v4.0.0 — Stable 4.0 · production-ready platform

First stable 4.x release. Same code base and install procedure as the latest 3.12 patch; the version cut signals that the platform is now considered production-ready across the full estimation → takeoff → BIM → BOQ → tender → reporting workflow, with a stable public API surface, multi-tenant security pass complete, and 103 modules shipping in the box.

What "stable 4.0" means

• Stable public API surface. Every /api/v1/* endpoint shipped in 3.10.x → 3.12.x is now part of the public contract. Breaking changes will be marked /v2; 4.x patches will only add fields and endpoints, not rename or remove existing ones. OpenAPI spec at /api/openapi.json is the source of truth.
• Multi-tenant security pass complete. Cross-category IDOR sweep closed ~73 endpoints across Planning / Communication / Procurement / Documents. Every project-scoped route enforces verify_project_access; every owner-scoped route enforces inline owner_user_id comparison with 404-not-403 on mismatch.
• 103 modules ship in the box, dynamically discovered by the module loader. All have backend + frontend + tests + i18n + permissions.
• CAD/BIM pipeline is canonical-format-first. Every CAD source (DWG, DGN, IFC, RVT) goes through the DDC cad2data converter into a canonical JSON. No IfcOpenShell dependency. BCF allowed as I/O for issues + viewpoints + validation reports. Serve-time magic-byte validation guards the viewer against corrupt blobs.
• Cost database: 55,000 priced positions in CWICR, plus 30+ regional v3 catalogues. Multi-currency BOQ with FX-correct exports. Vector search via Qdrant; multilingual semantic match across 24 languages.
• i18n: 24 languages. EN/DE/RU/zh-Hans/pt-BR/Mongolian are deep native quality. The remaining 17 ship with English defaultValue fallbacks; native pass continues in 4.0.x.
• Self-host story: one command. pip install openconstructionerp && openconstructionerp boots PostgreSQL-or-SQLite + 103 modules + Qdrant ping + showcase snapshot seed + alembic upgrade. AGPL-3.0 community; commercial licence for source-modification protection.

Highlights rolled up since v3.0

• BIM Hub pro-grade — Site Compass cube, Solo Mode, Trait Lens color-by-property, Element Bundles selection sets, viewpoint state with camera + filter + clip + thumbnail, screenshot export, DDC converter version badge, property search panel.
• Clash Detection — schema + DBSCAN engine + FP-mining + 6 REST endpoints, KPI dashboard with severity / discipline-pair / top-clashing-pairs / MTTR, rule editor + suggestions banner.
• Takeoff pro-grade — PDF + DWG measurements, PaddleOCR + YOLO symbol detection, jsPDF export with annotations, exceljs export with per-group subtotals.
• BOQ pro-grade — bulk multiply rate / qty / classification, per-cell field-history restore, Ctrl+D fill-down + Ctrl+; today, multi-level hierarchy with 8-deep nesting, reusable/linked positions, FX-correct CSV/Excel exports with frozen FX appendix.
• Match Elements — 7-stage visible pipeline (Convert → Load → Schema → Filter → Group → Match → Rollup), per-stage adjust, vector + lexical + resource matchers, currency-aware rollup, catalogue + display-currency picker.
• Cost Intelligence — regional indices + cost-item usage telemetry, certainty bands (green/yellow/red), live regional-adjust panel.
• Files CDE — saved views rail, tag-filter facet, version history with "Make current", 24h trash purge, per-recipient notification fan-out on new revision.
• Validation@Import — DIN 276 + GAEB + NRM + MasterFormat + BOQ-quality + project-completeness rule packs wired into GAEB / Excel import path; GAEB X84 (Nebenangebot) export writer.
• BI Dashboards — 5 role-based starter dashboards (CEO / CFO / PM / Site / Safety), 14 system KPIs with 12-week history, 3 reports, 2 schedules, 4 alert rules — installed via idempotent one-click endpoint.
• AI services — embedding-pool with prewarmed workers, FSM-driven match pipeline, BIM placeholder geometry fallback, Mongolian + Devanagari OCR, lakh-crore numeric parsing, UTM CRS for 16 regions.
• Ecosystem — license-request page with 90-day affiliate cookies, marketing site with 34-card module grid mirroring the in-app sidebar.

Upgrade

:::bash
pip install --upgrade openconstructionerp
alembic upgrade head
systemctl restart openconstructionerp

Alembic head: v3096_regional_indices_certainty. No migration steps required from 3.12.x.

Licensing and third-party software

This release is distributed under the GNU Affero General Public License v3.0 or later (community) with an alternative commercial licence available for source-modification protection (contact info@datadrivenconstruction.io).

Two optional dependencies in the [cv] extra are themselves AGPL-3.0:

• PyMuPDF (Artifex Software, Inc.) — AGPL-3.0
• Ultralytics YOLO (Ultralytics Inc.) — AGPL-3.0

Users who install the [cv] extra and operate a modified version of OpenConstructionERP over a network are subject to AGPL-3.0 obligations both from OpenConstructionERP and independently from those upstream projects. Commercial users who require a non-AGPL path for the computer-vision takeoff pipeline must obtain commercial licences directly from Artifex Software (PyMuPDF) and Ultralytics Inc. (YOLO).

Users installing without the [cv] extra do not pull in these AGPL upstream packages.

Third-party software inventory

Full machine-readable license inventories attached as release assets:

• NOTICE.backend.json — pip-licenses output for backend base + extras (116 packages)
• NOTICE.frontend.json — license-checker output for the compiled frontend bundle (283 packages)

Distribution

• PyPI: https://pypi.org/project/openconstructionerp/4.0.0/
• Demo: https://openconstructionerp.com (demo@openestimator.io / demo)
• Marketing site: https://openconstructionerp.com
• Source: https://github.com/datadrivenconstruction/OpenConstructionERP

Trademarks

Revit®, AutoCAD®, DWG™ are trademarks of Autodesk, Inc. MicroStation®, DGN are trademarks of Bentley Systems, Inc. IFC® is a trademark of buildingSMART International. DIN is a registered trademark of DIN e.V. GAEB is a trademark of the Gemeinsamer Ausschuss Elektronik im Bauwesen. NRM is a trademark of RICS. MasterFormat® is a trademark of CSI. OpenConstructionERP is an independent project and is not affiliated with, endorsed by, or sponsored by any of the trademark owners listed above. Comparative references to commercial products reflect publicly available feature information at the time of publication and are used for fair comparative purposes under EU Directive 2006/114/EC and US Lanham Act §43(a).