diff --git a/tbot/tc/selftest/tc/build.py b/tbot/tc/selftest/tc/build.py
index 11419e25..c90992cf 100644
--- a/tbot/tc/selftest/tc/build.py
+++ b/tbot/tc/selftest/tc/build.py
@@ -30,7 +30,7 @@ def toolchains(self) -> typing.Dict[str, linux.build.Toolchain]:
         """Return toolchains available on this host."""
         return {
             "selftest-toolchain": linux.build.EnvScriptToolchain(
-                self.workdir / ".selftest-toolchain.sh"
+                self.workdir / ".selftest-toolchain.sh"  # type: ignore
             )
         }