diff --git a/src/niar/build.py b/src/niar/build.py
index 14c4f93..9f0fe6c 100644
--- a/src/niar/build.py
+++ b/src/niar/build.py
@@ -75,8 +75,11 @@ def main(np: Project, args):
             products = plan.execute_local(f"build/{subdir}")
 
         # The outf doesn't exist here; it's only used for the digest name basis.
+
+        # This is specific to toolchains that use Yosys, but I'm unlikely to use anything else ...
+        deps = [f"{np.name}.il", f"{np.name}.ys"]
         cr.add_process(execute_build,
-            infs=[{np.path.build(subdir, fn): plan.files[fn]}],
+            infs=[{np.path.build(subdir, fn): plan.files[fn] for fn in deps}],
             outf=np.path.build(subdir, np.name))
 
         cr.run()