# CrewOS external-participant capability — build trace (sanitized)

_Source: CrewOS plan history, the Cast Run 61 root-refresh operating record, and the post-execution
attestation. Client-identifying data redacted (see the package manifest). Commit identifiers shown are
the ones the technical companion (§11) already publishes, plus the lifecycle-halt commit._

The external-participant capability work is the strongest current end-to-end build example. It moved a
real capability through planning, durable execution, parallel construction, explicit integration, a
source-identity halt, separate post-execution audit, documentation refresh, and follow-on
running-system verification.

```text
Business capability (external-participant portal — un-designation)
→ approved plan
→ durable planned execution on Chassis
→ parallel CrewOS worktrees
→ explicit integration
→ source-ambiguity HALT  (audit refused an ambiguous checkout — see source-ambiguity-halt.md)
→ corrected source conditions
→ post-execution audit → CLEAN  (see clean-attestation.md)
→ documentation refresh (Caster root-refresh, Cast Run 61)
→ follow-on Cure verification on the deployed surface (see epp-clear-path-finding.md)
```

## Scale

- **146 commits across multiple worktrees.** This figure is **attributed to the Cast Run 61 operating
  record** (`system/caster/runs/cast-run-61-2026-07-25/root-refresh.md`, "146 commits (EPP substrate)"
  / "146 commits via multiple worktrees"). It is *not* presented as a count reconstructable from a
  single git range — the work spanned multiple worktrees and branches with no single boundary pair, and
  a different branch-counter window in the same record reports a different number for a different span.

## Commit trace (published identifiers)

| Stage | Commit | What it is |
| --- | --- | --- |
| Un-designation merge | `d20a60ea` | Ships the missing *clear* path for a durable participant designation (see the finding artifact). |
| Lifecycle halt | `0eb96a25c` | The post-exec audit halted on an ambiguous checkout rather than issuing a verdict. |
| CLEAN attestation | `93255817` | Authoritative CLEAN post-exec attestation, cycle 1, 0 findings. |

## What this trace establishes

A substantial build crossed planning, durable execution, parallel construction, integration, audit,
maintenance, and running-system verification — **including a deliberate halt when source identity could
not support a trustworthy verdict.** It does not establish that FoundryOS can autonomously deliver every
application; it is one exercised, audited, verified capability build.