How it was built / operating model
Built with agents.
Shipped with evidence.
Hologram is a browser-based parametric CAD and simulation environment for mechatronics. The browser apps and the agent-facing server call the same geometry, physics, and export logic.
The deeper engineering artifact is the control system around parallel work: isolated branches, declared file ownership, hermetic proof, review-gated integration, and an explicit record of what was not verified.
01 / the operating model
Parallelism without shared-file roulette.
The system removes collisions before work starts. A round declares bounded lanes and checks their manifests against every concurrent branch.
Plan the collision out.
The round document names each lane, its exact file manifest, and the paths it must not touch before an agent begins.
Make ownership legible.
One slug connects the wt/<slug> branch, worktree directory, board owner, commit author, and sprint log.
Prove it in isolation.
Lane tests forbid network dependence, avoid a live app or agent session, and report failure through process.exitCode.
Integrate through review.
A lane commits only its own branch. Review and the owner control the merge; real-app verification remains a separate completion gate.
02 / one rulebook, mixed engines
Different vendors. One standard.
Round 9 deliberately planned six lanes across four Claude seats, one Codex seat, and one Gemini 3.1 Pro seat. Every seat inherited the same branch, manifest, test, authorship, and logging rules.
Round 9B added four small lanes using spare capacity. Their manifests were checked against all six Round 9 lanes, all seven reviewed-but-unmerged Round 10 branches, and one another.
The review record is more useful than the staffing plan. Two assignments changed vendors in the terminal and were disclosed under the actual model identity. Nine lanes ran and were approved; one planned lane is recorded as not run.
03 / evidence is interface
Inspectable beats impressive.
Every factual statement and number on this page carries a data-cite path to a source file in the repository.
Claim annotation
data-cite="docs/AGENT-WORKFLOW.md"
Hermetic by construction
New lane tests stub global.fetch to throw and cannot depend on a live development server, browser, or agent process.
Regression before confidence
Touched JavaScript is syntax-checked, then the full existing test suite runs—not only the new test that motivated the change.
Logs name the boundary
Each sprint log separates verified behavior from assumptions, records judgement calls, and leaves blocked checks open.
A green suite is evidence, not proof
Real-app verification with zero console errors remains part of “done”; an unattended lane cannot silently substitute a unit test for it.
04 / the artifact
Not a demo of agents. A CAD system they must answer to.
Hologram connects parametric design, mechanisms, physics, control, and fabrication export in one browser-based workflow. The operating model exists to make that product safer to extend in parallel.