Source model

Canonical source

The source of truth is the fragment tree under archledger_dir:

• sections/ for the major arc42 chapter skeleton

• records/ for individual architecture facts

• archive/ for archived records and tombstones that preserve allocated ledger IDs

Records include structural, behavioral, and decision artifacts plus first-class diagram records. Diagram records default to plain text diagrams (diagram_type = "text"). Text diagrams stay embedded in Markdown/AsciiDoc record bodies as readable fenced blocks. Mermaid is available for compact sequence, state, or flow diagrams but is not the default.

Fragments contain YAML front matter and a body in the configured dialect. Archived fragments keep normal front matter and use status: archived.

Ledger ID format

Default IDs use <prefix>_<number> (for example al_0013).

When [ids].segment_mode = "type", IDs use <prefix>_<segment>_<number> (for example al_content_0013 and al_risk_0014). Segment values come from metadata/config mapping, while the numeric sequence remains one global ledger-wide counter.

Traceability

Use source_refs when fragments describe real files or directories. Directory refs must end with / and must exist in the workspace.

Generated output

Generated build outputs are derived artifacts and should not be edited as source. New projects default to build/ under the workspace root, and [build].default_output_dir may place outputs elsewhere.