diff --git a/bash-fast-replace/README.md b/bash-fast-replace/README.md
index 59bef80..0bfc8d5 100644
--- a/bash-fast-replace/README.md
+++ b/bash-fast-replace/README.md
@@ -6,14 +6,14 @@ An implementation in bash.
 
 To create the corpus.csv and pairs.csv files. And perform the replacements:
 
-```bash
+```shell
 make install # create corpus and pairs
 make run # create file with the replaced values
 ```
 
 Then to test:
 
-```bash
+```shell
 make test # Checks that the replacement worked
 ```
 
@@ -23,7 +23,7 @@ make test # Checks that the replacement worked
 `shuf` is amazing. Using /dev/urandom directly produces broken pipe errors on when using Make.
 
 Speed is not great... But no surprize there.
-````bash
+````shell
 $ make install
 ./bin/pairs.sh
 Generating csv/pairs.csv...