diff --git a/src/bin/consciousness.rs b/src/bin/consciousness.rs
index 2fcfebf..61d28e1 100644
--- a/src/bin/consciousness.rs
+++ b/src/bin/consciousness.rs
@@ -2,6 +2,17 @@
 #![warn(unreachable_pub)]
 
 fn main() {
+    // Force the default panic hook to print a backtrace. stderr is
+    // already redirected to a daemon log; without this the hook obeys
+    // RUST_BACKTRACE (unset by default), so the log only shows the
+    // "note: run with `RUST_BACKTRACE=full`" tail and the actual
+    // frames are lost.
+    //
+    // SAFETY: called before any other thread is spawned, so no
+    // concurrent env reader can race.
+    if std::env::var_os("RUST_BACKTRACE").is_none() {
+        unsafe { std::env::set_var("RUST_BACKTRACE", "1"); }
+    }
     std::panic::set_backtrace_style(std::panic::BacktraceStyle::Short);
     consciousness::user::main()
 }