diff --git a/ci/lint.sh b/ci/lint.sh
index baba040..5dd2451 100755
--- a/ci/lint.sh
+++ b/ci/lint.sh
@@ -5,7 +5,7 @@ IFS=$'\n\t'
 # Ensure packages lists are sorted
 for file in packages; do
     cat "${file}.txt" | sort > "/tmp/sorted-${file}.txt"
-    if ! diff "/tmp/sorted-${file}.txt" "${file}.txt" >/dev/null 2>&1; then
+    if ! diff -u "/tmp/sorted-${file}.txt" "${file}.txt"; then
         echo "Lint error: ${file}.txt is not sorted"
         exit 1
     fi
diff --git a/packages.txt b/packages.txt
index 8022d6a..c69853e 100644
--- a/packages.txt
+++ b/packages.txt
@@ -23,6 +23,7 @@ docker.io
 dselect
 emacsen-common
 enchant
+gfortran
 git
 gnupg
 golang
@@ -466,6 +467,7 @@ libkrb5-3
 libkrb5support0
 libksba8
 liblapack3
+liblapack-dev
 liblcms2-2
 liblcms2-dev
 libldap-2.4-2