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Three weeks ago I posted a tool that reproduces Burry's stock-comp math. It's now a free toolkit, and strangers' criticism made it better. Update inside.
Three weeks ago I posted a tool here that reproduced the stock-comp method from Michael Burry's Cassandra Unchained articles. Since then it grew into something bigger and I think the update is worth sharing, including the parts where I was wrong.
**What it is now.** A free web app, no signup, one page per question: [https://investor-toolkit.streamlit.app/](https://investor-toolkit.streamlit.app/)
* **Tragic Algebra Analyzer**: Burry's method as published. Measures the true cost of stock compensation (market value of shares delivered, not the GAAP charge), owners' earnings, and an intrinsic value at a 15% required return.
* **Hundred Bagger Checker**: Christopher Mayer's framework plus Burry's ROIC formula. Does the arithmetic of a 100x actually close for this company.
* **Inflection Checker**: companies crossing from losses to profit. The margin path, priced or refused.
* **Financials Checker**: banks, insurers, REITs and client-asset brokers on tangible book, returns and payout. The other pages refuse financials and send you here.
* **Non-US Checker**: IFRS filers, ADR ratios, or paste your own figures for anything not on EDGAR.
* **DCF Evaluator**: the standard two-stage DCF everyone prints (Damodaran's framework), shown next to the same DCF on SBC-corrected cash flow. The gap between the two columns is what the standard definition hides.
* **Expectations**: a reverse DCF (Rappaport and Mauboussin). It never tells you what a company is worth. It solves what today's price implies, then shows you the company's own best filed growth stretches and how many of the names in its base table ever sustained the implied rate. You judge.
* **Return Calculator**: plain compounding arithmetic, now with dividend reinvestment done properly.
Every number is read from SEC filings. Every page refuses out loud when it can't stand behind a figure, and says why. There are about 1,600 self-checks across the pages and you can run them yourself from any page's footer.
**The part where I was wrong.** A commenter here showed that a compounding claim in my original post didn't follow from the math: the retention ratio in the method is a level ratio, not something you raise to a power. He was right. The valuation engine was never affected (it applies the ratio once), but one paragraph of the post and one metric label repeated the bad claim. Both are fixed, with edit notes, and the exchange is in the original thread if you want to see a stranger do proper peer review for free.
**What the verification machinery found.** The interesting one: the app keeps a regression suite that compares its live output against every figure Burry published. Chasing the disagreements found real bugs, including one where a treasury-stock line equal to the year's buyback was being counted as tax withholding, charging the same dollars twice. That single test, once written, found the same double-count at four more companies, including one sitting in the app's own control set. Chasing another disagreement found that Adobe files its pre-2019 tax withholding under a custom XBRL tag literally named CostOfIssuanceOfTreasuryStock, which no aggregator API can even see. The app now reads it from the filings directly, verified against the filed figures or not at all. Twenty-one of the twenty-three rows in Burry's published tables now reproduce on the live app; the two that don't are documented on the page to the dollar, with the open question stated.
If you type MRVL into the Expectations page you'll see the kind of answer this toolkit is built to give: not "overvalued", but the exact growth path the price implies and how often anything in the base table ever delivered it.
**Disclosure, same as the original post:** I'm a retail investor, not a programmer. The code was written by AI (Anthropic's Claude) in long sessions where I ran every version against real filings and screenshots until the numbers reconciled. The method is Burry's, Mayer's, Damodaran's, and Rappaport/Mauboussin's, all named on their pages; the project is independent and not affiliated with or endorsed by any of them. Not financial advice, obviously.
It's free and staying free. If you break something, and someone here probably will, I genuinely want the ticker and the screenshot. The tag panel on every page shows exactly which filed figures were read, so a bug report can be precise. Repo: [https://github.com/ChenFindling/tragic-algebra-analyzer](https://github.com/ChenFindling/tragic-algebra-analyzer)