ILFIVE is a library of Lisp objects in C, with an Ada-95 binding. It is not currently undergoing much further development these days but is used in other projects such as Clarrhmos and Electrocardiognosis.
Licence is LGPL.
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Feb. 6, 2004 (JD2453042) added niliada, a library of native Lisp objects in Ada, using controlled finalization features of the Ada language to implement a `behind the scenes' incremental garbage colector.
Licence is GPL.
Enjoy,
Alexandru