From ff1d6b08292826ca4a62b148fac264ca0bb846fe Mon Sep 17 00:00:00 2001
From: Christine Elisabeth Koppel <kuutruu@posteo.net>
Date: Thu, 12 Feb 2026 22:05:17 +0100
Subject: [PATCH] Add Maple Mono Nerd Font and custom theme support to Forgejo

---
 .../modules/styling/forgejo/home.tmpl         | 13 +++++++
 .../modules/styling/forgejo/theme-custom.css  | 18 +++++++++
 nix-system-configs/modules/system/forgejo.nix | 39 +++++++++++++++++++
 3 files changed, 70 insertions(+)
 create mode 100644 nix-system-configs/modules/styling/forgejo/home.tmpl
 create mode 100644 nix-system-configs/modules/styling/forgejo/theme-custom.css

diff --git a/nix-system-configs/modules/styling/forgejo/home.tmpl b/nix-system-configs/modules/styling/forgejo/home.tmpl
new file mode 100644
index 0000000..0a4b2fc
--- /dev/null
+++ b/nix-system-configs/modules/styling/forgejo/home.tmpl
@@ -0,0 +1,13 @@
+[[:Template:Template "base/head" .]]
+<div role="main" aria-label="[[:Template:If .IsSigned]][[:Template:Ctx.Locale.Tr "dashboard"]][[:Template:Else]][[:Template:Ctx.Locale.Tr "home"]][[:Template:End]]" class="page-content home">
+	<div class="tw-mb-8 tw-px-8">
+		<div class="center">
+			<div class="hero">
+				<h1 class="ui icon header title">
+					Forgejo hosted on NixOS!
+				</h1>
+			</div>
+		</div>
+	</div>
+</div>
+[[:Template:Template "base/footer" .]]
\ No newline at end of file
diff --git a/nix-system-configs/modules/styling/forgejo/theme-custom.css b/nix-system-configs/modules/styling/forgejo/theme-custom.css
new file mode 100644
index 0000000..4ad9f83
--- /dev/null
+++ b/nix-system-configs/modules/styling/forgejo/theme-custom.css
@@ -0,0 +1,18 @@
+@font-face {
+  font-family: 'Maple Mono NF';
+  src: url('/assets/fonts/MapleMonoNerd.ttf') format('truetype');
+  font-weight: normal;
+  font-style: normal;
+  font-display: swap;
+}
+
+/* import base Forgejo theme so we only override what we need */
+@import "./theme-forgejo-auto.css";
+
+:root {
+  /* prefer the Maple Mono Nerd Font for monospace usage */
+  --fonts-monospace: 'Maple Mono NF', var(--fonts-monospace);
+  /* if you want the UI proportional font to also use Maple, set --fonts-override */
+  /* --fonts-override: 'Maple Mono NF', var(--fonts-override); */
+}
+
diff --git a/nix-system-configs/modules/system/forgejo.nix b/nix-system-configs/modules/system/forgejo.nix
index 4da5e8b..c660db5 100644
--- a/nix-system-configs/modules/system/forgejo.nix
+++ b/nix-system-configs/modules/system/forgejo.nix
@@ -8,6 +8,23 @@
   cfg = config.services.forgejo;
   srv = cfg.settings.server;
   choose = paths: builtins.head (builtins.filter (p: builtins.pathExists p) paths);
+  mapleZip = pkgs.fetchurl {
+    url = "https://github.com/subframe7536/maple-font/releases/download/v7.9/MapleMonoNormal-NF-unhinted.zip";
+    sha256 = "1j8bh8fzrnrj4348xj8l1jpbchbblhi2a7gryarf2mi88xr1yc3f";
+  };
+
+  # Add a runCommand that unpacks the downloaded zip and exposes a stable ttf path
+  mapleFonts = pkgs.runCommand "maple-fonts" {buildInputs = [pkgs.unzip];} ''
+    mkdir -p $out/tmp
+    unzip -q ${mapleZip} -d $out/tmp
+    f="$(find $out/tmp -type f -name '*.ttf' | head -n1)"
+    if [ -z "$f" ]; then
+      echo "no ttf found" >&2
+      exit 1
+    fi
+    mkdir -p $out/fonts
+    cp "$f" $out/fonts/MapleMonoNerd.ttf
+  '';
 in {
   options.local = {
     hostname = lib.mkOption {
@@ -100,8 +117,30 @@ in {
         #   ENABLED = false;
         # };
       };
+
+      settings.ui = {
+        DEFAULT_THEME = "custom";
+        THEMES = "forgejo-auto,forgejo-light,forgejo-dark,custom";
+      };
     };
 
+    systemd.tmpfiles.rules = [
+      "d '${config.services.forgejo.customDir}/templates' - forgejo forgejo - -"
+      "d '${config.services.forgejo.customDir}/public' - forgejo forgejo - -"
+      "d '${config.services.forgejo.customDir}/public/assets' - forgejo forgejo - -"
+      "d '${config.services.forgejo.customDir}/public/assets/css' - forgejo forgejo - -"
+      # ensure fonts directory exists
+      "d '${config.services.forgejo.customDir}/public/assets/fonts' - forgejo forgejo - -"
+      # install the TTF from the Nix store into the Forgejo customDir
+      "C+ '${config.services.forgejo.customDir}/public/assets/fonts/MapleMonoNerd.ttf' - forgejo forgejo - ${mapleFonts}/fonts/MapleMonoNerd.ttf"
+      "C+ '${config.services.forgejo.customDir}/public/assets/css/theme-custom.css' - forgejo forgejo - ${
+        ../styling/forgejo/theme-custom.css
+      }"
+      "C+ '${config.services.forgejo.customDir}/templates/home.tmpl' - forgejo forgejo - ${
+        ../styling/forgejo/home.tmpl
+      }"
+    ];
+
     # Open ports in the firewall.
     networking.firewall.allowedTCPPorts = [3000];