diff --git a/lib/app.js b/lib/app.js
index fc1c77ba..700be241 100644
--- a/lib/app.js
+++ b/lib/app.js
@@ -32,7 +32,7 @@ function runOnce () {
   const app = express()
   const localApp = express()
 
-  return settingsLoader.load()
+  return settingsLoader.loadLatest()
   .then(settings => {
     poller.start(settings)
 
diff --git a/lib/exchange.js b/lib/exchange.js
index d396d863..2908e6ec 100644
--- a/lib/exchange.js
+++ b/lib/exchange.js
@@ -1,5 +1,4 @@
 const configManager = require('./config-manager')
-const settingsLoader = require('./settings-loader')
 
 function noExchangeError (cryptoCode) {
   const err = new Error('No exchange plugin defined for: ' + cryptoCode)
@@ -8,15 +7,13 @@ function noExchangeError (cryptoCode) {
   return err
 }
 
-function lookupExchange (cryptoCode) {
-  const settings = settingsLoader.settings()
+function lookupExchange (settings, cryptoCode) {
   return configManager.cryptoScoped(cryptoCode, settings.config).exchange
 }
 
-function fetchExchange (cryptoCode) {
+function fetchExchange (settings, cryptoCode) {
   return Promise.resolve()
   .then(() => {
-    const settings = settingsLoader.settings()
     const plugin = lookupExchange(cryptoCode)
     if (!plugin) throw noExchangeError(cryptoCode)
     const account = settings.accounts[plugin]
@@ -26,18 +23,18 @@ function fetchExchange (cryptoCode) {
   })
 }
 
-function buy (cryptoAtoms, fiatCode, cryptoCode) {
-  return fetchExchange(cryptoCode)
+function buy (settings, cryptoAtoms, fiatCode, cryptoCode) {
+  return fetchExchange(settings, cryptoCode)
   .then(r => r.exchange.buy(r.account, cryptoAtoms, fiatCode, cryptoCode))
 }
 
-function sell (cryptoAtoms, fiatCode, cryptoCode) {
-  return fetchExchange(cryptoCode)
+function sell (settings, cryptoAtoms, fiatCode, cryptoCode) {
+  return fetchExchange(settings, cryptoCode)
   .then(r => r.exchange.sell(r.account, cryptoAtoms, fiatCode, cryptoCode))
 }
 
-function active (fiatCode, cryptoCode) {
-  return !!lookupExchange(cryptoCode)
+function active (settings, fiatCode, cryptoCode) {
+  return !!lookupExchange(settings, cryptoCode)
 }
 
 module.exports = {
diff --git a/lib/plugins.js b/lib/plugins.js
index a557413b..4ec6fb39 100644
--- a/lib/plugins.js
+++ b/lib/plugins.js
@@ -87,6 +87,15 @@ function plugins (settings) {
     }
   }
 
+  function fetchCurrentConfigVersion () {
+    const sql = `select id from config_users
+    where type=$1
+    order by id desc
+    limit 1`
+
+    return db.one(sql, ['config'])
+  }
+
   function pollQueries (deviceTime, deviceId, deviceRec) {
     const config = configManager.machineScoped(deviceId, settings.config)
     const fiatCode = config.fiatCurrency
@@ -95,22 +104,29 @@ function plugins (settings) {
       config.bottomCashOutDenomination ]
     const virtualCartridges = [config.virtualCashOutDenomination]
 
-    const tickerPromises = cryptoCodes.map(c => ticker.getRates(fiatCode, c))
-    const balancePromises = cryptoCodes.map(wallet.balance)
+    const tickerPromises = cryptoCodes.map(c => ticker.getRates(settings, fiatCode, c))
+    const balancePromises = cryptoCodes.map(c => wallet.balance(settings, c))
     const pingPromise = recordPing(deviceId, deviceTime, deviceRec)
+    const currentConfigVersionPromise = fetchCurrentConfigVersion()
 
-    const promises = [dbm.cartridgeCounts(deviceId), pingPromise].concat(tickerPromises, balancePromises)
+    const promises = [
+      dbm.cartridgeCounts(deviceId),
+      pingPromise,
+      currentConfigVersionPromise
+    ].concat(tickerPromises, balancePromises)
 
     return Promise.all(promises)
     .then(arr => {
       const cartridgeCounts = arr[0]
-      const tickers = arr.slice(2, cryptoCodes.length + 2)
-      const balances = arr.slice(cryptoCodes.length + 2)
+      const currentConfigVersion = arr[2]
+      const tickers = arr.slice(3, cryptoCodes.length + 3)
+      const balances = arr.slice(cryptoCodes.length + 3)
 
       return {
         cartridges: buildCartridges(cartridges, virtualCartridges, cartridgeCounts),
         rates: buildRates(deviceId, tickers),
-        balances: buildBalances(deviceId, balances)
+        balances: buildBalances(deviceId, balances),
+        currentConfigVersion
       }
     })
   }
@@ -119,7 +135,7 @@ function plugins (settings) {
   // a dbm unique dbm record in the table already.
   function executeTx (deviceId, tx) {
     return dbm.addOutgoingTx(deviceId, tx)
-    .then(() => wallet.sendCoins(tx.toAddress, tx.cryptoAtoms, tx.cryptoCode))
+    .then(() => wallet.sendCoins(settings, tx.toAddress, tx.cryptoAtoms, tx.cryptoCode))
     .then(txHash => {
       const fee = null // Need to fill this out in plugins
       const toSend = {cryptoAtoms: tx.cryptoAtoms, fiat: tx.fiat}
@@ -144,7 +160,7 @@ function plugins (settings) {
     .then(() => {
       const market = [fiatCode, cryptoCode].join('')
 
-      if (!exchange.active(cryptoCode)) return
+      if (!exchange.active(settings, cryptoCode)) return
 
       logger.debug('[%s] Pushing trade: %d', market, cryptoAtoms)
       if (!tradesQueues[market]) tradesQueues[market] = []
@@ -187,7 +203,7 @@ function plugins (settings) {
         serialNumber
       }
 
-      return wallet.newAddress(cryptoCode, info)
+      return wallet.newAddress(settings, cryptoCode, info)
       .then(address => {
         const newTx = R.assoc('toAddress', address, tx)
 
@@ -208,7 +224,10 @@ function plugins (settings) {
   function fiatBalance (fiatCode, cryptoCode, deviceId) {
     const config = configManager.scoped(cryptoCode, deviceId, settings.config)
 
-    return Promise.all([ticker.getRates(fiatCode, cryptoCode), wallet.balance(cryptoCode)])
+    return Promise.all([
+      ticker.getRates(settings, fiatCode, cryptoCode),
+      wallet.balance(settings, cryptoCode)
+    ])
     .then(([rates, balanceRec]) => {
       const rawRate = rates.rates.ask
       const commission = (new BigNumber(config.cashInCommission).div(100)).plus(1)
@@ -231,7 +250,7 @@ function plugins (settings) {
   }
 
   function processTxStatus (tx) {
-    return wallet.getStatus(tx.toAddress, tx.cryptoAtoms, tx.cryptoCode)
+    return wallet.getStatus(settings, tx.toAddress, tx.cryptoAtoms, tx.cryptoCode)
     .then(res => dbm.updateTxStatus(tx, res.status))
   }
 
@@ -355,7 +374,7 @@ function plugins (settings) {
   }
 
   function executeTradesForMarket (settings, fiatCode, cryptoCode) {
-    if (!exchange.active(cryptoCode)) return
+    if (!exchange.active(settings, cryptoCode)) return
 
     const market = [fiatCode, cryptoCode].join('')
     logger.debug('[%s] checking for trades', market)
@@ -370,7 +389,7 @@ function plugins (settings) {
 
     logger.debug('[%s] making a trade: %d', market, tradeEntry.cryptoAtoms.toString())
 
-    return exchange.buy(tradeEntry.cryptoAtoms, tradeEntry.fiatCode, tradeEntry.cryptoCode)
+    return exchange.buy(settings, tradeEntry.cryptoAtoms, tradeEntry.fiatCode, tradeEntry.cryptoCode)
     .then(() => logger.debug('[%s] Successful trade.', market))
     .catch(err => {
       tradesQueues[market].push(tradeEntry)
@@ -444,7 +463,7 @@ function plugins (settings) {
   function sweepHD (row) {
     const cryptoCode = row.crypto_code
 
-    return wallet.sweep(row.hd_serial)
+    return wallet.sweep(settings, row.hd_serial)
     .then(txHash => {
       if (txHash) {
         logger.debug('[%s] Swept address with tx: %s', cryptoCode, txHash)
diff --git a/lib/route-helpers.js b/lib/route-helpers.js
index b6855917..f15c7951 100644
--- a/lib/route-helpers.js
+++ b/lib/route-helpers.js
@@ -1,5 +1,6 @@
 const R = require('ramda')
 
+const db = require('./db')
 const dbm = require('./postgresql_interface')
 const T = require('./time')
 const TRANSACTION_EXPIRATION = 2 * T.days
@@ -32,4 +33,8 @@ function fetchPhoneTx (phone) {
   })
 }
 
-module.exports = {stateChange, fetchPhoneTx}
+function updateDeviceConfigVersion (versionId) {
+  return db.none('update devices set user_config_id=$1', [versionId])
+}
+
+module.exports = {stateChange, fetchPhoneTx, updateDeviceConfigVersion}
diff --git a/lib/routes.js b/lib/routes.js
index 3852323b..f1838947 100644
--- a/lib/routes.js
+++ b/lib/routes.js
@@ -62,7 +62,8 @@ function poll (req, res, next) {
       reboot,
       rates: results.rates,
       balances: results.balances,
-      coins: config.cryptoCurrencies
+      coins: config.cryptoCurrencies,
+      configVersion: results.currentConfigVersion
     }
 
     if (response.idVerificationEnabled) {
@@ -421,13 +422,14 @@ function populateDeviceId (req, res, next) {
 }
 
 function populateSettings (req, res, next) {
-  const versionId = req.headers['config-version-id']
+  const versionId = req.headers['config-version']
   if (!versionId) {
-    logger.debug('No config-version-id header')
+    logger.debug('No config-version header')
     return res.sendStatus(400)
   }
 
   settingsLoader.log(versionId)
   .then(settings => { req.settings = settings })
+  .then(() => helpers.updateDeviceConfigVersion(versionId))
   .catch(next)
 }
diff --git a/lib/settings-loader.js b/lib/settings-loader.js
index ca17efd4..5355226b 100644
--- a/lib/settings-loader.js
+++ b/lib/settings-loader.js
@@ -5,6 +5,8 @@ const db = require('./db')
 let settingsCache
 
 function load (versionId) {
+  if (!versionId) throw new Error('versionId is required')
+
   return Promise.all([loadConfig(versionId), loadAccounts()])
   .then(([config, accounts]) => ({
     config,
@@ -23,7 +25,7 @@ function loadLatest (versionId) {
 function loadConfig (versionId) {
   const sql = `select data
   from user_config
-  where versionId=$1 and type=$2`
+  where id=$1 and type=$2`
 
   return db.oneOrNone(sql, [versionId, 'config'])
   .then(row => row ? row.data.config : [])
@@ -33,7 +35,7 @@ function loadLatestConfig () {
   const sql = `select data
   from user_config
   where type=$1
-  order by versionId desc
+  order by id desc
   limit 1`
 
   return db.oneOrNone(sql, ['config'])
diff --git a/lib/ticker.js b/lib/ticker.js
index 446afc33..16754f2f 100644
--- a/lib/ticker.js
+++ b/lib/ticker.js
@@ -1,12 +1,10 @@
 const mem = require('mem')
 const configManager = require('./config-manager')
-const settingsLoader = require('./settings-loader')
 
 const FETCH_INTERVAL = 10000
-function getRates (fiatCode, cryptoCode) {
+function getRates (settings, fiatCode, cryptoCode) {
   return Promise.resolve()
   .then(() => {
-    const settings = settingsLoader.settings()
     const config = settings.config
     const plugin = configManager.cryptoScoped(cryptoCode, config).ticker
 
diff --git a/lib/wallet.js b/lib/wallet.js
index 535c8db1..05cf92dd 100644
--- a/lib/wallet.js
+++ b/lib/wallet.js
@@ -1,13 +1,11 @@
 const mem = require('mem')
 const configManager = require('./config-manager')
-const settingsLoader = require('./settings-loader')
 
 const FETCH_INTERVAL = 5000
 
-function fetchWallet (cryptoCode) {
+function fetchWallet (settings, cryptoCode) {
   return Promise.resolve()
   .then(() => {
-    const settings = settingsLoader.settings()
     const plugin = configManager.cryptoScoped(cryptoCode, settings.config).wallet
     const account = settings.accounts[plugin]
     const wallet = require('lamassu-' + plugin)
@@ -16,14 +14,14 @@ function fetchWallet (cryptoCode) {
   })
 }
 
-function balance (cryptoCode) {
-  return fetchWallet(cryptoCode)
+function balance (settings, cryptoCode) {
+  return fetchWallet(settings, cryptoCode)
   .then(r => r.wallet.balance(r.account, cryptoCode))
   .then(balance => ({balance, timestamp: Date.now()}))
 }
 
-function sendCoins (toAddress, cryptoAtoms, cryptoCode) {
-  return fetchWallet(cryptoCode)
+function sendCoins (settings, toAddress, cryptoAtoms, cryptoCode) {
+  return fetchWallet(settings, cryptoCode)
   .then(r => {
     return r.wallet.sendCoins(r.account, toAddress, cryptoAtoms, cryptoCode)
     .then(res => {
@@ -33,13 +31,13 @@ function sendCoins (toAddress, cryptoAtoms, cryptoCode) {
   })
 }
 
-function newAddress (cryptoCode, info) {
-  return fetchWallet(cryptoCode)
+function newAddress (settings, cryptoCode, info) {
+  return fetchWallet(settings, cryptoCode)
   .then(r => r.wallet.newAddress(r.account, cryptoCode, info))
 }
 
-function getStatus (toAddress, cryptoAtoms, cryptoCode) {
-  return fetchWallet(cryptoCode)
+function getStatus (settings, toAddress, cryptoAtoms, cryptoCode) {
+  return fetchWallet(settings, cryptoCode)
   .then(r => r.wallet.getStatus(r.account, toAddress, cryptoAtoms, cryptoCode))
 }
 
diff --git a/migrations/021-config-version-id.js b/migrations/021-config-version-id.js
new file mode 100644
index 00000000..7a1ba1ce
--- /dev/null
+++ b/migrations/021-config-version-id.js
@@ -0,0 +1,15 @@
+var db = require('./db')
+
+exports.up = function (next) {
+  var sql = [
+    'alter table devices add column user_config_id int',
+    `ALTER TABLE devices ADD CONSTRAINT user_config_id
+    FOREIGN KEY (user_config_id)
+    REFERENCES user_config (id)`
+  ]
+  db.multi(sql, next)
+}
+
+exports.down = function (next) {
+  next()
+}