diff --git a/packages/perspective/src/js/api/client.js b/packages/perspective/src/js/api/client.js
index 0f42ea760b..92df2db29f 100644
--- a/packages/perspective/src/js/api/client.js
+++ b/packages/perspective/src/js/api/client.js
@@ -20,114 +20,121 @@ import {bindall} from "../utils.js";
  *
  * @export
  */
-export function Client() {
-    this._worker = {
-        initialized: {value: false},
-        transferable: false,
-        msg_id: 0,
-        handlers: {},
-        messages: []
-    };
-    bindall(this);
-}
+export class Client {
+    constructor() {
+        this._initialized = false;
+        this._worker = {
+            initialized: {value: false},
+            transferable: false,
+            msg_id: 0,
+            handlers: {},
+            messages: []
+        };
+        bindall(this);
+    }
 
-/**
- * Remove a listener for a Perspective-generated event.
- */
-Client.prototype.unsubscribe = function(cmd, handler) {
-    for (let key of Object.keys(this._worker.handlers)) {
-        if (this._worker.handlers[key].resolve === handler) {
-            delete this._worker.handlers[key];
+    /**
+     * Remove a listener for a Perspective-generated event.
+     */
+    unsubscribe(cmd, handler) {
+        for (let key of Object.keys(this._worker.handlers)) {
+            if (this._worker.handlers[key].resolve === handler) {
+                delete this._worker.handlers[key];
+            }
         }
     }
-};
 
-/**
- * Process an asynchronous message.
- */
-Client.prototype.post = function(msg, resolve, reject, keep_alive = false) {
-    if (resolve || reject) {
-        this._worker.handlers[++this._worker.msg_id] = {resolve, reject, keep_alive};
-    }
-    msg.id = this._worker.msg_id;
-    if (this._worker.initialized.value) {
-        this.send(msg);
-    } else {
-        this._worker.messages.push(() => this.send(msg));
+    /**
+     * Process an asynchronous message.
+     */
+    post(msg, resolve, reject, keep_alive = false) {
+        if (resolve || reject) {
+            this._worker.handlers[++this._worker.msg_id] = {resolve, reject, keep_alive};
+        }
+        msg.id = this._worker.msg_id;
+        if (this._worker.initialized.value) {
+            this.send(msg);
+        } else {
+            this._worker.messages.push(() => this.send(msg));
+        }
     }
-};
 
-Client.prototype.initialize_profile_thread = function() {
-    if (this._worker.initialized.value) {
-        this.send({id: -1, cmd: "init_profile_thread"});
-    } else {
-        this._worker.messages.push(() => this.send({id: -1, cmd: "init_profile_thread"}));
+    initialize_profile_thread() {
+        if (this._worker.initialized.value) {
+            this.send({id: -1, cmd: "init_profile_thread"});
+        } else {
+            this._worker.messages.push(() => this.send({id: -1, cmd: "init_profile_thread"}));
+        }
     }
-};
 
-/**
- * Must be implemented in order to transport commands to the server.
- */
-Client.prototype.send = function() {
-    throw new Error("send() not implemented");
-};
-
-Client.prototype.open_table = function(name) {
-    return new proxy_table(this, name);
-};
+    /**
+     * Must be implemented in order to transport commands to the server.
+     */
+    send() {
+        throw new Error("send() not implemented");
+    }
 
-Client.prototype.open_view = function(name) {
-    return new proxy_view(this, name);
-};
+    /**
+     * Given the name of a table that is hosted on the server (e.g. using `perspective-python` or `perspective` in NodeJS),
+     * return a `table` instance that sends all operations and instructions to the `table` on the server.
+     *
+     * @param {string} name
+     */
+    open_table(name) {
+        return new proxy_table(this, name);
+    }
 
-let _initialized = false;
+    open_view(name) {
+        return new proxy_view(this, name);
+    }
 
-/**
- * Handle a command from Perspective. If the Client is not initialized, initialize it and dispatch the `perspective-ready` event.
- *
- * Otherwise, reject or resolve the incoming command.
- */
-Client.prototype._handle = function(e) {
-    if (!this._worker.initialized.value) {
-        if (!_initialized && typeof document !== "undefined") {
-            var event = document.createEvent("Event");
-            event.initEvent("perspective-ready", false, true);
-            window.dispatchEvent(event);
-            _initialized = true;
-        }
+    /**
+     * Handle a command from Perspective. If the Client is not initialized, initialize it and dispatch the `perspective-ready` event.
+     *
+     * Otherwise, reject or resolve the incoming command.
+     */
+    _handle(e) {
+        if (!this._worker.initialized.value) {
+            if (!this._initialized && typeof document !== "undefined") {
+                var event = document.createEvent("Event");
+                event.initEvent("perspective-ready", false, true);
+                window.dispatchEvent(event);
+                this._initialized = true;
+            }
 
-        const msgs = this._worker.messages;
-        this._worker.initialized.value = true;
-        this._worker.messages = [];
+            const msgs = this._worker.messages;
+            this._worker.initialized.value = true;
+            this._worker.messages = [];
 
-        if (msgs) {
-            for (const m in msgs) {
-                if (msgs.hasOwnProperty(m)) {
-                    msgs[m]();
+            if (msgs) {
+                for (const m in msgs) {
+                    if (msgs.hasOwnProperty(m)) {
+                        msgs[m]();
+                    }
                 }
             }
         }
-    }
-    if (e.data.id) {
-        var handler = this._worker.handlers[e.data.id];
-        if (handler) {
-            if (e.data.error) {
-                handler.reject(e.data.error);
-            } else {
-                handler.resolve(e.data.data);
-            }
-            if (!handler.keep_alive) {
-                delete this._worker.handlers[e.data.id];
+        if (e.data.id) {
+            var handler = this._worker.handlers[e.data.id];
+            if (handler) {
+                if (e.data.error) {
+                    handler.reject(e.data.error);
+                } else {
+                    handler.resolve(e.data.data);
+                }
+                if (!handler.keep_alive) {
+                    delete this._worker.handlers[e.data.id];
+                }
             }
         }
     }
-};
 
-Client.prototype.table = function(data, options) {
-    return new table(this, data, options || {});
-};
+    table(data, options) {
+        return new table(this, data, options || {});
+    }
 
-Client.prototype.terminate = function() {
-    this._worker.terminate();
-    this._worker = undefined;
-};
+    terminate() {
+        this._worker.terminate();
+        this._worker = undefined;
+    }
+}