From 7d9bb7d1836f8e72f8976880f9d14d66bf877907 Mon Sep 17 00:00:00 2001
From: Erik Simon <mail@erik-s.dev>
Date: Fri, 18 Sep 2026 21:36:41 +0200
Subject: [PATCH] fix(common): expose /etc/timezone so flatpak apps stop
 defaulting to UTC

Flatpak detects the sandbox timezone from /etc/timezone, not the
/etc/localtime symlink NixOS creates by default. Without it every
flatpak app (Telegram included) silently falls back to UTC, showing
message timestamps 2h off from local time.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UJqEmY1y3AYX3JoX4Y6b21
---
 common.nix | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/common.nix b/common.nix
index c148422..35c5c48 100644
--- a/common.nix
+++ b/common.nix
@@ -1,4 +1,4 @@
-{ pkgs, ... }:
+{ pkgs, config, ... }:
 
 # Shared base for all hosts: user, SSH hardening, nix settings, packages.
 {
@@ -99,6 +99,8 @@
 
   # ---- Locale / firewall base ----
   time.timeZone = "Europe/Berlin";
+  # Flatpak needs /etc/timezone, falls back to UTC if not set.
+  environment.etc."timezone".text = config.time.timeZone;
   i18n.defaultLocale = "en_US.UTF-8";
   console.keyMap = "de";