FWIW, this is likely why–

perl -MJSON -MJSON::Tiny -le 'print encode_json([JSON::Tiny::true()])'
encountered object 'JSON::Tiny::_Bool=SCALAR(0x9401c88)', but neither 
+allow_blessed, convert_blessed nor allow_tags settings are enabled (o
+r TO_JSON/FREEZE method missing) at -e line 1.
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