diff --git a/Dockerfile.debian b/Dockerfile.debian
index e81fbf144..1de777787 100644
--- a/Dockerfile.debian
+++ b/Dockerfile.debian
@@ -33,6 +33,7 @@ COPY crates/robot-kit/Cargo.toml crates/robot-kit/Cargo.toml
 # Create dummy targets declared in Cargo.toml so manifest parsing succeeds.
 RUN mkdir -p src benches crates/robot-kit/src \
     && echo "fn main() {}" > src/main.rs \
+    && echo "" > src/lib.rs \
     && echo "fn main() {}" > benches/agent_benchmarks.rs \
     && echo "pub fn placeholder() {}" > crates/robot-kit/src/lib.rs
 RUN --mount=type=cache,id=zeroclaw-cargo-registry,target=/usr/local/cargo/registry,sharing=locked \