Work

Work.

Twelve sprints, four embedded engagements, since founding. Here are the ones written up in full, internal lab projects and external client work alike.

Stack

Industry

Type

Healthtech

4.2xqualified recruiter matches vs. manual search

Delivered in 12 daysApplyAI

A recruiter-finder agent for ApplyAI, shipped in 12 days

Holdfast treated our cost ceiling as a hard requirement, not a nice-to-have. The agent does one thing, does it cheaply, and tells us when it is unsure. That last part is why we trust it.

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B2B SaaS

0billing disputes after launch

Delivered in 9 daysLovedPDF

Stripe metered billing for LovedPDF, shipped in 9 days

They shipped billing code I did not have to double-check. The shadow cycle meant every customer saw their number before it hit a card. That is how you change pricing without losing people.

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Consumer

14 / 14shipped on the exact deadline

Delivered in 14 daysMyHomeversity

Hyde Park student housing referral flow, 14 days, exactly on time

This one ran tight and still landed on day 14. The buffer was in the plan from day 1. That is the difference between a deadline and a hope.

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B2B SaaS

8 weeksembedded, comparison engine v1 live

Embedded, 8 weeksMatchYourSaaS

A comparison engine for MatchYourSaaS, embedded for 8 weeks

Embedded meant I got an engine, not a feature. Weekly cadence, monthly written review, every score explainable. It felt like having a senior engineer on staff without the 12-month contract.

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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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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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