container fixes

README.md

@@ -9,6 +9,8 @@ Clone zig and prune binary files from history:
 ```
 $ git clone https://github.com/ziglang/zig zig2
 $ cd zig2
+$ git config user.name "$(git config --get user.name)"
+$ git config user.email "$(git config --get user.email)"
 $ git filter-repo --prune-empty=never --prune-degenerate never --invert-paths --path-glob 'stage1/zig1.wasm*' --path stage1/zig1.c
 ```
 
@@ -16,7 +18,7 @@ Now build an isolated container with a bunch of zig historic dependencies:
 
 ```
 $ docker build -t zig-repro .
-$ docker run -ti --rm \
+$ docker run -ti --rm --name zig-repro \
     -v ~/code:/x \
     -v /home/$USER/.cache/zig:/home/$USER/.cache/zig \
     -w /x/zig2 \