Schematex
pert·PMI PMBOK 7 (critical path) + Gantt 1910·construction, engineering·complexity 3/3·since v0.6.0

Construction schedule (Gantt, computed critical path)

A residential construction Gantt on a continuous calendar — excavation through handover. The engine computes the critical path (excavation → foundation → framing → electrical → drywall → finishes → handover) and shows the float on the parallel roofing and plumbing trades.

For the site planner sequencing trades

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gantt·§ —
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Gantt chart — Residential Build Gantt chart: 9 tasks, project duration 50d. Starts 2026-09-01 (continuous). Critical path: EXC → FND → FRM → ELEC → DRY → FIN → HAND. Residential Build Sep 1 Sep 8 Sep 15 Sep 22 Sep 29 Oct 6 Oct 13 Oct 20 Excavation Foundation Framing Roofing Electrical Plumbing Drywall Finishes Handover 6d 8d 12d 6d · slack 2 8d 7d · slack 1 6d 10d 9 tasks · duration 50d · critical path: EXC → FND → FRM → ELEC → DRY → FIN → HAND
UTF-8 · LF · 12 lines · 482 chars✓ parsed·8.0 ms·7.6 KB SVG

What this shows

Once framing finishes, three trades — roofing, electrical, plumbing — run in parallel, but drywall can't start until all three are done. The engine works out that electrical is the longest of the three, so it lands on the critical path while roofing and plumbing carry float (drawn in blue with their slack). The critical chain Excavation → Foundation → Framing → Electrical → Drywall → Finishes → Handover is in red, and Handover is a milestone diamond. On a continuous calendar the bars span weekends; switch to calendar: 5day for a working-day timeline.

Gantt / PERT syntax →