diff --git a/.eslintrc.json b/.eslintrc.json
index 7f352ef371..2353192134 100644
--- a/.eslintrc.json
+++ b/.eslintrc.json
@@ -135,7 +135,6 @@
                 "buddy_data": false,
                 "buddy_list": false,
                 "click_handlers": false,
-                "color_data": false,
                 "compose_actions": false,
                 "compose_ui": false,
                 "composebox_typeahead": false,
diff --git a/frontend_tests/node_tests/color_data.js b/frontend_tests/node_tests/color_data.js
index 40a6b9edbb..db58305b2b 100644
--- a/frontend_tests/node_tests/color_data.js
+++ b/frontend_tests/node_tests/color_data.js
@@ -8,7 +8,7 @@ const {run_test} = require("../zjsunit/test");
 const color_data = zrequire("color_data");
 
 run_test("pick_color", () => {
-    color_data.colors = ["blue", "orange", "red", "yellow"];
+    color_data.__Rewire__("colors", ["blue", "orange", "red", "yellow"]);
 
     color_data.reset();
 
diff --git a/frontend_tests/node_tests/stream_data.js b/frontend_tests/node_tests/stream_data.js
index 52037cc01b..651da9841e 100644
--- a/frontend_tests/node_tests/stream_data.js
+++ b/frontend_tests/node_tests/stream_data.js
@@ -653,7 +653,7 @@ run_test("create_sub", () => {
         color: "#76ce90",
     };
 
-    color_data.pick_color = () => "#bd86e5";
+    color_data.__Rewire__("pick_color", () => "#bd86e5");
 
     const india_sub = stream_data.create_sub_from_server_data(india);
     assert(india_sub);
diff --git a/frontend_tests/node_tests/stream_events.js b/frontend_tests/node_tests/stream_events.js
index 511659433f..11049f676c 100644
--- a/frontend_tests/node_tests/stream_events.js
+++ b/frontend_tests/node_tests/stream_events.js
@@ -2,6 +2,8 @@
 
 const {strict: assert} = require("assert");
 
+const rewiremock = require("rewiremock/node");
+
 const {set_global, zrequire} = require("../zjsunit/namespace");
 const {make_stub} = require("../zjsunit/stub");
 const {run_test} = require("../zjsunit/test");
@@ -13,7 +15,8 @@ const _settings_notifications = {
 };
 set_global("settings_notifications", _settings_notifications);
 
-const color_data = set_global("color_data", {});
+const color_data = {__esModule: true};
+rewiremock("../../static/js/color_data").with(color_data);
 set_global("current_msg_list", {});
 const message_util = set_global("message_util", {});
 const stream_color = set_global("stream_color", {});
@@ -35,6 +38,8 @@ set_global("message_list", {
 subs = set_global("subs", {update_settings_for_subscribed: noop});
 set_global("overlays", {streams_open: () => true});
 
+rewiremock.enable();
+
 const peer_data = zrequire("peer_data");
 const people = zrequire("people");
 const stream_data = zrequire("stream_data");
@@ -397,3 +402,4 @@ run_test("remove_deactivated_user_from_all_streams", () => {
     // verify that we issue a call to update subscriber count/list UI
     assert.equal(subs_stub.num_calls, 1);
 });
+rewiremock.disable();
diff --git a/frontend_tests/node_tests/ui_init.js b/frontend_tests/node_tests/ui_init.js
index 4feed0b72d..ebea603c7d 100644
--- a/frontend_tests/node_tests/ui_init.js
+++ b/frontend_tests/node_tests/ui_init.js
@@ -110,7 +110,6 @@ const util = zrequire("util");
 zrequire("hash_util");
 zrequire("stream_color");
 zrequire("stream_edit");
-zrequire("color_data");
 zrequire("stream_data");
 zrequire("condense");
 zrequire("lightbox");
diff --git a/static/js/archive.js b/static/js/archive.js
index 947dd2fe2f..85c20ea468 100644
--- a/static/js/archive.js
+++ b/static/js/archive.js
@@ -2,6 +2,8 @@ import _ from "lodash";
 
 import render_archive_message_group from "../templates/archive_message_group.hbs";
 
+import * as color_data from "./color_data";
+
 const {format, isSameDay} = require("date-fns");
 
 function should_separate_into_groups(current_msg_time, next_msg_time) {
diff --git a/static/js/bundles/app.js b/static/js/bundles/app.js
index 053a65c7d5..9fceb292c0 100644
--- a/static/js/bundles/app.js
+++ b/static/js/bundles/app.js
@@ -25,7 +25,6 @@ import "../message_list";
 import "../narrow";
 import "../reload";
 import "../compose_actions";
-import "../color_data";
 import "../stream_color";
 import "../stream_data";
 import "../stream_topic_history";
diff --git a/static/js/color_data.js b/static/js/color_data.js
index a0fa34125d..5ecc99d913 100644
--- a/static/js/color_data.js
+++ b/static/js/color_data.js
@@ -1,6 +1,6 @@
-"use strict";
+import _ from "lodash";
 
-const _ = require("lodash");
+export let unused_colors;
 // These colors are used now for streams.
 const stream_colors = [
     "#76ce90",
@@ -31,41 +31,39 @@ const stream_colors = [
 
 // Shuffle our colors on page load to prevent
 // bias toward "early" colors.
-exports.colors = _.shuffle(stream_colors);
+export const colors = _.shuffle(stream_colors);
 
-exports.reset = function () {
-    exports.unused_colors = exports.colors.slice();
-};
+export function reset() {
+    unused_colors = colors.slice();
+}
 
-exports.reset();
+reset();
 
-exports.claim_color = function (color) {
-    const i = exports.unused_colors.indexOf(color);
+export function claim_color(color) {
+    const i = unused_colors.indexOf(color);
 
     if (i < 0) {
         return;
     }
 
-    exports.unused_colors.splice(i, 1);
+    unused_colors.splice(i, 1);
 
-    if (exports.unused_colors.length === 0) {
-        exports.reset();
+    if (unused_colors.length === 0) {
+        reset();
     }
-};
+}
 
-exports.claim_colors = function (subs) {
+export function claim_colors(subs) {
     const colors = new Set(subs.map((sub) => sub.color));
     for (const color of colors) {
-        exports.claim_color(color);
+        claim_color(color);
     }
-};
+}
 
-exports.pick_color = function () {
-    const color = exports.unused_colors[0];
+export function pick_color() {
+    const color = unused_colors[0];
 
-    exports.claim_color(color);
+    claim_color(color);
 
     return color;
-};
-
-window.color_data = exports;
+}
diff --git a/static/js/global.d.ts b/static/js/global.d.ts
index ae321a903a..5254c14942 100644
--- a/static/js/global.d.ts
+++ b/static/js/global.d.ts
@@ -13,7 +13,6 @@ declare let bot_data: any;
 declare let buddy_data: any;
 declare let buddy_list: any;
 declare let click_handlers: any;
-declare let color_data: any;
 declare let compose_actions: any;
 declare let composebox_typeahead: any;
 declare let compose_ui: any;
diff --git a/static/js/stream_data.js b/static/js/stream_data.js
index 98ef48b97e..a742f5ccb6 100644
--- a/static/js/stream_data.js
+++ b/static/js/stream_data.js
@@ -1,5 +1,6 @@
 "use strict";
 
+const color_data = require("./color_data");
 const {FoldDict} = require("./fold_dict");
 const peer_data = require("./peer_data");
 const people = require("./people");
diff --git a/static/js/stream_events.js b/static/js/stream_events.js
index 6db9f7e882..0880f9d6ba 100644
--- a/static/js/stream_events.js
+++ b/static/js/stream_events.js
@@ -1,5 +1,6 @@
 "use strict";
 
+const color_data = require("./color_data");
 const narrow_state = require("./narrow_state");
 const peer_data = require("./peer_data");