Got most of the new memory architecture roughed out.

src/c/payloads/time.h

@@ -0,0 +1,29 @@
+/**
+ *  payloads/cons.h
+ *
+ *  A cons cell.
+ *
+ *  (c) 2026 Simon Brooke <simon@journeyman.cc>
+ *  Licensed under GPL version 2.0, or, at your option, any later version.
+ */
+
+#ifndef __psse_payloads_cons_h
+#define __psse_payloads_cons_h
+
+#include "memory/pointer.h"
+
+/**
+ * @brief Tag for a time stamp.
+ */
+#define TIMETAG     "TIME"
+
+/**
+ * The payload of a time cell: an unsigned 128 bit value representing micro-
+ * seconds since the estimated date of the Big Bang (actually, for
+ * convenience, 14Bn years before 1st Jan 1970 (the UNIX epoch))
+ */
+struct time_payload {
+    unsigned __int128 value;
+};
+
+#endif