diff --git a/.eslintignore b/.eslintignore
index b126955..4ced8a0 100644
--- a/.eslintignore
+++ b/.eslintignore
@@ -1,2 +1,3 @@
 testpilot-metrics.js
 lib/shield/*.js
+lib/testpilot/*.js
diff --git a/lib/testpilot/experiment.js b/lib/testpilot/experiment.js
new file mode 100644
index 0000000..329bd69
--- /dev/null
+++ b/lib/testpilot/experiment.js
@@ -0,0 +1,102 @@
+const { AddonManager } = require('resource://gre/modules/AddonManager.jsm');
+const { ClientID } = require('resource://gre/modules/ClientID.jsm');
+const Events = require('sdk/system/events');
+const { Services } = require('resource://gre/modules/Services.jsm');
+const { storage } = require('sdk/simple-storage');
+const {
+  TelemetryController
+} = require('resource://gre/modules/TelemetryController.jsm');
+const { Request } = require('sdk/request');
+
+
+const EVENT_SEND_METRIC = 'testpilot::send-metric';
+const startTime = (Services.startup.getStartupInfo().process);
+
+function makeTimestamp(timestamp) {
+  return Math.round((timestamp - startTime) / 1000);
+}
+
+function experimentPing(event) {
+  const timestamp = new Date();
+  const { subject, data } = event;
+  let parsed;
+  try {
+    parsed = JSON.parse(data);
+  } catch (err) {
+    // eslint-disable-next-line no-console
+    return console.error(`Dropping bad metrics packet: ${err}`);
+  }
+
+  AddonManager.getAddonByID(subject, addon => {
+    const payload = {
+      test: subject,
+      version: addon.version,
+      timestamp: makeTimestamp(timestamp),
+      variants: storage.experimentVariants &&
+        subject in storage.experimentVariants
+        ? storage.experimentVariants[subject]
+        : null,
+      payload: parsed
+    };
+    TelemetryController.submitExternalPing('testpilottest', payload, {
+      addClientId: true,
+      addEnvironment: true
+    });
+
+    // TODO: DRY up this ping centre code here and in lib/Telemetry.
+    const pcPing = TelemetryController.getCurrentPingData();
+    pcPing.type = 'testpilot';
+    pcPing.payload = payload;
+    const pcPayload = {
+      // 'method' is used by testpilot-metrics library.
+      // 'event' was used before that library existed.
+      event_type: parsed.event || parsed.method,
+      client_time: makeTimestamp(parsed.timestamp || timestamp),
+      addon_id: subject,
+      addon_version: addon.version,
+      firefox_version: pcPing.environment.build.version,
+      os_name: pcPing.environment.system.os.name,
+      os_version: pcPing.environment.system.os.version,
+      locale: pcPing.environment.settings.locale,
+      // Note: these two keys are normally inserted by the ping-centre client.
+      client_id: ClientID.getCachedClientID(),
+      topic: 'testpilot'
+    };
+    // Add any other extra top-level keys = require(the payload, possibly including
+    // 'object' or 'category', among others.
+    Object.keys(parsed).forEach(f => {
+      // Ignore the keys we've already added to `pcPayload`.
+      const ignored = ['event', 'method', 'timestamp'];
+      if (!ignored.includes(f)) {
+        pcPayload[f] = parsed[f];
+      }
+    });
+
+    const req = new Request({
+      url: 'https://tiles.services.mozilla.com/v3/links/ping-centre',
+      contentType: 'application/json',
+      content: JSON.stringify(pcPayload)
+    });
+    req.post();
+  });
+}
+
+function Experiment() {
+  Events.on(EVENT_SEND_METRIC, experimentPing);
+}
+
+Experiment.prototype = {
+  constructor: function() {
+    Events.on(EVENT_SEND_METRIC, experimentPing);
+  },
+
+  ping: function(event) {
+    experimentPing(event);
+  },
+
+  teardown: function() {
+    Events.off(EVENT_SEND_METRIC, experimentPing);
+  }
+};
+
+module.exports = Experiment;
diff --git a/testpilot-metrics.js b/testpilot-metrics.js
index f68aae3..2aad4bd 100644
--- a/testpilot-metrics.js
+++ b/testpilot-metrics.js
@@ -1,6 +1,9 @@
 // This Source Code Form is subject to the terms of the Mozilla Public
 // License, v. 2.0. If a copy of the MPL was not distributed with this
 // file, You can obtain one at http://mozilla.org/MPL/2.0/.
+const Experiment = require('./lib/testpilot/experiment');
+
+const experiment = new Experiment();
 
 /**
  * Class that represents a metrics event broker. Events are sent to Google
@@ -170,6 +173,7 @@ Metrics.prototype = {
       };
 
       try {
+        console.log("notifying observerser of testpilot::send-metric; subject: ", subject, " stringified: ", stringified);
         Services.obs.notifyObservers(subject, 'testpilot::send-metric', stringified);
         this._log(`Sent client message via nsIObserverService: ${stringified}`);
       } catch (ex) {