Fathom 2.1 — the living model of your fund

Made for the Mac

Feels like a native Mac app.

Drag a mark and watch the map move

Each tile is a company, sized by its value at your marks. Drag the ruler and the tile resizes as you go. The scale is logarithmic, so $50M to $500M is the same distance as $500M to $5B.

Color-coded cases

Each scenario gets its own color, and the window picks it up so you know which one you’re in.

Peek at the real book

Hold Option in any case to see your admin’s numbers. Let go to return.

Jump anywhere

Funds, companies, cases and commands, from the keyboard.

Eleven palettes

Each has a light and a dark version.

In the meeting

Answer questions immediately.

A partner or LP asks a what-if. You change the marks and answer it on screen.

Exit“If Fund III winds down at 3×, what do LPs actually get back?”

Stress test“Mark the whole book down 40%. Where does each fund land?”

Pro rata“If we put $3M into this round, what do we own after it, and what’s left in reserves?”

Ownership“Exact check to hold 4% through this round?”

Timing“Same 3× outcome, but it takes until 2030. What happens to IRR?”

Concentration“What does Fund II look like if the top company goes to zero? If it doubles?”

Benchmark“Do we beat the S&P on the same cash flows, and by how much?”

Portfolio

See where the value is.

Every company across every fund on one map, sized by value at your marks. The long tail collapses into a single tile. Switch to the list to sort.

Portfolio map: every company as a tile, sized by value and colored by fund

The inspector

Reprice without losing your place.

Companies open in a side panel, so the fund numbers stay visible while you move a mark. To model the next round, enter the raise, the post-money and your check to see dilution and your pro rata.

Dragging a company’s valuation ruler, then modelling its next round

Funds

A page for each fund.

The fund’s own map first, shaded by multiple or by what this case changed. Then NAV, TVPI, DPI and net IRR at its marks.

New in 2.1

Turn a case into an LP deck.

Pick the funds, write the story on the slides, hide anything you’d rather not show, and save it as a PDF. Your marks sit next to your admin’s books on every page.

Case Report: a case laid out as slides for LPs, with partner estimates beside booked values

The firm

Carry, LPs, pacing and benchmarks.

These reprice with the case too. Carry and LP pages stay private unless you share them.

Accrued carry by fund and by partner, with each partner’s share broken out fund by fund.

How it runs

Your data stays in the office.

It reads from Carta, AngelList, another admin or a spreadsheet, and never writes back. It runs on a Mac mini that’s only reachable over Tailscale, and serves a production build that’s checked after every update.

Built withClaude Code

DataYour fund admin, read‑only

Runs onA Mac mini behind Tailscale

AccessYou and your partners

We built this for our own firm.

We use it in most partner and LP meetings. If you’re a GP and want it, DM me and I’ll show you how to set it up.

DM @jtriest on X

The living model of your fund.