diff --git a/internal_packages/worker-sync/lib/nylas-long-connection.coffee b/internal_packages/worker-sync/lib/nylas-long-connection.coffee
index e54b2745b..3ead7cb4d 100644
--- a/internal_packages/worker-sync/lib/nylas-long-connection.coffee
+++ b/internal_packages/worker-sync/lib/nylas-long-connection.coffee
@@ -11,10 +11,10 @@ class NylasLongConnection
     Connected: 'connected'
     Retrying: 'retrying'
 
-  constructor: (api, accountId) ->
+  constructor: (api, accountId, config) ->
     @_api = api
     @_accountId = accountId
-    @_cursorKey = "nylas.#{@_accountId}.cursor"
+    @_config = config
     @_emitter = new Emitter
     @_state = 'idle'
     @_req = null
@@ -28,10 +28,9 @@ class NylasLongConnection
       last = @_deltas[@_deltas.length - 1]
 
       @_emitter.emit('deltas-stopped-arriving', @_deltas)
+      @_config.setCursor(last.cursor)
       @_deltas = []
 
-      # Note: setCursor is slow and saves to disk, so we do it once at the end
-      @setCursor(last.cursor)
     , 1000
 
     @
@@ -40,10 +39,10 @@ class NylasLongConnection
     @_accountId
 
   hasCursor: ->
-    !!NylasEnv.config.get(@_cursorKey)
+    !!@_config.getCursor()
 
   withCursor: (callback) ->
-    cursor = NylasEnv.config.get(@_cursorKey)
+    cursor = @_config.getCursor()
     return callback(cursor) if cursor
 
     @_api.makeRequest
@@ -52,12 +51,9 @@ class NylasLongConnection
       method: 'POST'
       success: ({cursor}) =>
         console.log("Obtained stream cursor #{cursor}.")
-        @setCursor(cursor)
+        @_config.setCursor(cursor)
         callback(cursor)
 
-  setCursor: (cursor) ->
-    NylasEnv.config.set(@_cursorKey, cursor)
-
   state: ->
     @state
 
@@ -92,6 +88,8 @@ class NylasLongConnection
         @_flushDeltasDebounced()
 
   start: ->
+    return unless @_config.ready()
+
     token = @_api.accessTokenForAccountId(@_accountId)
     return if not token?
     return if @_state is NylasLongConnection.State.Ended
diff --git a/internal_packages/worker-sync/lib/nylas-sync-worker.coffee b/internal_packages/worker-sync/lib/nylas-sync-worker.coffee
index 326ecd0e9..c9332af33 100644
--- a/internal_packages/worker-sync/lib/nylas-sync-worker.coffee
+++ b/internal_packages/worker-sync/lib/nylas-sync-worker.coffee
@@ -42,7 +42,16 @@ class NylasSyncWorker
     @_account = account
 
     @_terminated = false
-    @_connection = new NylasLongConnection(api, account.id)
+    @_connection = new NylasLongConnection(api, account.id, {
+      ready: => @_state isnt null
+      getCursor: =>
+        return null if @_state is null
+        @_state['cursor'] || NylasEnv.config.get("nylas.#{@_account.id}.cursor")
+      setCursor: (val) =>
+        @_state['cursor'] = val
+        @writeState()
+    })
+
     @_refreshingCaches = [new ContactRankingsCache(account.id)]
     @_resumeTimer = new BackoffTimer =>
       # indirection needed so resumeFetches can be spied on
@@ -53,9 +62,10 @@ class NylasSyncWorker
     @_state = null
     DatabaseStore.findJSONBlob("NylasSyncWorker:#{@_account.id}").then (json) =>
       @_state = json ? {}
-      for model, modelState of @_state
-        modelState.busy = false
+      for key in ['threads', 'labels', 'folders', 'drafts', 'contacts', 'calendars', 'events']
+        @_state[key].busy = false if @_state[key]
       @resumeFetches()
+      @_connection.start()
 
     @
 
diff --git a/internal_packages/worker-sync/spec/nylas-sync-worker-spec.coffee b/internal_packages/worker-sync/spec/nylas-sync-worker-spec.coffee
index f972bf907..bff7365bf 100644
--- a/internal_packages/worker-sync/spec/nylas-sync-worker-spec.coffee
+++ b/internal_packages/worker-sync/spec/nylas-sync-worker-spec.coffee
@@ -16,10 +16,12 @@ describe "NylasSyncWorker", ->
       getThreads: (account, params, requestOptions) =>
         @apiRequests.push({account, model:'threads', params, requestOptions})
 
+    @apiCursorStub = undefined
     spyOn(DatabaseTransaction.prototype, 'persistJSONBlob').andReturn(Promise.resolve())
     spyOn(DatabaseStore, 'findJSONBlob').andCallFake (key) =>
       if key is "NylasSyncWorker:#{TEST_ACCOUNT_ID}"
         return Promise.resolve _.extend {}, {
+          "cursor": @apiCursorStub
           "contacts":
             busy: true
             complete: false
@@ -36,6 +38,7 @@ describe "NylasSyncWorker", ->
     @account = new Account(clientId: TEST_ACCOUNT_CLIENT_ID, serverId: TEST_ACCOUNT_ID, organizationUnit: 'label')
     @worker = new NylasSyncWorker(@api, @account)
     @connection = @worker.connection()
+    spyOn(@connection, 'start')
     advanceClock()
 
   it "should reset `busy` to false when reading state from disk", ->
@@ -46,13 +49,11 @@ describe "NylasSyncWorker", ->
 
   describe "start", ->
     it "should open the delta connection", ->
-      spyOn(@connection, 'start')
       @worker.start()
       advanceClock()
       expect(@connection.start).toHaveBeenCalled()
 
     it "should start querying for model collections and counts that haven't been fully cached", ->
-      spyOn(@connection, 'start')
       @worker.start()
       advanceClock()
       expect(@apiRequests.length).toBe(10)
@@ -129,6 +130,40 @@ describe "NylasSyncWorker", ->
       advanceClock(30000)
       expect(@worker.resumeFetches.callCount).toBe(1)
 
+  describe "delta streaming cursor", ->
+    it "should read the cursor from the database, and the old config format", ->
+      spyOn(NylasLongConnection.prototype, 'withCursor').andCallFake =>
+
+      @apiCursorStub = undefined
+
+      # no cursor present
+      worker = new NylasSyncWorker(@api, @account)
+      connection = worker.connection()
+      expect(connection.hasCursor()).toBe(false)
+      advanceClock()
+      expect(connection.hasCursor()).toBe(false)
+
+      # cursor present in config
+      spyOn(NylasEnv.config, 'get').andCallFake (key) =>
+        return 'old-school' if key is "nylas.#{@account.id}.cursor"
+        return undefined
+
+      worker = new NylasSyncWorker(@api, @account)
+      connection = worker.connection()
+      advanceClock()
+      expect(connection.hasCursor()).toBe(true)
+      expect(connection._config.getCursor()).toEqual('old-school')
+
+      # cursor present in database, overrides cursor in config
+      @apiCursorStub = "new-school"
+
+      worker = new NylasSyncWorker(@api, @account)
+      connection = worker.connection()
+      expect(connection.hasCursor()).toBe(false)
+      advanceClock()
+      expect(connection.hasCursor()).toBe(true)
+      expect(connection._config.getCursor()).toEqual('new-school')
+
   describe "when a count request completes", ->
     beforeEach ->
       @worker.start()