diff --git a/nextnumber b/nextnumber
index f70ec50..8e87f8f 100755
--- a/nextnumber
+++ b/nextnumber
@@ -1,16 +1,14 @@
 #!/usr/bin/env bash
 # TODO: Find a less trashy way to get the next available error code
-if ! shopt -s globstar; then
+if ! shopt -s globstar
+then
   echo "Error: This script depends on Bash 4." >&2
   exit 1
 fi
 
-for i in 1 2; do
-  last=$(grep --no-filename --invert-match "^prop" ./**/*.hs \
-	| grep --extended-regexp --word-regexp --only-matching "$i[0-9]{3}" \
-	| sort --numeric-sort \
-	| tail --lines 1
-)
+for i in 1 2
+do
+  last=$(grep -hv "^prop" ./**/*.hs | grep -Ewo "$i[0-9]{3}" | sort -n | tail -n 1)
   echo "Next ${i}xxx: $((last+1))"
 done
 
diff --git a/quicktest b/quicktest
index 0654189..4eab80b 100755
--- a/quicktest
+++ b/quicktest
@@ -16,7 +16,7 @@ if [[ $var == *$'\nTrue'* ]]
 then
   exit 0
 else
-  grep --context 3 --regexp "Fail" --regexp "Tracing" <<< "${var}"
+  grep -C 3 -e "Fail" -e "Tracing" <<< "${var}"
   exit 1
 fi
 ) 2>&1