diff --git a/circle.yml b/circle.yml
index e82ee45..05f4348 100644
--- a/circle.yml
+++ b/circle.yml
@@ -1,16 +1,15 @@
 machine:
+    pre:
+        - echo export PERCY_PARALLEL_NONCE=$CIRCLE_BUILD_NUM >> $HOME/.circlerc
+
     node:
         version: 6.9.2
     post:
-        - pyenv global 2.7.10 3.3.6 3.4.4 3.5.3 3.6.2
+        - pyenv global 2.7.10 3.6.2
     environment:
         TOX_PYTHON_27: python2.7
-        TOX_PYTHON_33: python3.3
-        TOX_PYTHON_34: python3.4
-        TOX_PYTHON_35: python3.5
         TOX_PYTHON_36: python3.6
 
-
 dependencies:
     pre:
         - pip install tox
diff --git a/dash_renderer/__init__.py b/dash_renderer/__init__.py
index d9005d0..0b15ec2 100644
--- a/dash_renderer/__init__.py
+++ b/dash_renderer/__init__.py
@@ -30,9 +30,9 @@
     {
         'relative_package_path': 'bundle.js',
         "external_url": (
-            'https://unpkg.com/dash-renderer@{}'
+            'https://unpkg.com/dash-renderer@0.10.0-rc1'
             '/dash_renderer/bundle.js'
-        ).format(__version__),
+        ),
         'namespace': 'dash_renderer'
     }
 ]
diff --git a/dash_renderer/version.py b/dash_renderer/version.py
index e4e49b3..366d751 100644
--- a/dash_renderer/version.py
+++ b/dash_renderer/version.py
@@ -1 +1 @@
-__version__ = '0.9.0'
+__version__ = '0.10.0rc1'
diff --git a/dev-requirements.txt b/dev-requirements.txt
index 0055fd7..df68515 100644
--- a/dev-requirements.txt
+++ b/dev-requirements.txt
@@ -1,6 +1,6 @@
 dash_core_components==0.12.0
 dash_html_components==0.7.0
-dash==0.18.0
+dash==0.18.3
 percy
 selenium
 mock
diff --git a/package.json b/package.json
index 0ae02e3..d17b6fe 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "dash-renderer",
-  "version": "0.9.0",
+  "version": "0.10.0-rc1",
   "description": "render dash components in react",
   "main": "src/index.js",
   "scripts": {
diff --git a/src/actions/index.js b/src/actions/index.js
index 956334f..6da1100 100644
--- a/src/actions/index.js
+++ b/src/actions/index.js
@@ -7,7 +7,9 @@ import {
     isEmpty,
     keys,
     lensPath,
+    pluck,
     reject,
+    slice,
     sort,
     type,
     union,
@@ -40,10 +42,10 @@ function triggerDefaultState(dispatch, getState) {
     const {graphs} = getState();
     const {InputGraph} = graphs;
     const allNodes = InputGraph.overallOrder();
+    const inputNodeIds = [];
     allNodes.reverse();
     allNodes.forEach(nodeId => {
-        const [componentId, componentProp] = nodeId.split('.');
-
+        const componentId = nodeId.split('.')[0];
         /*
          * Filter out the outputs,
          * inputs that aren't leaves,
@@ -53,24 +55,28 @@ function triggerDefaultState(dispatch, getState) {
             InputGraph.dependantsOf(nodeId).length == 0 &&
             has(componentId, getState().paths)
         ) {
+            inputNodeIds.push(nodeId);
+        }
+    });
 
-            // Get the initial property
-            const propLens = lensPath(
-                concat(getState().paths[componentId],
-                ['props', componentProp]
-            ));
-            const propValue = view(
-                propLens,
-                getState().layout
-            );
-
-            dispatch(notifyObservers({
-                id: componentId,
-                props: {[componentProp]: propValue}
-            }));
+    reduceInputIds(inputNodeIds, InputGraph).forEach(nodeId => {
+        const [componentId, componentProp] = nodeId.split('.');
+        // Get the initial property
+        const propLens = lensPath(
+            concat(getState().paths[componentId],
+            ['props', componentProp]
+        ));
+        const propValue = view(
+            propLens,
+            getState().layout
+        );
 
-        }
+        dispatch(notifyObservers({
+            id: componentId,
+            props: {[componentProp]: propValue}
+        }));
     });
+
 }
 
 export function redo() {
@@ -116,6 +122,31 @@ export function undo() {
 
 
 
+function reduceInputIds(nodeIds, InputGraph) {
+    /*
+     * Create input-output(s) pairs,
+     * sort by number of outputs,
+     * and remove redudant inputs (inputs that update the same output)
+     */
+    const inputOutputPairs = nodeIds.map(nodeId => ({
+        input: nodeId,
+        outputs: InputGraph.dependenciesOf(nodeId)
+    }));
+
+    const sortedInputOutputPairs = sort(
+        (a, b) => b.outputs.length - a.outputs.length,
+        inputOutputPairs
+    );
+
+    const uniquePairs = sortedInputOutputPairs.filter((pair, i) => !contains(
+        pair.outputs,
+        pluck('outputs', slice(i + 1, Infinity, sortedInputOutputPairs))
+    ));
+
+    return pluck('input', uniquePairs);
+}
+
+
 
 export function notifyObservers(payload) {
     return function (dispatch, getState) {
@@ -136,7 +167,6 @@ export function notifyObservers(payload) {
         const {EventGraph, InputGraph} = graphs;
 
         /*
-
          * Figure out all of the output id's that depend on this
          * event or input.
          * This includes id's that are direct children as well as
@@ -394,7 +424,7 @@ export function notifyObservers(payload) {
                              * We don't need to do this - just need
                              * to compute the subtree
                              */
-                            const newProps = [];
+                            const newProps = {};
                             crawlLayout(
                                 observerUpdatePayload.props.children,
                                 function appendIds(child) {
@@ -404,7 +434,7 @@ export function notifyObservers(payload) {
                                                 `${child.props.id}.${childProp}`
                                             );
                                             if (has(inputId, InputGraph.nodes)) {
-                                                newProps.push({
+                                                newProps[inputId] = ({
                                                     id: child.props.id,
                                                     props: {
                                                         [childProp]: child.props[childProp]
@@ -416,21 +446,20 @@ export function notifyObservers(payload) {
                                 }
                             );
 
+                            /*
+                             * Organize props by shared outputs so that we
+                             * only make one request per output component
+                             * (even if there are multiple inputs).
+                             */
+                            const reducedNodeIds = reduceInputIds(
+                                keys(newProps), InputGraph);
                             const depOrder = InputGraph.overallOrder();
                             const sortedNewProps = sort((a, b) =>
-                                depOrder.indexOf(a.id) - depOrder.indexOf(b.id),
-                                newProps
+                                depOrder.indexOf(a) - depOrder.indexOf(b),
+                                reducedNodeIds
                             );
-
-                            /*
-                             * TODO - As in the case of Jack Luo's indicator app,
-                             * all of these inputs could update a _single_ output.
-                             * If that is the case, then we can collect all of their
-                             * values and make a single request instead of making a
-                             * different request for each input
-                             */
-                            sortedNewProps.forEach(function(propUpdate) {
-                                dispatch(notifyObservers(propUpdate));
+                            sortedNewProps.forEach(function(nodeId) {
+                                dispatch(notifyObservers(newProps[nodeId]));
                             });
 
                         }
diff --git a/tests/IntegrationTests.py b/tests/IntegrationTests.py
index 4951e40..2730336 100644
--- a/tests/IntegrationTests.py
+++ b/tests/IntegrationTests.py
@@ -9,12 +9,25 @@
 import percy
 import time
 import unittest
+import os
+import sys
 
 
 class IntegrationTests(unittest.TestCase):
 
+    def percy_snapshot(cls, name=''):
+        snapshot_name = '{} - {}'.format(name, sys.version_info)
+        print(snapshot_name)
+        cls.percy_runner.snapshot(
+            name=snapshot_name
+        )
+
     @classmethod
     def setUpClass(cls):
+        print('PERCY_PARALLEL_NONCE')
+        print(os.environ['PERCY_PARALLEL_NONCE'])
+        print('PERCY_PARALLEL_TOTAL')
+        print(os.environ['PERCY_PARALLEL_TOTAL'])
         super(IntegrationTests, cls).setUpClass()
         cls.driver = webdriver.Chrome()
 
@@ -25,6 +38,7 @@ def setUpClass(cls):
 
         cls.percy_runner.initialize_build()
 
+
     @classmethod
     def tearDownClass(cls):
         super(IntegrationTests, cls).tearDownClass()
diff --git a/tests/test_render.py b/tests/test_render.py
index 9ca4265..093313d 100644
--- a/tests/test_render.py
+++ b/tests/test_render.py
@@ -9,6 +9,7 @@
 import time
 import re
 import itertools
+import json
 
 
 class Tests(IntegrationTests):
@@ -391,7 +392,7 @@ def test_initial_state(self):
             []
         )
 
-        self.percy_runner.snapshot(name='layout')
+        self.percy_snapshot(name='layout')
 
         assert_clean_console(self)
 
@@ -423,7 +424,7 @@ def update_output(value):
 
         output1 = self.wait_for_element_by_id('output-1')
         wait_for(lambda: output1.text == 'initial value')
-        self.percy_runner.snapshot(name='simple-callback-1')
+        self.percy_snapshot(name='simple-callback-1')
 
         input1 = self.wait_for_element_by_id('input')
         input1.clear()
@@ -432,7 +433,7 @@ def update_output(value):
 
         output1 = lambda: self.wait_for_element_by_id('output-1')
         wait_for(lambda: output1().text == 'hello world')
-        self.percy_runner.snapshot(name='simple-callback-2')
+        self.percy_snapshot(name='simple-callback-2')
 
         self.assertEqual(
             call_count.value,
@@ -510,7 +511,7 @@ def update_input(value):
                 </div>'''.replace('\n', '').replace('  ', '')
             )
         )
-        self.percy_runner.snapshot(name='callback-generating-function-1')
+        self.percy_snapshot(name='callback-generating-function-1')
 
         # the paths should include these new output IDs
         self.assertEqual(
@@ -550,7 +551,7 @@ def update_input(value):
             ),
             []
         )
-        self.percy_runner.snapshot(name='callback-generating-function-2')
+        self.percy_snapshot(name='callback-generating-function-2')
 
         assert_clean_console(self)
 
@@ -766,7 +767,7 @@ def chapter1_assertions():
             generic_chapter_assertions('chapter1')
 
         chapter1_assertions()
-        self.percy_runner.snapshot(name='chapter-1')
+        self.percy_snapshot(name='chapter-1')
 
         # switch chapters
         (self.driver.find_elements_by_css_selector(
@@ -775,7 +776,7 @@ def chapter1_assertions():
 
         # sleep just to make sure that no calls happen after our check
         time.sleep(2)
-        self.percy_runner.snapshot(name='chapter-2')
+        self.percy_snapshot(name='chapter-2')
         wait_for(lambda: call_counts['body'].value == 2)
         wait_for(lambda: call_counts['chapter2-graph'].value == 1)
         wait_for(lambda: call_counts['chapter2-label'].value == 1)
@@ -820,7 +821,7 @@ def chapter2_assertions():
         )[2]).click()
         # sleep just to make sure that no calls happen after our check
         time.sleep(2)
-        self.percy_runner.snapshot(name='chapter-3')
+        self.percy_snapshot(name='chapter-3')
         wait_for(lambda: call_counts['body'].value == 3)
         wait_for(lambda: call_counts['chapter3-graph'].value == 1)
         wait_for(lambda: call_counts['chapter3-label'].value == 1)
@@ -873,7 +874,7 @@ def chapter3_assertions():
             self.driver.find_element_by_id('body').text ==
             'Just a string'
         ))
-        self.percy_runner.snapshot(name='chapter-4')
+        self.percy_snapshot(name='chapter-4')
 
         # each element should exist in the dom
         paths = self.driver.execute_script(
@@ -892,7 +893,7 @@ def chapter3_assertions():
         )[0]).click()
         time.sleep(0.5)
         chapter1_assertions()
-        self.percy_runner.snapshot(name='chapter-1-again')
+        self.percy_snapshot(name='chapter-1-again')
 
         # switch to 5
         (self.driver.find_elements_by_css_selector(
@@ -910,7 +911,7 @@ def chapter3_assertions():
         chapter5_button().click()
         wait_for(lambda: chapter5_div().text == chapter5_output_children)
         time.sleep(0.5)
-        self.percy_runner.snapshot(name='chapter-5')
+        self.percy_snapshot(name='chapter-5')
         self.assertEqual(call_counts['chapter5-output'].value, 1)
 
     def test_dependencies_on_components_that_dont_exist(self):
@@ -945,7 +946,7 @@ def update_output_2(value):
 
         el = self.wait_for_element_by_id('output-1')
         wait_for(lambda: el.text == 'initial value')
-        self.percy_runner.snapshot(name='dependencies')
+        self.percy_snapshot(name='dependencies')
         time.sleep(1.0)
         self.assertEqual(output_1_call_count.value, 1)
         self.assertEqual(output_2_call_count.value, 0)
@@ -1415,3 +1416,88 @@ def chapter2_assertions():
         time.sleep(2)  # liberally wait for the front-end to process request
         chapter2_assertions()
         assert_clean_console(self)
+
+    def test_rendering_layout_calls_callback_once_per_output(self):
+        app = Dash(__name__)
+        call_count = Value('i', 0)
+
+        app.config['suppress_callback_exceptions'] = True
+        app.layout = html.Div([
+            html.Div([
+                dcc.Input(
+                    value='Input {}'.format(i),
+                    id='input-{}'.format(i)
+                )
+                for i in range(10)
+            ]),
+            html.Div(id='container'),
+            dcc.RadioItems()
+        ])
+
+        @app.callback(
+            Output('container', 'children'),
+            [Input('input-{}'.format(i), 'value') for i in range(10)])
+        def dynamic_output(*args):
+            call_count.value += 1
+            return json.dumps(args, indent=2)
+
+        self.startServer(app)
+
+        time.sleep(5)
+
+        self.percy_snapshot(
+            name='test_rendering_layout_calls_callback_once_per_output'
+        )
+
+        self.assertEqual(call_count.value, 1)
+
+    def test_rendering_new_content_calls_callback_once_per_output(self):
+        app = Dash(__name__)
+        call_count = Value('i', 0)
+
+        app.config['suppress_callback_exceptions'] = True
+        app.layout = html.Div([
+            html.Button(
+                id='display-content',
+                children='Display Content',
+                n_clicks=0
+            ),
+            html.Div(id='container'),
+            dcc.RadioItems()
+        ])
+
+        @app.callback(
+            Output('container', 'children'),
+            [Input('display-content', 'n_clicks')])
+        def display_output(n_clicks):
+            if n_clicks == 0:
+                return ''
+            return html.Div([
+                html.Div([
+                    dcc.Input(
+                        value='Input {}'.format(i),
+                        id='input-{}'.format(i)
+                    )
+                    for i in range(10)
+                ]),
+                html.Div(id='dynamic-output')
+            ])
+
+        @app.callback(
+            Output('dynamic-output', 'children'),
+            [Input('input-{}'.format(i), 'value') for i in range(10)])
+        def dynamic_output(*args):
+            call_count.value += 1
+            return json.dumps(args, indent=2)
+
+        self.startServer(app)
+
+        self.wait_for_element_by_id('display-content').click()
+
+        time.sleep(5)
+
+        self.percy_snapshot(
+            name='test_rendering_new_content_calls_callback_once_per_output'
+        )
+
+        self.assertEqual(call_count.value, 1)
diff --git a/tox.ini b/tox.ini
index 1462ab1..d448499 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,5 +1,5 @@
 [tox]
-envlist = py27,py33,py34,py35
+envlist = py27,py36
 
 [testenv]
 deps = -rdev-requirements.txt
@@ -7,35 +7,20 @@ deps = -rdev-requirements.txt
 passenv = *
 
 [testenv:py27]
-basepython={env:TOX_PYTHON_27}
-commands =
-    python --version
-    python -m unittest tests.test_render.Tests
-    python -m unittest tests.test_race_conditions.Tests
-
-[testenv:py33]
-basepython={env:TOX_PYTHON_33}
-commands =
-    python --version
-    python -m unittest tests.test_render.Tests
-    python -m unittest tests.test_race_conditions.Tests
-
-[testenv:py34]
-basepython={env:TOX_PYTHON_34}
-commands =
-    python --version
-    python -m unittest tests.test_render.Tests
-    python -m unittest tests.test_race_conditions.Tests
-
-[testenv:py35]
-basepython={env:TOX_PYTHON_35}
+basepython =
+    {env:TOX_PYTHON_27}
+setenv =
+    PERCY_PARALLEL_TOTAL=4
 commands =
     python --version
     python -m unittest tests.test_render.Tests
     python -m unittest tests.test_race_conditions.Tests
 
 [testenv:py36]
-basepython={env:TOX_PYTHON_36}
+basepython =
+    {env:TOX_PYTHON_36}
+setenv =
+    PERCY_PARALLEL_TOTAL=4
 commands =
     python --version
     python -m unittest tests.test_render.Tests