Hey Joyce Builds In-House Webinar System with AWS IVS and Sendbird

Hey Joyce, the working women's community run by Kurly subsidiary Planery, built its own webinar system to overcome the limitations of offline networking following COVID-19. The team decided to develop it in-house to solve problems that arose from using external solutions—degraded user experience, excessive operational resources, and the inability to collect data.

Tech Stack and Architecture

To maximize efficiency for a very small team, the development team adopted a serverless architecture centered on AWS IVS and Sendbird. Live streaming was implemented using AWS IVS's ivs SDK and Video.js, while real-time chat leveraged Sendbird's Open Channel feature to support a large number of simultaneous connections. Data processing was designed with an MSA (microservices architecture) structure based on GraphQL and DynamoDB.

Key Development Issues and Solutions

The initial MVP was completed in just 2 weeks and launched in August 2020, and has since handled more than 200 talks. During development, the team resolved two major technical challenges.

• Handling Autoplay Policies: To reduce user confusion caused by browser autoplay restrictions (such as Chrome's mandatory muting), the team applied a UX that displays the time remaining before the webinar starts and shows a mute notification message after it begins.
• Overcoming DynamoDB Capacity Limits: To solve the problem where the 400KB maximum size limit per Item made it impossible to store data for 1,000+ attendees, the team carried out a schema change that separated webinar information and attendee data into separate tables.

Operational Results

Adopting the in-house system enabled real-time responsiveness through separated tabs for announcements, speakers, and chat, and opening free webinars lowered the barrier to registration and increased participation rates. In addition, the team used AWS Batch and EventBridge to automate attendee list generation and notification sending, securing operational efficiency.