# Rebuildable Projection **Domain:** Data Architecture / Derived Systems **Doc Type:** Canonical Concept Node **Maturity:** Core Design Principle **Related:** [[wiki/Filesystem as Source of Truth|Filesystem as Source of Truth]], [[wiki/Derived Artifact|Derived Artifact]], [[wiki/Deterministic Transformation|Deterministic Transformation]] --- ## Definition **A rebuildable projection is a derived representation that can be regenerated from a more authoritative source.** Examples include search indexes, route tables, SQLite read models, static pages, feed records, posters, combined bundles, and cache files. ## Project Context The principle allows fast or channel-specific forms without surrendering canonical ownership. A folder-and-Markdown corpus may produce a database for speed; modular Shazam sources may produce one combined file; an essay may produce dozens of landing pages and posters. ## Key Insight **Derived speed and convenience are safe when regeneration is deterministic and the source remains intact.** ## See Also [[wiki/Generated Packaging|Generated Packaging]], [[wiki/Offline Precomputation|Offline Precomputation]], [[wiki/Normalized Output|Normalized Output]], [[wiki/Technical Terms|Technical Terms]]