/usr/share/guile/2.0/system/ is in guile-2.0-libs 2.0.9+1-1ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/guile/2.0/system/base/
/usr/share/guile/2.0/system/base/ck.scm
/usr/share/guile/2.0/system/base/compile.scm
/usr/share/guile/2.0/system/base/lalr.scm
/usr/share/guile/2.0/system/base/lalr.upstream.scm
/usr/share/guile/2.0/system/base/language.scm
/usr/share/guile/2.0/system/base/message.scm
/usr/share/guile/2.0/system/base/pmatch.scm
/usr/share/guile/2.0/system/base/syntax.scm
/usr/share/guile/2.0/system/base/target.scm
/usr/share/guile/2.0/system/foreign.scm
/usr/share/guile/2.0/system/repl/
/usr/share/guile/2.0/system/repl/command.scm
/usr/share/guile/2.0/system/repl/common.scm
/usr/share/guile/2.0/system/repl/debug.scm
/usr/share/guile/2.0/system/repl/describe.scm
/usr/share/guile/2.0/system/repl/error-handling.scm
/usr/share/guile/2.0/system/repl/repl.scm
/usr/share/guile/2.0/system/repl/server.scm
/usr/share/guile/2.0/system/vm/
/usr/share/guile/2.0/system/vm/coverage.scm
/usr/share/guile/2.0/system/vm/frame.scm
/usr/share/guile/2.0/system/vm/inspect.scm
/usr/share/guile/2.0/system/vm/instruction.scm
/usr/share/guile/2.0/system/vm/objcode.scm
/usr/share/guile/2.0/system/vm/program.scm
/usr/share/guile/2.0/system/vm/trace.scm
/usr/share/guile/2.0/system/vm/trap-state.scm
/usr/share/guile/2.0/system/vm/traps.scm
/usr/share/guile/2.0/system/vm/vm.scm
/usr/share/guile/2.0/system/xref.scm