diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index c417db1..afd8760 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -11,12 +11,12 @@ before_script:
 
 sandbox:
   script:
+    - hugo --quiet
     - node tools/pdf.js
     - hugo -F
     - node tools/minify.js
     - firebase use default
     - firebase deploy --token "$FIREBASE_SANDBOX_TOKEN"
-    - ls public/schedule/
   artifacts:
     paths:
       - public
@@ -27,6 +27,7 @@ prod:
   variables:
     HUGO_ENV: production
   script:
+    - hugo --quiet
     - node tools/pdf.js
     - hugo --baseURL https://2019.devfesttoulouse.fr/
     - node tools/minify.js
diff --git a/themes/devfest-theme-hugo b/themes/devfest-theme-hugo
index defa281..6a8d7c8 160000
--- a/themes/devfest-theme-hugo
+++ b/themes/devfest-theme-hugo
@@ -1 +1 @@
-Subproject commit defa281b712030049b17f57741fba6ebc2984e83
+Subproject commit 6a8d7c8af563c5fa71e36e31fe6425ce85702f36
diff --git a/tools/minify.js b/tools/minify.js
index 7201299..3268bfe 100644
--- a/tools/minify.js
+++ b/tools/minify.js
@@ -1,20 +1,27 @@
 const {readFileSync, writeFileSync} = require('fs');
 const {sync: glob} = require('glob');
 const {minify} = require('html-minifier');
-const {Logger} = require('plop-logger');
+const {Logger, LogLevel} = require('plop-logger');
 const {colorEmojiConfig} = require('plop-logger/lib/extra/colorEmojiConfig');
 
 Logger.config = colorEmojiConfig;
 const logger = Logger.getLogger('minifier');
+logger.level = LogLevel.All;
 
-glob(`public/**/*.html`)
-    .forEach(file => {
-        const html = readFileSync(file, 'utf8');
-        const minified = minify(html, {});
-        const gain = html.length - minified.length;
-        if (gain > 0) {
-            const percent = (gain / html.length) * 100;
-            logger.info(file, () => ['gain', percent.toFixed(2), '%'].join(" "));
-            writeFileSync(file, minified, {flag: 'w'});
-        }
-    });
+const htmlFiles = `public/**/*.html`;
+logger.info('Compress HTML files', htmlFiles);
+
+const totalGain = glob(htmlFiles)
+  .map(file => {
+    const html = readFileSync(file, 'utf8');
+    const minified = minify(html, {});
+    const gain = html.length - minified.length;
+    if (gain > 0) {
+      const percent = (gain / html.length) * 100;
+      logger.debug(file, () => ['gain', percent.toFixed(2), '%'].join(" "));
+      writeFileSync(file, minified, {flag: 'w'});
+    }
+    return gain;
+  }).reduce((acc, elt) => acc + elt, 0);
+
+logger.info('Total gain', '' + totalGain);