diff --git a/doc/development/design/index.mdwn b/doc/development/design/index.mdwn
index c9e8a6d..e6f713e 100644
--- a/doc/development/design/index.mdwn
+++ b/doc/development/design/index.mdwn
@@ -312,12 +312,12 @@
     * Service dependencies
         + Scenario 1: Tests need X11
             + X11 can be run under various servers
-                + If DISPLAY is set, have option
-                    + Use current DISPLAY
+                + If `DISPLAY` is set, have option
+                    + Use current `DISPLAY`
                     + Use Xvfb
                     + Use Xephyr (may need a WM to run inside)
-                + If DISPLAY is not set (headless environment)
-                    + Set DISPLAY
+                + If `DISPLAY` is not set (headless environment)
+                    + Set `DISPLAY`
                     + Use Xvfb (requires `pkg:deb/debian/xvfb`)
         + Scenario 2: Tests need PostgreSQL
             + Alternative 1: Use existing PostgreSQL on system.