meteor-blaze: jQuery is a hard runtime requirement up to Blaze 3.0.3 and optional from 3.1.0-alpha.0 (prerelease), and the skill never mentions it

[dupontbertrand]

Problem encountered while developing an application. This issue was written and opened by Claude Code, after review by the author.

Heads-up: meteor-blaze never mentions jQuery, and its "Current scaffold" package list omits it, while meteor create --blaze on Meteor 3.5.1 adds the jquery Meteor package and the jquery npm dependency. The dependency is a hard runtime requirement up to Blaze 3.0.3 and becomes optional from blaze@3.1.0-alpha.0. This is a version boundary in the sense of AGENTS.md (Versioning: "Independently released Atmosphere and npm packages use their package version, not the Meteor release, as the capability floor", and "Add case coverage for both the supported version and an earlier-version near miss when a skill spans the capability boundary"), and it is missing.

Blaze 3.0.3 (what the scaffold resolves today)

meteor remove jquery plus meteor npm uninstall jquery on an app that never calls $() directly: the client dies at boot.

Error: jQuery not found                      (packages/blaze.js)
TypeError: Cannot read properties of undefined (reading 'Blaze')   (app/global-imports.js)
ReferenceError: meteorInstall is not defined
TypeError: require is not a function         (__rspack__/client-rspack.js)

Only the first line is the cause; the three others are the cascade the console shows next.

blaze@3.1.0-alpha.0 (Atmosphere, June 2026, meteor/blaze#493 dual DOM backend)

Same app, blaze-html-templates@3.1.0-alpha.0 and blaze@3.1.0-alpha.0 pinned, jQuery removed: the app boots, Blaze._DOMBackend._hasJQuery === false, subscriptions and events work. When jQuery is still present, the alpha logs at boot:

[Blaze] jQuery 3.7.1 detected as DOM backend. Native DOM backend is available — remove jquery to enable native DOM backend. jQuery support will be removed in Blaze 4.0.

A second line follows it, [Blaze] jQuery was loaded via <global scope|Meteor packages>. That pair is the verification marker: present while jQuery is loaded, gone once removal succeeded. Removal order that works: upgrade Meteor, pin the alpha, then remove jquery (Meteor package and npm). Removing first reproduces the 3.0.3 crash.

Known limitation of the prerelease: meteor/blaze#512 (delegated event selector scope in native mode), fix meteor/blaze#513 still open. HISTORY.md has no 3.1.0 entry and the repository has no tag for it yet, so the published Atmosphere version (blaze@3.1.0-alpha.0, 25 June 2026) and PR #493 are the only version evidence for now.

Suggested change

• List jquery in the scaffold package list and state the 3.0.x requirement.
• Add the 3.1.0-alpha.0 boundary with the marker and the order above, flagged as prerelease.
• Two eval cases: an app on Blaze 3.0.3 asking to remove jQuery (pass if the agent refuses and proposes the upgrade first); an app pinned on the alpha asking the same (pass if the agent gives the order and checks the console marker).