v0.28.0

Breaking changes

• Rails 7.2 is no longer supported: Proscenium now requires Rails 8.0 or later. Rails 7.2's security support ended on 9 August 2026. An app on 7.2 stays on Proscenium 0.27 until it upgrades Rails. Nothing else changes for apps already on Rails 8.

Fixes

Security

• The compiled library now builds with Go 1.27.3. Published gems carried Go 1.27.1's standard library, without the security fixes in Go 1.27.2 and 1.27.3. govulncheck found nine of those advisories reachable from Proscenium's code, mainly through the request that fetches an SVG imported from a remote URL. Updating the gem is all an app needs to do.

Puma

• A Puma worker gives back its idle Go threads. Go never ends a thread by itself, so a worker that had used the library kept about GOMAXPROCS idle threads for life, and on a large machine those could exhaust a container's task limit. They now end 30 seconds after the library was last used.

CLI

• proscenium install no longer repeats its .gitignore lines before a root-anchored rule. A rule such as /.dev-docs after those lines counted as hiding the contexts, so every install appended the lines again.