Install and pin

Install the packages your code imports, each by the name its API page shows, beside the remix your app already uses:

npm add @sdxc/markdown @sdxc/result remix

Every guide opens with the install line for the packages its code imports. A package that runs inside a Remix app lists remix as a peer: your app installs it once, and every package reads that same copy. A bundle carries only the subpaths it imports, such as @sdxc/markdown/html.

The version you get looks like a date, because it is one: a release is named for the day it was published. Write that date into your manifest exactly rather than as a range — Versioning covers the scheme and what an exact pin buys you.

Keep every package on one date

When a package installs a sibling from this collection, that dependency is pinned exactly too, at the version it was built and tested with. This is also why a release day tends to publish more than the packages that changed: a dependent republishes so its pin can move.

So pin every @sdxc package in a project to the same date and move them together. Mixed dates duplicate a shared dependency: @sdxc/spec@2026.9.4 beside @sdxc/jwt@2026.9.1 yields two copies of @sdxc/duration when their pins differ, and their context keys and instanceof checks stop matching between the copies. Moving both to the same day collapses them.

{
	"dependencies": {
		"@sdxc/markdown": "2026.9.21",
		"@sdxc/result": "2026.9.21",
		"remix": "3.0.0"
	}
}

Three packages run at build or test time: @sdxc/cloudflare-mocks, @sdxc/jsdoc and @sdxc/spec. Install them as dev dependencies, on the same date as the rest.

The sdxc command, installed globally from @sdxc/kit, starts a project from a template and writes controllers, jobs and models where the app layout puts them. The sdxc command covers it.

Finding out what changed

There are no changelog files. The day's release is recorded as a git tag, v2026.9.4, and a GitHub Release whose notes are the commits that went into it, with a compare link to the previous release. That is the whole record, and it is the thing to read before a pin moves.