TPA-RFC-73: Add initial dependency graph (team#41721)

policy/tpa-rfc-73-tails-infra-merge-roadmap.md

@@ -111,6 +111,137 @@ Summary: Tails infra merge roadmap.
  [Whisperback]: https://tails.net/contribute/working_together/roles/sysadmins/services/#index20h1
  [puppet-rbac]: https://gitlab.tails.boum.org/tails/puppet-rbac
 
+### Dependency graph
+
+```mermaid
+flowchart TD
+    classDef retire fill:#f99,stroke:#f00,color:black;
+    classDef keep fill:#9f9,stroke:#090,color:black;
+    classDef merge fill:#adf,stroke:#00f,color:black;
+
+    subgraph ColorCode [Color code]
+      style ColorCode fill:#fff,stroke:#fff;
+      Keep
+      class Keep keep
+      Merge
+      class Merge merge
+      Retire
+      class Retire retire
+      NeedDiscussion[Need discussion]
+    end
+
+    subgraph Independent [Independent from Puppet]
+      Documentation ~~~
+      PasswordStore[Password Store] ~~~
+      Schleuder ~~~
+      AptRepository[APT repository] ~~~
+      Colocations
+      LimeSurvey ~~~
+      Mailman[Mailman lists] ~~~
+      MTA ~~~
+      Registrars ~~~
+      SysadminsGitLab[Sysadmins GitLab] ~~~
+      SecurityPolicy[Security Policy]
+      Bitcoin ~~~
+      Calendar ~~~
+      MeetingReminder ~~~
+      XMPP -->
+      XmppBot[XMPP bot]
+    end
+
+    subgraph Puppet [Puppet repo and server]
+    direction TB
+        Tor7[Upgrade Tor's Puppet Server to Puppet 7] --> PuppetModules & EYAML & CommitSigning
+        PuppetModules[Puppet modules] --> HybridPuppet
+        EYAML --> HybridPuppet
+        CommitSigning[Commit signing] --> HybridPuppet
+        HybridPuppet[Hybrid Puppet codebase]
+    end
+
+    subgraph Basic [Basic system functionality]
+        DNS
+        Backups --> Monitoring
+        TLS --> Monitoring
+        Firewall ~~~
+        Authentication
+    end
+
+    subgraph ToKeep [Keep]
+        direction TB;
+        HedgeDoc ~~~
+        IsoHistory[ISO history] ~~~
+        IpSpace[IP space] ~~~
+        TbArchive[Tor Browser archive] ~~~
+        BitTorrent ~~~
+        WhisperBack ~~~
+        AptSnapshots[APT snapshots]
+    end
+
+    subgraph Services
+        WebServer[Web servers] ~~~
+        Weblate ~~~
+        TorBridge[Tor Bridge] ~~~
+        Website
+        TailsTeamGitLab[Tails Team GitLab] ~~~
+        MirrorPool[Mirror pool] ~~~
+        git-annex -->
+        Gitolite
+        Jenkins -->
+        VPN
+    end
+
+    ColorCode ~~~ Puppet
+    ColorCode ~~~~ Independent
+
+    Puppet --> ToKeep;
+    Puppet --> Basic
+
+    Basic --> Services
+
+    Services --> PuppetCodebase[Consolidated Puppet codebase]
+    Services --> Virtualization
+
+    class DNS retire
+    class Firewall retire
+    class Backups retire
+    class Monitoring retire
+    class DNS retire
+    class TLS retire
+    class Bitcoin retire
+    class Calendar retire
+    class MeetingReminder retire
+    class Virtualization retire
+    class VPN retire
+    class XMPP retire
+    class XmppBot retire
+    class Jenkins retire
+
+    class Tor7 keep
+    class HedgeDoc keep
+    class IsoHistory keep
+    class IpSpace keep
+    class TbArchive keep
+    class BitTorrent keep
+    class WhisperBack keep
+    class AptSnapshots keep
+
+    class Documentation merge
+    class PasswordStore merge
+    class Schleuder merge
+    class AptRepository merge
+    class Colocations merge
+    class LimeSurvey merge
+    class Mailman merge
+    class MTA merge
+    class Registrars merge
+    class SysadminsGitLab merge
+    class SecurityPolicy merge
+    class PuppetModules merge
+    class WebServer merge
+    class PuppetCodebase merge
+    class HybridPuppet merge
+```
+
 # References
 
 See the [TPA/Tails sysadmins overview][] document that was used to inform the