diff --git a/src/config/config.ts b/src/config/config.ts
index 28243c5db..27161da6a 100644
--- a/src/config/config.ts
+++ b/src/config/config.ts
@@ -317,13 +317,6 @@ function setBaseDeltas(app: ConfigApp) {
   return true
 }
 
-export function sendBaseDeltas(app: ConfigApp) {
-  const copy = JSON.parse(JSON.stringify(app.config.baseDeltaEditor.deltas))
-  copy.forEach((delta: any) => {
-    app.handleMessage('defaults', delta)
-  })
-}
-
 function writeDefaultsFile(app: ConfigApp, defaults: any, cb: any) {
   fs.writeFile(getDefaultsPath(app), JSON.stringify(defaults, null, 2), cb)
 }
@@ -336,7 +329,7 @@ function writeBaseDeltasFile(app: ConfigApp) {
   return app.config.baseDeltaEditor.save(getBaseDeltasPath(app))
 }
 
-function setSelfSettings(app: ConfigApp) {
+async function setSelfSettings(app: ConfigApp) {
   const name = app.config.baseDeltaEditor.getSelfValue('name')
   const mmsi = app.config.baseDeltaEditor.getSelfValue('mmsi')
   let uuid = app.config.baseDeltaEditor.getSelfValue('uuid')
@@ -352,6 +345,7 @@ function setSelfSettings(app: ConfigApp) {
   if (mmsi === null && uuid === null) {
     uuid = 'urn:mrn:signalk:uuid:' + uuidv4()
     app.config.baseDeltaEditor.setSelfValue('uuid', uuid)
+    await writeBaseDeltasFile(app)
   }
 
   app.config.vesselName = name
@@ -488,6 +482,5 @@ module.exports = {
   writeSettingsFile,
   writeDefaultsFile,
   readDefaultsFile,
-  sendBaseDeltas,
   writeBaseDeltasFile
 }
diff --git a/src/deltaeditor.ts b/src/deltaeditor.ts
index e082e6fc0..8f9ab5e8f 100644
--- a/src/deltaeditor.ts
+++ b/src/deltaeditor.ts
@@ -22,12 +22,22 @@ const META = 'meta'
 const SELF_VESSEL = 'vessels.self'
 
 class DeltaEditor {
-  deltas: any[]
+  private deltas: any[]
 
   constructor() {
     this.deltas = []
   }
 
+  getDeltas() {
+    return JSON.parse(JSON.stringify(this.deltas))
+  }
+
+  sendDeltas(handleMessage: (id: string, delta: any) => void) {
+    this.getDeltas().forEach((delta: any) => {
+      handleMessage('defaults', delta)
+    })
+  }
+
   load(filename: string) {
     const data = fs.readFileSync(filename, 'utf8')
     const deltas = JSON.parse(data)
diff --git a/src/index.ts b/src/index.ts
index 3c761ca0f..3ad35e76c 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -28,7 +28,7 @@ import https from 'https'
 import _ from 'lodash'
 import path from 'path'
 import { SelfIdentity, ServerApp, SignalKMessageHub, WithConfig } from './app'
-import { ConfigApp, load, sendBaseDeltas } from './config/config'
+import { load } from './config/config'
 import { createDebug } from './debug'
 import DeltaCache from './deltacache'
 import DeltaChain, { DeltaInputHandler } from './deltachain'
@@ -245,6 +245,9 @@ class Server {
     app.on('nmea2000OutAvailable', () => {
       app.isNmea2000OutAvailable = true
     })
+
+    app.sendBaseDeltas = () =>
+      app.config.baseDeltaEditor.sendDeltas(app.handleMessage)
   }
 
   start() {
@@ -360,7 +363,7 @@ class Server {
         debug('ID type: ' + app.selfType)
         debug('ID: ' + app.selfId)
 
-        sendBaseDeltas((app as unknown) as ConfigApp)
+        app.config.baseDeltaEditor.sendDeltas(app.handleMessage)
 
         startInterfaces(app)
         startMdns(app)
diff --git a/src/put.js b/src/put.js
index eb6566215..1570a61f2 100644
--- a/src/put.js
+++ b/src/put.js
@@ -1,7 +1,6 @@
 const _ = require('lodash')
 import { createDebug } from './debug'
 const debug = createDebug('signalk-server:put')
-const { v4: uuidv4 } = require('uuid')
 const { createRequest, updateRequest } = require('./requestResponse')
 const skConfig = require('./config/config')
 
@@ -81,7 +80,7 @@ module.exports = {
       }
 
       app.config.baseDeltaEditor.setMeta(context, metaPath, metaValue)
-      skConfig.sendBaseDeltas(app)
+      app.sendBaseDeltas()
 
       if (app.config.hasOldDefaults) {
         let data
diff --git a/src/serverroutes.js b/src/serverroutes.js
index bb9b2424b..ac092cd93 100644
--- a/src/serverroutes.js
+++ b/src/serverroutes.js
@@ -17,7 +17,6 @@
 const fs = require('fs')
 const os = require('os')
 const readdir = require('util').promisify(fs.readdir)
-const page = require('./page')
 import { createDebug, listKnownDebugs } from './debug'
 const debug = createDebug('signalk-server:serverroutes')
 const path = require('path')
@@ -40,6 +39,9 @@ const defaultSecurityStrategy = './tokensecurity'
 const skPrefix = '/signalk/v1'
 import { SERVERROUTESPREFIX } from './constants'
 
+const MMSIPATTERN = /^\d{9}$/
+const UUIDPATTERN = /^urn:mrn:signalk:uuid:[0-9A-Fa-f]{8}-[0-9A-Fa-f]{4}-4[0-9A-Fa-f]{3}-[89ABab][0-9A-Fa-f]{3}-[0-9A-Fa-f]{12}$/
+
 module.exports = function(app, saveSecurityConfig, getSecurityConfig) {
   let securityWasEnabled
   let restoreFilePath
@@ -638,10 +640,27 @@ module.exports = function(app, saveSecurityConfig, getSecurityConfig) {
     })
   }
 
-  app.put(`${SERVERROUTESPREFIX}/vessel`, (req, res, next) => {
+  app.put(`${SERVERROUTESPREFIX}/vessel`, (req, res) => {
+    console.log(JSON.stringify(req.body, null, 2))
     const de = app.config.baseDeltaEditor
     let vessel = req.body
 
+    if (!vessel.mmsi && !vessel.uuid) {
+      res.status(400)
+      res.send(`You must provide either mmsi or uuid`)
+      return
+    }
+    if (vessel.mmsi && !vessel.mmsi.match(MMSIPATTERN)) {
+      res.status(400)
+      res.send(`MMSI must be a number with 9 digits`)
+      return
+    }
+    if (vessel.uuid && !vessel.uuid.match(UUIDPATTERN)) {
+      res.status(400)
+      res.send(`Uuid must be a v4 UUID with prefix urn:mrn:signalk:uuid:`)
+      return
+    }
+
     de.setSelfValue('name', vessel.name)
     app.config.vesselName = vessel.name
     de.setSelfValue('mmsi', vessel.mmsi)
@@ -701,7 +720,7 @@ module.exports = function(app, saveSecurityConfig, getSecurityConfig) {
       }
     })
 
-    skConfig.sendBaseDeltas(app)
+    app.sendBaseDeltas()
 
     if (app.config.hasOldDefaults) {
       writeOldDefaults(req, res)