MyMahi, a New Zealand-based digital education company, built their student platform using CockroachDB Core embedded in a technology stack that includes spot instances (e.g., AWS Fargate), serverless functions (e.g., AWS Lambda), and GraphQL (e.g., GraphQL.js, GraphQL Tools). They chose the open source version of CockroachDB as their database because it met their requirements for scalability, ACID transactions, and ease of use. MyMahi's application architecture includes components such as Route53 DNS resolution, Cloudfront CDN, API Gateway, Lambda, SQS queue, S3 bucket, and a CockroachDB cluster. They use AWS Fargate spot instances to lower costs for their database cluster and handle bursts of traffic using AWS Lambda with Node.js. MyMahi also uses GraphQL to fetch exact data from CockroachDB and has abstracted transaction retry logic into a single function.