About

AI that speaks the
language of the job site.

openmud is an open-source AI platform built for heavy civil and underground utility construction — estimators, project managers, supers, and field engineers.


Mission

Make AI a practical tool for every phase of the job.

Most construction software is built by people who've never run a crew, never bid a job, never stood at the bottom of a 10-foot trench figuring out soil type. The tools don't speak the language. The pricing data is wrong. The AI gives generic answers that would get you fired on a public works project.

openmud is built differently. The AI is trained on actual construction context — pipe sizing, trench specs, labor and equipment rates, bid structure, OSHA standards. The calculators use real engineering equations. The resources are sourced from public domain federal standards, not generic safety content. And the whole thing is open source, so people who actually know the work can make it better.

The goal: from bid to closeout, openmud has a tool, a reference, or an answer. Free. No paywall. No lock-in.


Navigate the platform

What's here and where to find it.

AI Chat — /chat
Multi-model AI chat tuned for heavy civil. Ask about costs, pipe sizing, scheduling, trench depth, compaction specs, or anything construction. Supports GPT-4o, Claude Sonnet, and mud1 (our custom heavy civil model). Bring your own API key or use it as-is.
Calculators — /calculators
18 construction calculators across four categories: Takeoff & Quantities (trench volume, concrete, asphalt), Engineering & Field (pipe flow, minimum slope, OSHA safety, thrust blocks), Cost & Bid (markup, unit price, change order, production rate), and Reference (unit converter, pipe table, Manning's n). All run client-side — no account.
Resources — /resources
Structured reference content: OSHA 29 CFR 1926 Subpart P (trenching/excavation), 811 Blue Stakes guide with utility color codes, confined space entry standards, pipe specifications, soil classification with swell/shrink factors, Manning's n table, curated YouTube channels, construction news sources, open-source tool directory, and a searchable 60-term field glossary.
Companies — /companies
Directory of 50+ construction companies. Utah contractors. ENR Top 25 national. ESOP and employee-owned firms. Publicly traded companies with tickers. Underground specialty contractors. Plain-English explanation of ownership types, what an ESOP actually is, and where the market is heading with $1.2T in IIJA spending.
Python Tools — /tools
Standalone Python library: Manning's equation, trench takeoff, thrust block sizing, asphalt tonnage, concrete volume, OSHA trench safety reference, unit conversion, markup math, production rates, crew day cost, change orders. MIT licensed. Import into your own projects. pip install coming to PyPI.
GitHub — Open Source
The whole platform is open source. MIT license. 75 automated tests, CI on every PR, issue templates, PR template, AGENTS.md for AI contributors. Contribute better pricing data, new calculators, improved AI prompts, integrations, or anything that makes heavy civil work better.

Contech API

Build on top of it.

The estimating and chat engine is available as an API for integration into your own tools and workflows. If you're building construction software and want a working AI backend tuned for heavy civil, openmud's API is a starting point.

API status: checking…

API documentation API.md on GitHub →

Contact

Get in touch.

If you work in construction and want to contribute, have better pricing data, or want to talk about what openmud is building — reach out.

hi@masonearl.com → GitHub Discussions