diff --git a/lib/plugins.js b/lib/plugins.js
index 5cd2e2ee..0486fbc2 100644
--- a/lib/plugins.js
+++ b/lib/plugins.js
@@ -438,7 +438,7 @@ exports.cashOut = function cashOut(deviceFingerprint, tx, cb) {
   });
 };
 
-exports.depositAck = function depositAck(deviceFingerprint, tx) {
+exports.dispenseAck = function dispenseAck(deviceFingerprint, tx) {
   _setDispenseStatus(deviceFingerprint, tx, 'dispensedDeposit');
 };
 
diff --git a/lib/postgresql_interface.js b/lib/postgresql_interface.js
index f9867060..dbd2d0c5 100644
--- a/lib/postgresql_interface.js
+++ b/lib/postgresql_interface.js
@@ -75,7 +75,7 @@ exports.recordBill = function recordBill(deviceFingerprint, rec, cb) {
     fields.push('uuid');
   }
 
-  client.query(getInsertQuery('bills', fields), values, function(err, billInfo) {
+  client.query(getInsertQuery('bills', fields), values, function(err) {
     if (err && PG_ERRORS[err.code] === 'uniqueViolation')
       return cb(null, {code: 204});
 
@@ -244,3 +244,19 @@ exports.changeTxStatus = function changeTxStatus(txId, newStatus, data, cb) {
   }
   client.query(query, values, cb);
 };
+
+exports.decrementCartridges =
+    function decrementCartridges(fingerprint, cartridge1, cartridge2, cb) {
+  var query = 'UPDATE devices SET cartridge_1_bills = cartridge_1_bills - $1, ' +
+    'cartridge_2_bills = cartridge_2_bills - $2 ' +
+    'WHERE fingerprint = $3';
+  client.query(query, [cartridge1, cartridge2, fingerprint], cb);
+};
+
+exports.fillCartridges =
+    function fillCartridges(fingerprint, cartridge1, cartridge2, cb) {
+  var query = 'UPDATE devices SET cartridge_1_bills = $1, ' +
+    'cartridge_2_bills = $2 ' +
+    'WHERE fingerprint = $3';
+  client.query(query, [cartridge1, cartridge2, fingerprint], cb);
+};
diff --git a/lib/routes.js b/lib/routes.js
index dc2d6c18..6af33da5 100644
--- a/lib/routes.js
+++ b/lib/routes.js
@@ -114,8 +114,8 @@ function cashOut(req, res) {
   });
 }
 
-function depositAck(req, res) {
-  plugins.depositAck(getFingerprint(req), req.body);
+function dispenseAck(req, res) {
+  plugins.dispenseAck(getFingerprint(req), req.body);
   res.json(200);
 }
 
@@ -180,7 +180,7 @@ function init(localConfig) {
   app.post('/send', authMiddleware, send);
 
   app.post('/cash_out', authMiddleware, cashOut);
-  app.post('/deposit_ack', authMiddleware, depositAck);
+  app.post('/dispense_ack', authMiddleware, dispenseAck);
 
   app.post('/event', authMiddleware, deviceEvent);
   app.post('/verify_user', authMiddleware, verifyUser);