diff --git a/base/lnls-prune-artifacts.sh b/base/lnls-prune-artifacts.sh
index 4ce99dd..4a4408e 100755
--- a/base/lnls-prune-artifacts.sh
+++ b/base/lnls-prune-artifacts.sh
@@ -77,6 +77,34 @@ get_used_epics_modules() {
     filter_out_paths "$all_modules" "$unused_modules"
 }
 
+# Traverse ancestor directories of each provided path, and concatenate all
+# their .lnls-keep-paths defined entries as absolute paths.
+get_defined_paths_to_keep() {
+    for path; do
+        if [ "${path:0:1}" != "/" ]; then
+            >&2 echo "error: get_defined_paths_to_keep() expects absolute paths, but got '$path'"
+            exit 1
+        fi
+
+        while true; do
+            keep_path_file="$path/.lnls-keep-paths"
+
+            if [ -f "$keep_path_file" ]; then
+                keep_paths=$(cat "$keep_path_file")
+
+                for keep_path in $keep_paths; do
+                    # output it as an absolute path
+                    realpath "$path"/$keep_path
+                done
+            fi
+
+            [ "$path" == "/" ] && break
+
+            path=$(dirname $path)
+        done
+    done | sort -u
+}
+
 prune_module_dirs() {
     module=$1
 
@@ -84,6 +112,7 @@ prune_module_dirs() {
     keep_paths=$(cat << EOF
 $(find_shared_libraries $module)
 $(find $module -type f -regex ".*\.\(cmd\|db\|template\|req\|substitutions\)" -printf "%h\n" | sort -u)
+$(get_defined_paths_to_keep $module)
 EOF
     )
 
@@ -154,11 +183,16 @@ remove_unused_shared_libraries() {
         remove_libs=$(echo "$remove_libs" | grep -vx $lib)
     done
 
+    keep_paths=$(get_defined_paths_to_keep $remove_libs)
+
     for lib in $remove_libs; do
-        size=$(du -hs $lib | cut -f 1)
+        # if library is not found inside any $keep_dirs, remove it
+        if find $keep_paths -path "$lib" -exec false {} +; then
+            size=$(du -hs $lib | cut -f 1)
 
-        echo "Removing shared library '$lib' ($size)"
-        rm -f ${lib%.so*}.so*
+            echo "Removing shared library '$lib' ($size)"
+            rm -f ${lib%.so*}.so*
+        fi
     done
 }