This is the output I get when I set geiser-log-verbose-p and geiser-log-verbose-debug-p in emacs:
INFO: REQUEST: <20>: (geiser:eval '#f '(manage 'new-environment 'combinators))
INFO: RETORT: ((error (key . retort-syntax)) (output . "
;Loading \"sdf/common/overrides.scm\"... done
;Loading \"sdf/common/utils.scm\"... done
;Loading \"sdf/common/indexes.scm\"... done
;Loading \"sdf/common/collections.scm\"... done
;Loading \"sdf/common/memoizers.scm\"... done
;Loading \"sdf/common/predicates.scm\"... done
;Loading \"sdf/common/predicate-metadata.scm\"... done
;Loading \"sdf/common/applicability.scm\"... done
;Loading \"sdf/common/generic-procedures.scm\"... done
;Loading \"sdf/common/pretty-printer.scm\"... done
;Loading \"sdf/common/operators.scm\"... done
;Loading \"sdf/common/operations.scm\"... done
;Loading \"sdf/common/package.scm\"... done
;Loading \"sdf/common/predicate-counter.scm\"... done
;Loading \"sdf/common/simple-tests.scm\"... done
;Loading \"sdf/common/trie.scm\"... done
;Loading \"sdf/combinators/function-combinators.scm\"... done
;Value: (combinators)
1 (user) => "))
INFO: <20>: processed
It looks like it confuses the loading messages for errors? I wonder how it works for >>19, I have the latest Geiser from MELPA so it shouldn't be an issue? (Although I don't have the geiser-mit package installed, do I need that?)