Location

Working with Boston startups.

Boston builds serious software: healthtech, B2B, deep-tech. That work rewards rigor, and rigor is what a Holdfast sprint is organized around.

Time zone

Eastern Time (ET)

Overlap with Holdfast

Strong morning overlap, plus an overnight build window.

Rigor for healthtech and B2B

Boston’s healthtech density fits us well. We build AI features that stay inside approved sources and refuse to guess, tested with adversarial eval sets. For B2B, the bounded billing and integration work a sprint handles best.

Eastern overlap

Boston runs an hour ahead of Chicago, so the overlap window is wide. Decisions in your morning, building overnight.

Work

Sprints worth reading.

Healthtech

0answers given outside the source documents

Delivered in 14 daysName redacted

A RAG layer for a healthtech intake assistant, shipped in 14 days

The refusal behavior was the deliverable, not a side effect. Holdfast built an eval set designed to make the assistant fail and then made it pass. That is the rigor healthtech needs.

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Fintech

100%of historical transactions reconciled

Delivered in 13 daysName redacted

Ledger reconciliation for a Series A fintech, shipped in 13 days

They told us where AI did not belong, and the money math was top of the list. The engine is deterministic and auditable. Our monthly close went from three days to an afternoon.

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A feature to ship in Boston?

Send a one-page brief. A fixed price and a ship date back by morning, in your time zone.

Send a brief Or book a 20-minute call