open $ctx->{lh}, '+>>', "$ctx->{-tmp}/solve.log" or die "open: $!";
my $solver = PublicInbox::SolverGit->new($ctx->{ibx},
\&solve_result, $ctx);
+ $solver->{gits} //= [ $ctx->{git} ];
$solver->{tmp} = $ctx->{-tmp}; # share tmpdir
# PSGI server will call this immediately and give us a callback (-wcb)
sub {