Platform Evolution
Assessment run-2026-07-27-1 · 213 of 213 repos assessed

Data stores

Every data technology the estate runs on, not just the shared SQL estate: MongoDB carries a large share of the cloud services, Redis is a second coupling plane, and DynamoDB and S3 underpin the payments and document platforms. Repos sharing a store are coupled even without a code edge. The three core SQL databases are binding points; stage 4 of the programme gives them named owners.

Repos using each technology

A repo can use several technologies. Click a bar to filter the stores below.

The shape of the data estate

SQL Server: 98 stores across 89 repos. The legacy centre of gravity, and where the shared-schema coupling lives.

MongoDB: 75 stores across 66 repos. The default operational store for the modern and cloud services, mostly one database per service, which is exactly the decoupled pattern the programme wants.

Redis: 11 stores across 46 repos. Caching, session state and streams; shared instances couple services as a second plane.

Amazon S3: 13 stores across 12 repos. Object storage for documents, assets and request logs.

DynamoDB: 8 stores across 6 repos. The payments platform's serverless store.

Azure Blob Storage: 1 store across 1 repo.

OpenSearch: 1 store across 1 repo.

Snowflake: 1 store across 1 repo.

Shared stores (2) — Amazon S3

StoreTechnologyCoupled repos
s3:mail-message-data Amazon S32tc-mail-composer, tc-mail-orchestrator
s3:Public_BlogVideos Amazon S32asset-management, tc-public-assets-api

Single-owner stores (11) — Amazon S3

Owned by one repo each; no cross-system coupling. This is the healthy pattern most of the MongoDB estate follows.

s3:CX_MailClaimCheckS3s3:dmc-ai-pocs3:document-definition-claim-check-buckets3:document-storages3:pcipal-api-prod-request-response-logss3:Public_Assetss3:Public_DocumentationBuckets3:Public_TcCalendars3:stripe-api-prod-request-response-logss3:tc-costsavings-api-prod-request-response-logss3:VibeBookingBucket