diff --git a/roles/nginx/files/nginx.conf b/roles/nginx/files/nginx.conf
index 2e3b93d..11c0df3 100644
--- a/roles/nginx/files/nginx.conf
+++ b/roles/nginx/files/nginx.conf
@@ -57,7 +57,12 @@ http {
     # Avoids the issue where a non-gzip capable client (which is extremely rare
     # today) would display gibberish if their proxy gave them the gzipped version.
     gzip_vary on;
+
+    # Compression level (1-9).
+    # 5 is a perfect compromise between size and CPU usage, offering about
+    # 75% reduction for most ASCII files (almost identical to level 9).
     gzip_comp_level 5;
+
     gzip_min_length 860;
     gzip_disable "msie6";
     gzip_http_version 1.1;