diff --git a/b3sum/README.md b/b3sum/README.md
index d1fbc2135..a55c5a60c 100644
--- a/b3sum/README.md
+++ b/b3sum/README.md
@@ -69,3 +69,7 @@ On Linux for example, Cargo will put the compiled binary in
 If you want to install directly from this directory, you can run `cargo
 install --path .`. Or you can just build with `cargo build --release`,
 which puts the binary at `./target/release/b3sum`.
+
+Also, shell completions and a man page are generated at build time. The
+directory where these are output can be found by running `find ./target
+-path '*/b3sum-*/out' -type d`.