doc: Add staging workflow diagram

1 files changed, 19 insertions, 0 deletions

diff --git a/doc/contributing/submitting-changes.chapter.md b/doc/contributing/submitting-changes.chapter.md
index 984169f0954bd..40fc5ea789213 100644
--- a/doc/contributing/submitting-changes.chapter.md
+++ b/doc/contributing/submitting-changes.chapter.md
@@ -159,6 +159,25 @@ The last checkbox is fits [CONTRIBUTING.md](https://github.com/NixOS/nixpkgs/blo
 - Hydra builds for master and staging should not be used as testing platform, it’s a build farm for changes that have been already tested.
 - When changing the bootloader installation process, extra care must be taken. Grub installations cannot be rolled back, hence changes may break people’s installations forever. For any non-trivial change to the bootloader please file a PR asking for review, especially from \@edolstra.
 
+```{.graphviz caption="Staging workflow"}
+digraph {
+    "small changes" [shape=none]
+    "mass-rebuilds and other large changes" [shape=none]
+    "critical security fixes" [shape=none]
+    "broken staging-next fixes" [shape=none]
+
+    "small changes" -> master
+    "mass-rebuilds and other large changes" -> staging
+    "critical security fixes" -> master
+    "broken staging-next fixes" -> "staging-next"
+
+    "staging-next" -> master [color="#E85EB0"] [label="stabilization ends"] [fontcolor="#E85EB0"]
+    "staging" -> "staging-next" [color="#E85EB0"] [label="stabilization starts"] [fontcolor="#E85EB0"]
+
+    master -> "staging-next" -> staging [color="#5F5EE8"] [label="every six hours/any time"] [fontcolor="#5F5EE8"]
+}
+```
+
 ### Master branch {#submitting-changes-master-branch}
 
 The `master` branch is the main development branch. It should only see non-breaking commits that do not cause mass rebuilds.