("ludic build links http.ll for a program that uses Http.*") }
+      else { bad2("http.ludic via ludic build", `got [{got2}]`) }
+    } else { bad2("ludic build of an Http.* program", capture_line(`tail -1 {tmp_dir()}/http_lb.out`)) }
   }
 
   feat_case("events/recurse", "", "16", "recurse.ludic (EV6: re-entrant emit is depth-bounded, no runaway cycle)")