Software for contractors & fab shops

Built on the job site. Not in a boardroom.

HastaRex makes simple, focused tools that take paperwork off a project manager's plate: vendor invoices, spool sheets and pipe math. Each one was built by a PM to fix a problem he hit on his own jobs.

See the tools Talk to the founder
Free trial on every tool
Cancel anytime
Your data stays private
InvoiceFlow AI Accounts payable for contractors BullSheeter.AI Spool sheets to spreadsheets PipeFlow Rolling offset calculator
The tools

Three tools. One job each.

No bloated platform to roll out. Pick the tool that fixes your problem, try it free, and keep it only if it earns its spot.

For the office

InvoiceFlow AI

PMs · Accounting · AP teams

Stop keying vendor invoices by hand. InvoiceFlow reads them, matches them to your job POs and keeps your budgets current.

  • Reads vendor invoices automatically
  • Matches invoices to job purchase orders
  • Routes approvals to the right people
  • Job budget and cash flow reporting
$199 /mo per company
or $1,990/yr · 3 users included · extra users $39/mo · 14-day free trial
Start 14-day free trial

BullSheeter.AI

Fab shops · Detailers · PMs

Upload spool sheet PDFs and get a clean spreadsheet back. No more retyping drawings line by line.

  • Converts spool sheets into spreadsheets
  • Ready for takeoffs and shop tracking
  • Up to 500 pages a month
  • Your uploads stay private to you
$99 /mo
or $990/yr · 7-day free trial
Start 7-day free trial

PipeFlow

Pipefitters · Foremen · Shop

Rolling offsets worked out right the first time, on your phone, in the field.

  • Standard pipefitter rolling-offset formulas
  • Long- and short-radius elbow take-outs (ASME B16.9)
  • Cut lengths you can trust
  • Works on any phone or tablet
$12 /mo
or $99/yr · 7-day free trial
Start 7-day free trial
Why HastaRex

Made for how contractors actually work

Built from experience

Every tool came out of real projects: real invoices, real spool sheets, real offsets.

Simple to start

Sign up and use it the same day. No implementation project, no consultant.

Fair, flat pricing

Clear monthly or yearly plans. Try it free first and cancel anytime.

Your data is yours

Each customer's data is kept separate and private. We never share it.

HastaRex monogram
EST. 2026 · OKLAHOMA
About

A project manager who got tired of the paperwork

I've spent my career as a senior project manager and estimator in mechanical contracting, running large jobs across eastern Oklahoma. A lot of the week went to work no one should still be doing by hand: keying invoices, retyping spool sheets, double-checking pipe math.

So I built tools to fix it. HastaRex is where I'm making those tools available to other contractors, priced so a small shop can afford them as easily as a big one.

Blain Gerhart Founder, HastaRex Holdings LLC
Contact

Questions? Talk to a real person.

Whether you want a walkthrough, need help getting set up, or have a problem you wish a tool could fix, reach out. You'll hear back from me directly.

Email blain@hastarex.com Phone (307) 363-5009