prometeu-studio/discussion/lessons/DSC-0003-packer-docs-import/LSN-0009-mental-model-packer-legacy.md

id	ticket	title	created	tags
LSN-0009	packer-docs-import	Packer mental model legacy lesson	2026-03-26	packer legacy-import mental-model

Context

Legacy import from docs/packer/learn/mental-model-packer.md.

This lesson preserves the high-level didactic framing of what the packer is and is not.

Key Decisions

The packer turns asset workspaces into stable asset artifacts

What: The packer is neither cartridge shipper, runtime reader, nor generic file janitor. It is the system that turns a managed asset workspace into stable runtime-facing and tool-facing artifacts. Why: Contributors drift quickly when they treat packer behavior as a mix of authoring convenience, runtime semantics, and shipping responsibilities rather than one explicit artifact-producing domain. Trade-offs: This framing forces sharper boundaries between packer, runtime, shipper, and Studio, but it keeps contracts and responsibilities legible.

Patterns and Algorithms

• Treat the managed asset root as the unit of management.
• Split source-of-truth responsibilities between registry state and per-asset declaration.
• Keep asset_id and asset_name as separate concepts.
• Treat assets.pa as the authoritative runtime-facing artifact.
• Prefer determinism, explicit declaration, and canonical serialization.

Pitfalls

• Treating the packer like a generic filesystem janitor.
• Collapsing asset_id and asset_name into one concept.
• Forgetting that determinism is part of the artifact contract chain.

Takeaways

• The packer owns artifact production, not runtime reading or shipping.
• Stable asset identity and deterministic output are central to the whole domain.
• Legacy source attribution: docs/packer/learn/mental-model-packer.md.