Always use Symbol keys

--- name: classable-teleportability description: Skill for registering global singleton containers using Teleportability. Call this skill when setting up shared dependency containers, application bootstrapping, or cross-module singleton management. --- # Teleportability — Global Singleton Registry Always use Symbol keys

`Teleportability({ key, injects })` registers an Injectable at a global key on `globalThis` (default). Always use `Symbol.for("pkg:name")` to avoid key collisions across packages. String keys are error-prone in shared environments.

First-write-wins registration

The first `Teleportability()` call for a given key installs the container. Subsequent calls with the same key return the existing container. The `injects` from later calls are ignored. This is by design — declare all base dependencies in one place.

Late-binding with inject()

Use `Container.inject({ key: Class })` to push additional dependencies BEFORE the first `get()` or `instance` access. The Injectable constructor reads from the same mutable object, so late-bound tokens are visible at construction time. Calling `inject()` AFTER construction has no effect on existing instances.

Lazy construction

The container is not constructed until the first `get()` or `instance` access. This means `inject()` calls between registration and first access are all captured. After first access, the instances are cached.

Cleanup with dispose()

Call `Container.dispose()` to clear all cached instances and remove the registration from `globalThis`. The next `get()` call after dispose will re-construct everything. Essential for test isolation.

Correct: Application container with late-binding ./examples/correct-app-container.ts Correct: Real-world pattern from @ecosy/markdoc ./examples/correct-markdoc-pattern.ts Wrong: Common Teleportability mistakes ./examples/wrong-patterns.ts