diff --git a/core/lib/Foswiki/Engine.pm b/core/lib/Foswiki/Engine.pm
index 34e5c35b66..3ba4dcd5a8 100644
--- a/core/lib/Foswiki/Engine.pm
+++ b/core/lib/Foswiki/Engine.pm
@@ -85,8 +85,7 @@ has connectionData =>
 
 Parameter attributes are arrays of hashrefs with keys =-name= and =-value= where
 the former is a plain string and the latter may be either a scalar or an
-arrayref. In addition to those two =bodyParamaters= element hashref may contain
-additional key =-upload= which value is boolean. 
+arrayref.
 
 =cut
 
@@ -423,7 +422,7 @@ sub _preparePath { }
 sub _prepareBodyParameters { return []; }
 
 # Abstract initializer for uploads
-sub _prepareUploads { return {}; }
+sub _prepareUploads { return []; }
 
 =begin TML
 
diff --git a/core/lib/Foswiki/Engine/PSGI.pm b/core/lib/Foswiki/Engine/PSGI.pm
index 7189cf1266..13538fd396 100644
--- a/core/lib/Foswiki/Engine/PSGI.pm
+++ b/core/lib/Foswiki/Engine/PSGI.pm
@@ -147,11 +147,6 @@ around _prepareBodyParameters => sub {
         my $param = {
             -name  => $upname,
             -value => \@values,
-
-            # SMELL uploads are handled by dedicated psgi->uploads
-            # Note that we record the encoded name of the upload. It will be
-            # decoded in prepareUploads, which rewrites the {uploads} hash.
-            -upload => ( scalar( $psgi->upload($pname) ) ? 1 : 0 ),
         };
         push @params, $param;
     }
@@ -197,6 +192,7 @@ around _prepareUploads => sub {
             filename    => $upload->filename,
             basename    => $upload->basename,
             tmpname     => $upload->path,
+            headers     => $upload->headers,
             contentType => $upload->content_type,
             size        => $upload->size,
           };
diff --git a/core/lib/Foswiki/Exception.pm b/core/lib/Foswiki/Exception.pm
index df58eb802b..e43fbad546 100644
--- a/core/lib/Foswiki/Exception.pm
+++ b/core/lib/Foswiki/Exception.pm
@@ -384,11 +384,11 @@ sub errorStr {
     return $str;
 }
 
-package Foswiki::Exception::ASSERT;
+package Foswiki::Exception::Harmless;
 use Moo;
 extends qw(Foswiki::Exception);
 
-# This class is only for distinguishing ASSERT-generated exceptions.
+# For informational exceptions.
 
 package Foswiki::Exception::Fatal;
 use Moo;
@@ -396,9 +396,67 @@ extends qw(Foswiki::Exception);
 
 # To cover perl/system errors.
 
+package Foswiki::Exception::ASSERT;
+use Moo;
+extends qw(Foswiki::Exception::Fatal);
+
+# This class is only for distinguishing ASSERT-generated exceptions.
+
+=begin TML
+
+---++ Exception Foswiki::Exception::CB
+
+Root of callback support exception tree.
+
+=cut
+
+package Foswiki::Exception::CB;
+use Moo;
+extends qw(Foswiki::Exception);
+
+=begin TML
+
+---+ Exception Foswiki::Exception::CB::Last
+
+Must be raised by a callback code to signal it wants to be the last on the
+execution chain.
+
+=cut
+
+package Foswiki::Exception::CB::Last;
+use Moo;
+extends qw(Foswiki::Exception::CB);
+
+=begin TML
+
+---++ ObjectAttribute returnValue
+
+The value to be returned by =Foswiki::Aux::Callbacks::callback()= method.
+
+=cut
+
+has returnValue => (
+    is        => 'ro',
+    predicate => 1,
+);
+
+=begin TML
+
+---+ Exception Foswiki::Exception::Cfg::InvalidKeyName
+
+If configuration key doesn't pass validation.
+
+=cut
+
+package Foswiki::Exception::Cfg::InvalidKeyName;
+use Moo;
+extends qw(Foswiki::Exception::Fatal);
+
+has keyName => ( is => 'rw', required => 1, );
+
 =begin TML
 
----++ Exception Foswiki::Exception::HTTPResponse
+---+ Exception Foswiki::Exception::HTTPResponse
 
 Used to send HTTP status responses to the user.
 
@@ -526,44 +584,6 @@ around BUILDARGS => sub {
     return $orig->( $class, %params );
 };
 
-=begin TML
-
----++ Exception Foswiki::Exception::CB
-
-Root of callback support exception tree.
-
-=cut
-
-package Foswiki::Exception::CB;
-use Moo;
-extends qw(Foswiki::Exception);
-
-=begin TML
-
----++ Exception Foswiki::Exception::CB::Last
-
-Must be raised by a callback code to signal it wants to be the last on the
-execution chain.
-
-=cut
-
-package Foswiki::Exception::CB::Last;
-use Moo;
-extends qw(Foswiki::Exception::CB);
-
-=begin TML
-
----++ ObjectAttribute returnValue
-
-The value to be returned by =Foswiki::Aux::Callbacks::callback()= method.
-
-=cut
-
-has returnValue => (
-    is        => 'ro',
-    predicate => 1,
-);
-
 1;
 __END__
 Foswiki - The Free and Open Source Wiki, http://foswiki.org/
diff --git a/core/lib/Foswiki/Request.pm b/core/lib/Foswiki/Request.pm
index ce59f16176..79bdd42523 100644
--- a/core/lib/Foswiki/Request.pm
+++ b/core/lib/Foswiki/Request.pm
@@ -19,7 +19,7 @@ Fields:
    * =remote_user= Remote HTTP authenticated user
    * =secure= Boolean value about use of encryption
    * =server_port= Port that the webserver listens on
-   * =uploads= arrayref of Foswiki::Request::Upload objects
+   * =uploads= hashref of Foswiki::Request::Upload objects
    * =uri= the request uri
 
 The following fields are parsed from the =pathInfo=
@@ -155,7 +155,7 @@ has _param => ( is => 'rw', lazy => 1, default => sub { {} }, );
 
 =begin TML
 
----++ ObjectAttribute uploads( [ \%uploads ] ) -> $hashref
+---++ ObjectAttribute uploads -> $hashref
 
 Gets/Sets request uploads field. Keys are uploaded file names,
 as sent by browser, and values are Foswiki::Request::Upload objects.
@@ -166,18 +166,9 @@ has uploads => (
     is      => 'rw',
     lazy    => 1,
     builder => '_establishUploads',
-    isa     => Foswiki::Object::isaARRAY( 'uploads', noUndef => 1 ),
+    isa     => Foswiki::Object::isaHASH( 'uploads', noUndef => 1 ),
 );
 
-# upload_list attribute keeps list of request uploads. Used to initialize
-# uploads attribute with corresponding =Foswiki::Request::Upload= instances.
-# SMELL Isn't it needed for engine code only?
-has upload_list => (
-    is      => 'rw',
-    lazy    => 1,
-    default => sub { [] },
-    isa     => Foswiki::Object::isaARRAY( 'upload_list', noUndef => 1, ),
-);
 has param_list => (
     is        => 'rw',
     predicate => 1,
@@ -685,6 +676,10 @@ sub delete {
     my $this = shift;
     foreach my $p (@_) {
         next unless exists $this->_param->{$p};
+        my $pval = $this->param($p);
+        if ( exists $this->uploads->{$pval} ) {
+            CORE::delete $this->uploads->{$pval};
+        }
         CORE::delete $this->_param->{$p};
     }
     my %deleted_key = map { $_ => 1 } @_;
@@ -1268,10 +1263,6 @@ sub _establishParamList {
 
     # Process body parameters individually to take care of uploads.
     foreach my $param ( @{ $engine->bodyParameters } ) {
-        if ( $param->{-upload} ) {
-            push @{ $this->upload_list }, $param->{-name};
-            delete $param->{-upload};
-        }
         push @params, $param;
     }
     $this->param($_) foreach @params;
@@ -1298,12 +1289,12 @@ sub _establishMethod {
 sub _establishUploads {
     my $this       = shift;
     my $rawUploads = $this->app->engine->uploads;
-    my @reqUploads;
+    my %reqUploads;
     foreach my $upload (@$rawUploads) {
-        push @reqUploads,
-          $this->create( 'Foswiki::Request::Upload', %$upload, );
+        $reqUploads{ $upload->{filename} } =
+          $this->create( 'Foswiki::Request::Upload', %$upload );
     }
-    return \@reqUploads;
+    return \%reqUploads;
 }
 
 =begin TML
diff --git a/core/lib/Foswiki/Request/Upload.pm b/core/lib/Foswiki/Request/Upload.pm
index 7ed3fb8031..c0376b66e7 100644
--- a/core/lib/Foswiki/Request/Upload.pm
+++ b/core/lib/Foswiki/Request/Upload.pm
@@ -19,6 +19,7 @@ use Moo;
 use namespace::clean;
 extends qw(Foswiki::Object);
 
+has headers     => ( is => 'ro', );
 has filename    => ( is => 'ro', );
 has size        => ( is => 'ro', );
 has contentType => ( is => 'ro', );
diff --git a/core/lib/Foswiki/UI/Upload.pm b/core/lib/Foswiki/UI/Upload.pm
index 284f869384..35d0b4a6b8 100644
--- a/core/lib/Foswiki/UI/Upload.pm
+++ b/core/lib/Foswiki/UI/Upload.pm
@@ -114,7 +114,7 @@ sub _upload {
     my $this = shift;
 
     my @msgs;
-    foreach my $upload ( @{ $this->app->request->uploads } ) {
+    foreach my $upload ( values %{ $this->app->request->uploads } ) {
         push @msgs, $this->_upload_file($upload);
     }