Engineering notes

Umbraco 13.0.0-13.12.0 got a moderate security patch on 9 December. Everything else the month produced came from 24 Days in Umbraco, plus a new Enterprise bundle and a Q1 2026 date for Compose.

The new Content Hub import/export engine is now the default and existing CI/CD pipelines break. Everything else in December was the community explaining SitecoreAI, Blok, Connect and App Router without a single post from sitecore.com.

Umbraco 17 LTS landed on 27 November on .NET 10, with three years of support. uSync 17.0.0 and Clean Starter Kit v7 shipped the same day. The community had a harder month than the product did.

Symposium folded XM Cloud, CDP, Personalize, Search and Content Hub into SitecoreAI. 106 items harvested, 14 cited, zero published by the vendor. What is confirmed, what is second-hand, and what to check before signing.

Umbraco 17 shipped as a beta on 15 October with the final set for 27 November, and uSync 16.1.0 was declared the last feature release for v16. What that costs a site still on 13.

A YAML error that writes a 0 KB resource package and still returns success, the JSS to Content SDK decision, and an agentic product surface explained by practitioners instead of by Sitecore.

Umbraco's September 2025: a security patch for Umbraco 13 through the Smidge dependency, the Developer MCP Server beta moving into Umbraco's own namespace, two uSync patches, and the 2026 price list read after the fact.

Content SDK 1.1 landed and the Experience Editor did not come with it. Every account of that migration in our September 2025 harvest came from a personal blog, not from a vendor page.