commit 957d704139d6430fcce7e5b0d7058572f220ab09
Author: Jonas Meeuws <jonas.meeuws@gmail.com>
Date:   Thu Mar 12 01:27:34 2026 +0100

    std.datetime.timezone: Support the TZDIR environment variable on POSIX.

diff --git a/std/datetime/timezone.d b/std/datetime/timezone.d
index 6a1898b0e..4e7b1f95b 100644
--- a/std/datetime/timezone.d
+++ b/std/datetime/timezone.d
@@ -2033,7 +2033,15 @@ public:
     }
     else version (Posix)
     {
-        enum defaultTZDatabaseDir = "/usr/share/zoneinfo/";
+        static nothrow
+        string defaultTZDatabaseDir()
+        {
+            import std.exception : assumeWontThrow;
+            import std.process : environment;
+            return environment
+                .get("TZDIR", "/usr/share/zoneinfo/")
+                .assumeWontThrow; // nothrow on POSIX
+        }
     }
     else version (Windows)
     {
@@ -2455,11 +2463,13 @@ public:
             // RefCounted variable, but here, no references to the payload is
             // escaped to the outside, so this should be @trusted
             () @trusted {
-                foreach (DirEntry de; dirEntries(tzDatabaseDir, SpanMode.depth))
+                foreach (DirEntry de; dirEntries(tzDatabaseDir, SpanMode.depth, false))
                 {
                     if (de.isFile)
                     {
                         auto tzName = de.name[tzDatabaseDir.length .. $];
+                        if (tzName.startsWith("/"))
+                            tzName = tzName[1 .. $];
 
                         if (!tzName.extension().empty ||
                             !tzName.startsWith(subName) ||