diff --git a/src/app/credExplorer/App.js b/src/app/credExplorer/App.js
index b61d1dc..f4d22dd 100644
--- a/src/app/credExplorer/App.js
+++ b/src/app/credExplorer/App.js
@@ -3,7 +3,8 @@
 import React from "react";
 import {StyleSheet, css} from "aphrodite/no-important";
 
-import LocalStore from "./LocalStore";
+import type {LocalStore} from "../localStore";
+import BrowserLocalStore from "../browserLocalStore";
 import {StaticPluginAdapter as GithubAdapter} from "../../plugins/github/pluginAdapter";
 import {StaticPluginAdapter as GitAdapter} from "../../plugins/git/pluginAdapter";
 import {Graph} from "../../core/graph";
@@ -16,7 +17,22 @@ import type {PagerankNodeDecomposition} from "../../core/attribution/pagerankNod
 
 import * as NullUtil from "../../util/null";
 
-type Props = {||};
+const REPO_OWNER_KEY = "repoOwner";
+const REPO_NAME_KEY = "repoName";
+const MAX_ENTRIES_PER_LIST = 100;
+
+export default class AppPage extends React.Component<{||}> {
+  static _LOCAL_STORE = new BrowserLocalStore({
+    version: "1",
+    keyPrefix: "cred-explorer",
+  });
+
+  render() {
+    return <App localStore={AppPage._LOCAL_STORE} />;
+  }
+}
+
+type Props = {|+localStore: LocalStore|};
 type State = {
   repoOwner: string,
   repoName: string,
@@ -32,11 +48,7 @@ type State = {
   edgeEvaluator: ?EdgeEvaluator,
 };
 
-const REPO_OWNER_KEY = "repoOwner";
-const REPO_NAME_KEY = "repoName";
-const MAX_ENTRIES_PER_LIST = 100;
-
-export default class App extends React.Component<Props, State> {
+export class App extends React.Component<Props, State> {
   constructor(props: Props) {
     super(props);
     this.state = {
@@ -48,13 +60,15 @@ export default class App extends React.Component<Props, State> {
   }
 
   componentDidMount() {
+    const {localStore} = this.props;
     this.setState((state) => ({
-      repoOwner: LocalStore.get(REPO_OWNER_KEY, state.repoOwner),
-      repoName: LocalStore.get(REPO_NAME_KEY, state.repoName),
+      repoOwner: localStore.get(REPO_OWNER_KEY, state.repoOwner),
+      repoName: localStore.get(REPO_NAME_KEY, state.repoName),
     }));
   }
 
   render() {
+    const {localStore} = this.props;
     const {edgeEvaluator} = this.state;
     const {graphWithMetadata, pnd} = this.state.data;
     return (
@@ -70,7 +84,7 @@ export default class App extends React.Component<Props, State> {
               onChange={(e) => {
                 const value = e.target.value;
                 this.setState({repoOwner: value}, () => {
-                  LocalStore.set(REPO_OWNER_KEY, this.state.repoOwner);
+                  localStore.set(REPO_OWNER_KEY, this.state.repoOwner);
                 });
               }}
             />
@@ -83,7 +97,7 @@ export default class App extends React.Component<Props, State> {
               onChange={(e) => {
                 const value = e.target.value;
                 this.setState({repoName: value}, () => {
-                  LocalStore.set(REPO_NAME_KEY, this.state.repoName);
+                  localStore.set(REPO_NAME_KEY, this.state.repoName);
                 });
               }}
             />
@@ -122,7 +136,10 @@ export default class App extends React.Component<Props, State> {
           ) : (
             <p>Graph not loaded.</p>
           )}
-          <WeightConfig onChange={(ee) => this.setState({edgeEvaluator: ee})} />
+          <WeightConfig
+            localStore={localStore}
+            onChange={(ee) => this.setState({edgeEvaluator: ee})}
+          />
           <PagerankTable
             adapters={NullUtil.map(graphWithMetadata, (x) => x.adapters)}
             pnd={pnd}
diff --git a/src/app/credExplorer/App.test.js b/src/app/credExplorer/App.test.js
index 3f578aa..f631a2c 100644
--- a/src/app/credExplorer/App.test.js
+++ b/src/app/credExplorer/App.test.js
@@ -2,8 +2,9 @@
 import React from "react";
 import {shallow} from "enzyme";
 
+import BrowserLocalStore from "../browserLocalStore";
 import {pagerank} from "../../core/attribution/pagerank";
-import App from "./App";
+import {App} from "./App";
 
 import {Graph, NodeAddress, EdgeAddress} from "../../core/graph";
 
@@ -95,17 +96,27 @@ function example() {
 }
 
 describe("app/credExplorer/App", () => {
+  function makeLocalStore() {
+    // TODO(@wchargin): This should be an in-memory implementation of
+    // LocalStore, not the browser version. This only works because the
+    // store is not actually needed for the shallow render to complete
+    // successfully.
+    return new BrowserLocalStore({
+      version: "1",
+      keyPrefix: "cred-explorer",
+    });
+  }
   it("renders with clean state", () => {
-    shallow(<App />);
+    shallow(<App localStore={makeLocalStore()} />);
   });
   it("renders with graph and adapters set", () => {
-    const app = shallow(<App />);
+    const app = shallow(<App localStore={makeLocalStore()} />);
     const {graph, adapters} = example();
     const data = {graph, adapters, pagerankResult: null};
     app.setState({data});
   });
   it("renders with graph and adapters and pagerankResult", () => {
-    const app = shallow(<App />);
+    const app = shallow(<App localStore={makeLocalStore()} />);
     const {graph, adapters, pagerankResult} = example();
     const data = {graph, adapters, pagerankResult};
     app.setState({data});
diff --git a/src/app/credExplorer/LocalStore.js b/src/app/credExplorer/LocalStore.js
deleted file mode 100644
index 9457f45..0000000
--- a/src/app/credExplorer/LocalStore.js
+++ /dev/null
@@ -1,5 +0,0 @@
-// @flow
-
-import LocalStore from "../browserLocalStore";
-
-export default new LocalStore({version: "1", keyPrefix: "cred-explorer"});
diff --git a/src/app/credExplorer/WeightConfig.js b/src/app/credExplorer/WeightConfig.js
index 606c0b1..db5b34b 100644
--- a/src/app/credExplorer/WeightConfig.js
+++ b/src/app/credExplorer/WeightConfig.js
@@ -9,9 +9,9 @@ import {
   NodeAddress,
 } from "../../core/graph";
 
+import type {LocalStore} from "../localStore";
 import {type EdgeEvaluator} from "../../core/attribution/pagerank";
 import {byEdgeType, byNodeType} from "./edgeWeights";
-import LocalStore from "./LocalStore";
 import * as MapUtil from "../../util/map";
 import * as NullUtil from "../../util/null";
 
@@ -19,9 +19,10 @@ import type {StaticPluginAdapter} from "../pluginAdapter";
 import {StaticPluginAdapter as GithubAdapter} from "../../plugins/github/pluginAdapter";
 import {StaticPluginAdapter as GitAdapter} from "../../plugins/git/pluginAdapter";
 
-type Props = {
-  onChange: (EdgeEvaluator) => void,
-};
+type Props = {|
+  +localStore: LocalStore,
+  +onChange: (EdgeEvaluator) => void,
+|};
 
 type EdgeWeights = Map<EdgeAddressT, UserEdgeWeight>;
 type UserEdgeWeight = {|+logWeight: number, +directionality: number|};
@@ -71,15 +72,16 @@ export class WeightConfig extends React.Component<Props, State> {
   }
 
   componentDidMount() {
+    const {localStore} = this.props;
     this.setState(
       (state) => {
         return {
           edgeWeights: NullUtil.orElse(
-            NullUtil.map(LocalStore.get(EDGE_WEIGHTS_KEY), MapUtil.fromObject),
+            NullUtil.map(localStore.get(EDGE_WEIGHTS_KEY), MapUtil.fromObject),
             state.edgeWeights
           ),
           nodeWeights: NullUtil.orElse(
-            NullUtil.map(LocalStore.get(NODE_WEIGHTS_KEY), MapUtil.fromObject),
+            NullUtil.map(localStore.get(NODE_WEIGHTS_KEY), MapUtil.fromObject),
             state.nodeWeights
           ),
         };
@@ -126,9 +128,10 @@ export class WeightConfig extends React.Component<Props, State> {
   }
 
   fire() {
+    const {localStore} = this.props;
     const {edgeWeights, nodeWeights} = this.state;
-    LocalStore.set(EDGE_WEIGHTS_KEY, MapUtil.toObject(edgeWeights));
-    LocalStore.set(NODE_WEIGHTS_KEY, MapUtil.toObject(nodeWeights));
+    localStore.set(EDGE_WEIGHTS_KEY, MapUtil.toObject(edgeWeights));
+    localStore.set(NODE_WEIGHTS_KEY, MapUtil.toObject(nodeWeights));
     const edgePrefixes = Array.from(edgeWeights.entries()).map(
       ([prefix, {logWeight, directionality}]) => ({
         prefix,