Tom Geva

Limitrade

Market data for Roblox limiteds, priced from the live order book, with the evidence behind every number.

What
Market data
When
Sep 2026
Status
In development

Captured from a local run on real market data last crawled on 26 Sep 2026, which is why some panels read “13 d ago”.

The product

Limitrade reads the order books of Roblox limited items, infers the trades nobody publishes, and turns them into prices, liquidity and after-fee values. Every number can be traced back to what produced it. Not affiliated with Roblox Corporation.

The hard part

Roblox doesn’t publish individual sales. The only signals are an ask book that changes and an average price that moves. A price built from that is an inference, and a confident wrong one does more harm than none.

“A confidently wrong print is worse than no print.”

packages/valuation/src/prints.ts

How it works

  1. Trades, inferred from the book

    Sales are told apart from delistings by diffing the ask book, using five ranked evidence signals, each with a confidence. A trade is marked “Confirmed by RAP” or “Possible”, and you can open it to read why.

    prints.ts, EvidencePanels.tsx

  2. Fake offers, labelled

    Asks placed far above the market to look “not for sale” are classified with documented, tuned thresholds and shown as “Parked ask, not a real offer”.

    parked.ts, docs/PARKED_ASKS.md

  3. A value you can argue with

    Fair value blends the floor, inferred prints, VWAP and RAP, each weighted by how reliable it is right now, and keeps the full trail “so the UI can show exactly what produced the value and a user can argue with it.”

    fairvalue.ts

  4. Honest about accuracy

    A public Accuracy page reports the backtest even though the result is unflattering: right now the value does not beat RAP at predicting tomorrow’s price, 7.7% median error against 6.7%.

    apps/web/src/app/accuracy/page.tsx

  5. Polite by design

    A Redis-backed rate limiter is shared by every worker. The busiest items are read every 5 minutes and the next tier every 45. It never asks for a Roblox login.

    packages/roblox, packages/shared/src/tiers.ts

Inferred trades, one expanded to show its 92/100 confidence and the reason: RAP moved by exactly one sale at this price.
Every inferred trade shows its confidence and its reason.
Order book from the floor up with depth to clear, market facts and the after-fee sale value.
Trade check: a Downgrade −17,002 Robux verdict with warnings about a low-confidence value.
The Accuracy page opening with “Right now, our value does not beat RAP at predicting tomorrow’s price.”
The backtest is public, including the part that isn’t flattering.
Browse: thousands of tracked items with price, RAP, typical sale, 30-day change and sparklines.
Market home: “What Roblox limiteds actually trade for.”, a search box and a latest-trades ticker.

Facts, with sources

36,210
predictions in the published backtest, over 849 items
Accuracy page
2,784
items tracked in the development database
Browse page, local run
5 min
between order-book reads for the busiest items
tiers.ts
30%
marketplace fee taken out of every after-fee value (50% for UGC)
fees.ts

Details

Built with

  • TypeScript
  • pnpm monorepo
  • Next.js 15
  • TanStack Query
  • lightweight-charts
  • Fastify 5 + Zod
  • BullMQ
  • PostgreSQL + TimescaleDB
  • Redis

About these screens

  • Captured from a local run on real market data last crawled on 26 Sep 2026, which is why some panels read “13 d ago”.
  • Not affiliated with Roblox Corporation.
  • The code is in a private repository, so this page describes it at README level.