Source code of the assembler/desassembler DAMS is available since March 2015
-Pascal SEGUY is the author of the DAMS utility (assembler and desassembler), edited by Micro Applications in 1985 and by Audiogenic Software LTD in the U.K.
I just discovered in a CPCWiki thread about FutureOS that Mr. SEGUY did put the source code of DAMS on Github.