diff --git a/knowledge base/supervisor.md b/knowledge base/supervisor.md
new file mode 100644
index 0000000..4ecbbad
--- /dev/null
+++ b/knowledge base/supervisor.md	
@@ -0,0 +1,58 @@
+# Supervisor
+
+TODO
+
+Client/server system allowing users to control processes on UNIX-like operating systems.
+
+1. [TL;DR](#tldr)
+1. [Further readings](#further-readings)
+
+## TL;DR
+
+<!-- Uncomment if used
+<details>
+  <summary>Installation and configuration</summary>
+
+```sh
+```
+
+</details>
+-->
+
+<!-- Uncomment if used
+<details>
+  <summary>Usage</summary>
+
+```sh
+```
+
+</details>
+-->
+
+<!-- Uncomment if used
+<details>
+  <summary>Real world use cases</summary>
+
+```sh
+```
+
+</details>
+-->
+
+## Further readings
+
+- [Website]
+- [Github]
+- [Systemd]
+
+<!--
+  Reference
+  ═╬═Time══
+  -->
+
+<!-- Knowledge base -->
+[systemd]: systemd.md
+
+<!-- Upstream -->
+[github]: https://github.com/Supervisor/supervisor
+[website]: http://supervisord.org/
diff --git a/knowledge base/systemd.md b/knowledge base/systemd.md
index f73cf5f..5609126 100644
--- a/knowledge base/systemd.md	
+++ b/knowledge base/systemd.md	
@@ -1,7 +1,5 @@
 # Systemd
 
-## Table of contents <!-- omit in toc -->
-
 1. [TL;DR](#tldr)
 1. [User services](#user-services)
    1. [Failed to connect to bus: No medium found](#failed-to-connect-to-bus-no-medium-found)
@@ -10,7 +8,8 @@
    1. [Disable systemd-resolved](#disable-systemd-resolved)
    1. [Ignore the DNS servers list given by the DHCP server](#ignore-the-dns-servers-list-given-by-the-dhcp-server)
    1. [Manually set DNS servers](#manually-set-dns-servers)
-1. [Sources](#sources)
+1. [Further readings](#further-readings)
+   1. [Sources](#sources)
 
 ## TL;DR
 
@@ -295,7 +294,11 @@ FallbackDNS=1.1.1.1 1.0.0.1 2606:4700:4700::1111 2606:4700:4700::1001 # Cloudfla
 
 Restart the `systemd-resolved` service to apply the new settings.
 
-## Sources
+## Further readings
+
+- [Supervisor]
+
+### Sources
 
 - [How to disable systemd-resolved in Ubuntu]
 - [What are the systemctl options to list all failed units?]
@@ -306,9 +309,13 @@ Restart the `systemd-resolved` service to apply the new settings.
 - [Changing DNS with systemd-resolved]
 
 <!--
-  References
+  Reference
+  ═╬═Time══
   -->
 
+<!-- Knowledge base -->
+[supervisor]: supervisor.md
+
 <!-- Others -->
 [changing dns with systemd-resolved]: https://notes.enovision.net/linux/changing-dns-with-resolve
 [how to disable systemd-resolved in ubuntu]: https://askubuntu.com/questions/907246/how-to-disable-systemd-resolved-in-ubuntu