diff --git a/knowledge base/safeline.md b/knowledge base/safeline.md
new file mode 100644
index 0000000..e9354c2
--- /dev/null
+++ b/knowledge base/safeline.md	
@@ -0,0 +1,60 @@
+# SafeLine
+
+Self-hosted Web Application Firewall.
+
+1. [TL;DR](#tldr)
+1. [Further readings](#further-readings)
+   1. [Sources](#sources)
+
+## TL;DR
+
+<!-- Uncomment if used
+<details>
+  <summary>Setup</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]
+- [Main repository]
+
+### Sources
+
+<!--
+  Reference
+  ═╬═Time══
+  -->
+
+<!-- In-article sections -->
+<!-- Knowledge base -->
+<!-- Files -->
+<!-- Upstream -->
+[main repository]: https://github.com/chaitin/SafeLine
+[website]: https://waf.chaitin.com/
+
+<!-- Others -->
diff --git a/knowledge base/self-hosting.md b/knowledge base/self-hosting.md
index dc3859d..354f167 100644
--- a/knowledge base/self-hosting.md	
+++ b/knowledge base/self-hosting.md	
@@ -24,6 +24,7 @@ The _art_ of hosting and managing applications on one's own servers instead of c
 | [Paperless-ngx]  | Document management system          |                                           |
 | [PhotoPrism]     | Photo and video management solution | Google Photo, [Immich]                    |
 | [Rundeck]        | Task runner                         | [AWX], [CTFreak], [Semaphore], [Zuul]     |
+| [SafeLine]       | Web Application Firewall            |                                           |
 | [Semaphore]      | Task runner                         | [AWX], [CTFreak], [Rundeck], [Zuul]       |
 | [Uptime Kuma]    | Status page                         | [Gatus], [Statping-ng], [Vigil]           |
 | [Wallabag]       | Web page saver                      | Pocket                                    |
@@ -52,6 +53,7 @@ The _art_ of hosting and managing applications on one's own servers instead of c
 [paperless-ngx]: paperless-ngx.md
 [photoprism]: photoprism.md
 [rundeck]: rundeck.md
+[safeline]: safeline.md
 [uptime kuma]: uptime%20kuma.md
 [wallabag]: wallabag.md