+- Implement & test read-sequence, write-sequence for (un)signed-8 vectors
+
+- Eliminate consing in sc-read-chars-ef
+
+- Make reader work with simple-streams
+
+- external format handling: load aliases, load formats, etc.
+
+- Handle writing beyond the end of a mapped-simple-stream properly
+
+- handle device-file-position for mapped streams