diff --git a/UPGRADING.md b/UPGRADING.md
index 30d7ed8..6cfa6dc 100644
--- a/UPGRADING.md
+++ b/UPGRADING.md
@@ -1,3 +1,20 @@
+# (2022-06-11) RevBank 3.4
+
+RevBank now has built-in hidden accounts and balanced transactions. These
+accounts will be made automatically, and hidden from the user interface. Apart
+from that, they function as normal accounts (for now).
+
+If you have scripts that parse `.revbank.log` or `revbank.products`, you may
+want to ignore all accounts that start with `-` or `+`.
+
+In the hopefully very unlikely event that you have existing user accounts that
+start with `-` or `+`, those will have to be renamed manually, as such accounts
+are no longer accessible.
+
+For your custom plugins, you may want to add `->add_contra` calls to every
+`$cart->add` call that does not already have them. Unbalanced transactions will
+probably be deprecated in a future version.
+
 # (2022-06-04) RevBank 3.3
 
 Raw amounts without a command are no longer supported. There was already an
diff --git a/lib/RevBank/Cart.pm b/lib/RevBank/Cart.pm
index 2ff8d9e..e22bcd8 100644
--- a/lib/RevBank/Cart.pm
+++ b/lib/RevBank/Cart.pm
@@ -66,11 +66,7 @@ sub checkout($self, $user) {
         return;
     }
 
-    if ($user =~ /^[-+]/) {
-        # Hidden internal accounts
-        my $canonical = RevBank::Users::parse_user($user);
-        $user = $canonical // RevBank::Users::create($user);
-    }
+    $user = RevBank::Users::assert_user($user);
 
     my $entries = $self->{entries};
 
diff --git a/lib/RevBank/Cart/Entry.pm b/lib/RevBank/Cart/Entry.pm
index c4c808a..e927e13 100644
--- a/lib/RevBank/Cart/Entry.pm
+++ b/lib/RevBank/Cart/Entry.pm
@@ -27,6 +27,7 @@ sub new($class, $amount, $description, $attributes = {}) {
 
 sub add_contra($self, $user, $amount, $description) {
     $amount = RevBank::Amount->parse_string($amount) if not ref $amount;
+    $user = RevBank::Users::assert_user($user);
 
     $description =~ s/\$you/$self->{user}/g if defined $self->{user};
 
@@ -84,7 +85,7 @@ sub as_printable($self) {
     push @s, sprintf "%8s %s", $self->{amount}->string_flipped, $self->{description};
 
     for my $c ($self->contras) {
-        next if RevBank::Users::is_hidden($c->{user});
+        next if RevBank::Users::is_hidden($c->{user}) and not $ENV{REVBANK_DEBUG};
 
         push @s, sprintf(
             "%11s %s %s",
diff --git a/lib/RevBank/Messages.pm b/lib/RevBank/Messages.pm
index af39c49..b716932 100644
--- a/lib/RevBank/Messages.pm
+++ b/lib/RevBank/Messages.pm
@@ -55,7 +55,7 @@ sub hook_reject($class, $plugin, $reason, $abort, @) {
 }
 
 sub hook_user_balance($class, $username, $old, $delta, $new, @) {
-    return if hidden $username;
+    return if hidden $username and not $ENV{REVBANK_DEBUG};
 
     my $sign = $delta->cents >= 0 ? '+' : '-';
     my $rood = $new->cents < 0 ? '31;' : '';
@@ -67,7 +67,7 @@ sub hook_user_balance($class, $username, $old, $delta, $new, @) {
 }
 
 sub hook_user_created($class, $username, @) {
-    return if hidden $username;
+    return if hidden $username and not $ENV{REVBANK_DEBUG};
 
     say "New account '$username' created.";
 }
diff --git a/lib/RevBank/Users.pm b/lib/RevBank/Users.pm
index 35fe23b..e08ab2b 100644
--- a/lib/RevBank/Users.pm
+++ b/lib/RevBank/Users.pm
@@ -7,6 +7,7 @@ no warnings qw(experimental::signatures);
 
 use RevBank::Global;
 use RevBank::Plugins;
+use Carp ();
 
 my $filename = "revbank.accounts";
 
@@ -77,16 +78,30 @@ sub update($username, $delta, $transaction_id) {
     );
 }
 
-sub parse_user($username) {
-    my $users = _read();
-    return undef if not exists $users->{ lc $username };
-    return $users->{ lc $username }->[0];
-}
-
 sub is_hidden($username) {
     return $username =~ /^[-+]/;
 }
 
+sub parse_user($username) {
+    return undef if is_hidden($username);
+
+    my $users = _read();
+    return exists $users->{ lc $username }
+        ? $users->{ lc $username }->[0]
+        : undef;
+}
+
+sub assert_user($username) {
+    my $users = _read();
+
+    return exists $users->{ lc $username }
+        ? $users->{ lc $username }->[0]
+        : (is_hidden($username)
+            ? create($username)
+            : Carp::croak("Account '$username' does not exist")
+        );
+}
+
 1;
 
 
diff --git a/plugins/deposit b/plugins/deposit
index 6ac93cd..0de950d 100644
--- a/plugins/deposit
+++ b/plugins/deposit
@@ -19,7 +19,10 @@ sub amount :Tab(13.37,42) ($self, $cart, $amount, @) {
     return $message . "How are we receiving this $amount?", \&how
         if keys %{ $self->{deposit_methods} };
 
-    $cart->add(+$self->{amount}, "Deposit", { is_deposit => 1 });
+    $cart
+        ->add(+$self->{amount}, "Deposit", { is_deposit => 1 })
+        ->add_contra("-deposits/other", -$self->{amount}, "Deposited by \$you");
+
     return ACCEPT;
 }
 
@@ -35,7 +38,15 @@ sub how :Tab(&how_tab) ($self, $cart, $input, @) {
         return shift @{ $how->{prompts} }, \&how_prompt;
     }
 
-    $cart->add(+$self->{amount}, $how->{description}, { is_deposit => 1, method => $how->{_key} });
+    my $contra = 
+          $how->{_key} eq 'cash'      ? '-cash'
+        : $how->{_key} eq 'reimburse' ? '-expenses/reimbursed'
+        :                               "-deposits/$how->{_key}";
+
+    $cart
+        ->add(+$self->{amount}, $how->{description}, { is_deposit => 1, method => $how->{_key} })
+        ->add_contra($contra, -$self->{amount}, "$how->{description} by \$you");
+
     return ACCEPT;
 }
 
@@ -53,7 +64,11 @@ sub how_prompt($self, $cart, $input, @) {
     }
 
     my $desc = sprintf $how->{description}, @{ $how->{answers} };
+    my $contra = $how->{_key} eq 'cash' ? '-cash' : "-deposits/$how->{_key}";
+
+    $cart
+        ->add(+$self->{amount}, $desc, { is_deposit => 1, method => $how->{_key} })
+        ->add_contra($contra, -$self->{amount}, "$desc by \$you");
 
-    $cart->add(+$self->{amount}, $desc, { is_deposit => 1, method => $how->{_key} });
     return ACCEPT;
 }
diff --git a/plugins/pfand b/plugins/pfand
index e08dce9..57eafe1 100644
--- a/plugins/pfand
+++ b/plugins/pfand
@@ -27,7 +27,9 @@ sub product :Tab(&tab) ($self, $cart, $product, @) {
         or return REJECT, "Invalid pfand amount for $product";
 
     if ($pfand) {
-        $cart->add(+$pfand, "Pfand zurueck", { is_return => 1 });
+        $cart
+            ->add(+$pfand, "Pfand zurueck", { is_return => 1 })
+            ->add_contra("-pfand", -$pfand, "Pfand fuer \$you");
     } else {
         say "$product: Kein Pfand";
     }
@@ -44,7 +46,9 @@ sub hook_add_entry ($class, $cart, $entry, @) {
 
     my $pfand = _read_pfand->{ $entry->attribute('product_id') } or return;
 
-    $cart->add(-$pfand, "Pfand", { is_pfand => 1 });
+    $cart
+        ->add(-$pfand, "Pfand", { is_pfand => 1 })
+        ->add_contra("-pfand", +$pfand, "Pfand von \$you");
 
     return;
 }
diff --git a/plugins/products b/plugins/products
index 297a692..32c86fa 100644
--- a/plugins/products
+++ b/plugins/products
@@ -42,11 +42,17 @@ sub command :Tab(edit,&tab) ($self, $cart, $command, @) {
         return ACCEPT;
     }
 
-    $cart->add(
-        -$price,
-        $product->{description},
-        { product_id => $product->{id}, plugin => $self->id }
-    );
+    $cart
+        ->add(
+            -$price,
+            $product->{description},
+            { product_id => $product->{id}, plugin => $self->id }
+        )
+        ->add_contra(
+            "+sales/products",
+            +$price,
+            "\$you bought $product->{description}"
+        );
     return ACCEPT;
 }
 
diff --git a/plugins/revspace_barcode b/plugins/revspace_barcode
index 231dfb1..be2b981 100644
--- a/plugins/revspace_barcode
+++ b/plugins/revspace_barcode
@@ -14,11 +14,19 @@ sub command :Tab(barcode) ($self, $cart, $command, @) {
 }
 
 sub data($self, $cart, $input, @) {
-    $cart->add(
-        -0.07,
-        "Barcode <$input>",
-        { is_barcode => 1, barcode_data => $input }
-    );
+    my $price = 0.07;
+
+    $cart
+        ->add(
+            -$price,
+            "Barcode <$input>",
+            { is_barcode => 1, barcode_data => $input }
+        )
+        ->add_contra(
+            "+sales/barcodes",
+            +$price,
+            "\$you bought barcode <$input>"
+        );
 
     return ACCEPT;
 }
diff --git a/plugins/revspace_bounties b/plugins/revspace_bounties
index d0c7b24..483eafb 100644
--- a/plugins/revspace_bounties
+++ b/plugins/revspace_bounties
@@ -9,7 +9,9 @@ my %bounties = (
 
 sub command :Tab(BOUNTY1,BOUNTY2,BOUNTY3,BOUNTY4) ($self, $cart, $command, @) {
     if ($command =~ /BOUNTY(\d+)/) {
-        $cart->add(+$bounties{$1}[0], $bounties{$1}[1]);
+        $cart
+            ->add(+$bounties{$1}[0], $bounties{$1}[1])
+            ->add_contra("-expenses/bounties", -$bounties{$1}[0], "$command by \$you");
         return ACCEPT;
     }
 
diff --git a/plugins/revspace_mollie b/plugins/revspace_mollie
index e07d7cb..460261a 100644
--- a/plugins/revspace_mollie
+++ b/plugins/revspace_mollie
@@ -35,11 +35,17 @@ sub command($self, $cart, $command, @) {
         $description .= " TEST MODE ($result->{test_amount})";
     }
 
-    $cart->add(
-        +$amount,
-        $description,
-        { is_deposit => 1, method => 'online', mollie_id => $id, no_repeat => 1 }
-    );
+    $cart
+        ->add(
+            +$amount,
+            $description,
+            { is_deposit => 1, method => 'online', mollie_id => $id, no_repeat => 1 }
+        )
+        ->add_contra(
+            "-deposits/online",
+            -$amount,
+            "$description by \$you"
+        );
     return ACCEPT;
 }
 
diff --git a/plugins/unlisted b/plugins/unlisted
index ca5437d..02709bf 100644
--- a/plugins/unlisted
+++ b/plugins/unlisted
@@ -13,7 +13,10 @@ sub amount($self, $cart, $arg, @) {
     $self->{amount} = parse_amount($arg) or return REJECT, "Invalid amount.";
 
     if ($self->{command} eq 'donate') {
-        $cart->add(-$self->{amount}, "Donation (THANK YOU!)");
+        $cart
+            ->add(-$self->{amount}, "Donation (THANK YOU!)")
+            ->add_contra("+donations", +$self->{amount}, "Donation by \$you");
+
         return ACCEPT;
     }
 
@@ -21,7 +24,10 @@ sub amount($self, $cart, $arg, @) {
 }
 
 sub description($self, $cart, $desc, @) {
-    $cart->add(-$self->{amount}, "Unlisted: $desc");
+    $cart
+        ->add(-$self->{amount}, "Unlisted: $desc")
+        ->add_contra("+sales/unlisted", +$self->{amount}, "Unlisted: $desc by \$you");
+
     return ACCEPT;
 }
 
diff --git a/plugins/users b/plugins/users
index f1155c1..9f21357 100644
--- a/plugins/users
+++ b/plugins/users
@@ -28,12 +28,12 @@ sub hook_checkout($class, $cart, $user, $transaction_id, @) {
 }
 
 sub list($self) {
-    system "sort -f revbank.accounts | grep -v ^# | perl -pe's/( -[\\d.]+)/\\e[31;1m\$1\\e[0m/' | more";
+    system "sort -f revbank.accounts | grep -v ^# | perl -ne's/( -[\\d.]+)/\\e[31;1m\$1\\e[0m/; print if not /^[-+]/' | more";
     return ACCEPT;
 }
 
 sub shame($self) {
-    system "sort -k2 -n revbank.accounts | grep -v ^# | grep -- ' -' | perl -pe's/( -[\\d.]+)/\\e[31;1m\$1\\e[0m/' | more";
+    system "sort -k2 -n revbank.accounts | grep -v ^# | grep -- ' -' | perl -ne's/( -[\\d.]+)/\\e[31;1m\$1\\e[0m/; print if not /^[-+]/' | more";
     return ACCEPT;
 }
 
diff --git a/revbank b/revbank
index 241eff9..2bb8744 100755
--- a/revbank
+++ b/revbank
@@ -18,7 +18,7 @@ use RevBank::Global;
 use RevBank::Messages;
 use RevBank::Cart;
 
-our $VERSION = "3.3";
+our $VERSION = "3.4";
 our %HELP1 = (
     "abort" => "Abort the current transaction",
 );