diff --git a/index.html b/index.html
index 7929b3b..13fa34f 100644
--- a/index.html
+++ b/index.html
@@ -123,6 +123,15 @@ body { margin: 0; font: 13px/1.4 system-ui, sans-serif; background: #f5f5f5; col
 }
 #worldMapBtn:hover { background: #3a5278; }
 
+#repoLink {
+  margin-left: auto;
+  font-size: 12px;
+  color: #7eb8f7;
+  text-decoration: none;
+  white-space: nowrap;
+}
+#repoLink:hover { color: #9ecef8; text-decoration: underline; }
+
 /* worldwide map overlay */
 #worldOverlay {
   display: none; position: fixed; inset: 0; z-index: 3000;
@@ -158,6 +167,7 @@ body { margin: 0; font: 13px/1.4 system-ui, sans-serif; background: #f5f5f5; col
   <label>Year <select id="yearSel"></select></label>
   <span id="sitesCount" style="font-size:12px;color:#aaa;white-space:nowrap"></span>
   <button type="button" id="worldMapBtn" title="World map of all sites">World map</button>
+  <a id="repoLink" href="https://git.delattre.de/pantierra/efast-phenocam-validation" target="_blank" rel="noopener noreferrer">Source code</a>
 </div>
 
 <div id="worldOverlay" aria-hidden="true">