MailChimp Calendar Invite Marketing
A Review of how Calendar Invites are inserted into MailChimp and Updated for Calendar Invite Marketing Offers
Intro to CIM
The Killer App goal has been to define a new category called Calendar Invite Marketing. (CIM).
The tech stack used is the Calendarsnack Front End + AWS Calendar Invite Server Back End + API’s.
This specific series is for Embedding the Calendar Invite into Email Marketing templates.
In this review, we will follow the slides of a recent post and YouTube videos for the AWS Calendar Invite Server for Summer 2025 with a focus on the MailChimp RSVP button.
The 2025 MLB data is used in the AWS Calendar Invite server for Live demos to explain how the stack works.
MLB Data
The AWS Calendar Invite Server stack is installed in an AWS account and set up with a domain and AWS SES account to meet calendar invite sending compliance and security requirements of any Marketing Agency, OEM, or enterprise company model that wants to use the Embedded Calendar Invite API Button.
The Calendar Invite processing workflows are well defined in the High Level Design in this Github repo for more info.
Using the Calendar Client as Create, Read, Update and Delete (CRUD) to the AWS Calendar Invite Server
Ingest into AWS Calendar Invite Server
In this example, the organizer sends the MLB Calendar Invite for the MLB Game Angels VS Rangers for July 30th to the create@calendarsnack.com email box from a Google Calendar Client.
The configured AWS Simple Email Service Box serves as the starting point for processing the organizers' events via the Calendar Invite drop-off.
In this demo app, it is create@calendarsnack.com for drop-off processing.
Several Lambdas collect, disassemble, and store the calendar invite data in the storage layer for various Calendar Invite Sending for Marketing and Transactional Use Cases with API#1.
API#1 - Sending on the AWS Calendar Invite Server
API #1 End Point matches the UID data pulled from the storage layer, assembles and sends out a custom-crafted calendar Invite for that event, with a Calendar Receipt requested.
Data Ingest Tags for CRUD
Data is ingested from the Organizer's Calendar Client for three possible tags in the database using the AWS Calendar Invite Server Stack.
They are New, Updated, or Canceled.
These tags determine the workflow of the reconstructed Calendar Invite with the AWS Calendar Invite Server Endpoint for matching the email address to the UID status of New, Update, or Cancel sending.
Whenever the Organizer updates the data in the Calendar Client, we log this change for the registered user of the AWS Calendar Invite Server communicating with the Simple Email Service Box. (SES).
AWS Calendar Invite Server Workflow Options
Scheduled or Auto-Sending of Calendar Invites
There is a software switch for determining whether to send Calendar Invites automatically or approve and schedule their sending on the AWS Calendar Invite Server Stack. This demo has the Auto Sending on.
Any of these three options results in a Calendar Invite being sent with the AWS Calendar Invite Server API #1 when the Endpoint is specified.
Before we send, let's explore the Calendar Invite Marketing (CIM) solution workflow for MailChimp.
This MailChimp use case involves embedding the Calendar Invite Sending into the Call to Action Button within a MailChimp campaign, utilizing the API to match the Event's UID with MailChimp's Database email address.
Once the AWS Calendar Invite Server sends the Calendar Invite, the Organizer of the Calendar Client can update the Offer to experiment with timing and promotional offers inside the Message Body by pushing them back to the Ingest Process.
The MailChimp RSVP with a Calendar Invite Embed
High-Level Design.
Matching the MailChimp Email Address from the MailChimp template to the Calendar Invite UID.
The MailChimp CTA Button gets an embedded Calendar Invite API code.
When the MailChimp User Clicks the RSVP button, the calendar invite is sent from the AWS Calendar Invite Server for the MLB Game, and calendar receipts are requested to track customer intentions.
In the initial Calendar Invite, the message body does not include an offer in this demo example.
In this example, you could start the Offer in the First Calendar Invite and then step through the promotion offers using the Calendar Invite Updates as we did here.
Other Examples-
Reduced Ticket Prices before specific dates. Special Merchandise for this Game. Come by my Booth while at the game. Using the Calendar Invite Update Function to push the data to the AWS Calendar Invite Server and then have them sent out either automatically or with an approval workflow.
Calendar Invite Marketing (CIM) Scenarios
MailChimp Calendar Invite Message Update 1
The first Update is completed using the Calendar Client's Edit and Save function.
The Organizer returns to the Calendar Client used for the Event, opens it, makes the change, saves it, and then resends the calendar invite data to create@calendarsnack.com.
The data is reprocessed and stored for the UID.
In Update 1, the Organizer Inserts "Come by 675 and have a beer on us by the 5th inning" into the message body and then saves the Calendar Client Invite for the Angels vs. Texas Game on July 30th.
This is a TYPO. It should say "Come by the Booth 675 and have a beer on us by the 5th inning".
So that is what we do in UPDATE #2.
MailChimp Calendar Invite Message Update 2
In Update 2, we type in the Message body, "Come by the Booth 675 and have a beer on us by the 5th inning," and fix the typo.
We also save the Calendar Client data for the Angels vs. Rangers game on July 30th pushing the new data to the AWS Calendar Invite Server to be processed.
In the last Update # 3, we updated the message body to extend the Inning giveaway from Inning 5 to Inning 9 for the Free Beer Offer.
MailChimp Calendar Invite Message Update 3
In Update 3, we've added to the message body: "Come by the Booth 675 and have a beer on us by the 9th inning."
Changed from 5th to 9th Inning.
Save the Calendar Client information and update the Database for the third time.
The API then shuffles the new data to the Application APIs when called.
The 3 Updates for MailChimp Calendar Invite Offer
This workflow highlights high Client to Server Updates, pushing data through the AWS Calendar Invite Server to create a Calendar Invite Marketing Workflow.
This option enhances your Email Marketing Campaign by utilizing Calendar Invite Offers within the MailChimp technology stack.
Tracking the Calendar Client to Server EVENT UID
This slide shows EventID: s9409losjlc9qm7p89rbkairpono11h3a3m7ug81 and its tracking history in the console for each Update from the Client to the Server.
AWS Calendar Invite Server RSVP Receipts
This slide shows EventID: s9409losjlc9qm7p89rbkairpono11h3a3m7ug81 and its tracking history in the console for each Update from the Client to the Server.
The AWS Calendar Invite Server requests a Calendar receipt each time API#1 sends a customer calendar invite for that UID.
The Server collects and stores Calendar Receipt data for API calls and Analytics, which is then used in the Calendar Invite reporting Dashboards.
The Calendar Receipts are called back using the NEEDS action Role for each Calendar Invite Sent out and matched to the MailChimp Email Address.
We utilize Lambdas, S3, and DynamoDB as part of our data parsing stack to track all UID-related data for Calendar Receipts.
When a customer changes their calendar invite status to Y, N, or M, we update the data in the AWS Calendar Invite Server, allowing us to collect RSVP intents to measure offers and communicate directly to the calendar.
How the MailChimp RSVP Code Inserts works
Copy Code for Specific Event
MailChimp Calendar Invite Workflow for Customer
MailChimp Customer POV
MailChimp RSVP Button Landing Page Redirect with streaming Events
This page calls all Upcoming Event data from the AWS Calendar Invite Server stored under the Organizer for future events and streams them to this page for 1 Click Calendar Invite Sending with API#1 Embedded.
This is optional but we believe the best practice for Calendar Invite Marketing.
The Tech Stack Vids and Docs
Tube
https://www.youtube.com/@calendarinvite/videos
Github Docs
https://github.com/calendarinvite/calendarinviteserver
greg@31events.com