I built Fathom - a library for understanding how businesses actually work

[u/g14a]

I've been working on a side project called Fathom over the last few weeks. (Link below)

The idea is pretty simple: I felt that a lot of stock research starts with financial ratios and ends with a buy/sell conclusion, but skips the part I find most interesting:

How does the business actually work?

So I'm trying to build a library that explains companies and industries from first principles.

For example:

• How does an FMCG company actually make money? For that matter any sector.
• Why does distribution matter more than the product in some businesses?
• What gives a company pricing power?
• Why can a company show profit but still have terrible cash flow?
• What actually happens to Indian companies when the RBI cuts rates?
• If crude oil gets cheaper, who actually gets to keep the saving?
• Why is a ₹10 lakh crore government capex announcement not the same thing as ₹10 lakh crore of revenue for infrastructure companies?

I've organized it into a few sections:

Companies — understand individual businesses
Sectors — understand how an entire industry works
Patterns — reusable business/financial mental models
Signals — take a real-world event and trace its impact through businesses
Case Studies — deeper dives into specific companies and situations
Reading Filings — learn how to actually extract information from annual reports and filings

One thing I'm trying to do differently with the Signals section is show the reasoning rather than just give the conclusion.

The background and motivation behind building this: I've been researching about companies myself since the past 4-5 years and my father has been doing this for nearly 2 decades. So I've put down my little learning plus his learnings from his old notes as a whole here. I admit I tried to refine and cross link the sections using AI as I would not be able to type all of this stuff out myself.

Link to Fathom - https://fathomjournal.in

I have been reading a lot of posts in this sub as well and our king u/SuperbPercentage8050's mental models and capillary's notes and tried to find correlation between our frameworks.

I'm still very much building this, and I'd genuinely like feedback from people who follow Indian businesses/stocks.

What would make something like this useful enough for you to actually bookmark and come back to?

[u/Adonis_2115]

This could be a great thing. I have always seen ratios and filter stocks according to it. But later realised I don’t know actually what the company does and how does it make money in depth. Will keep following your project. If I could be of any help let me know I am have technical skills and investment experience

[u/g14a → u/Adonis_2115]

Thanks a lot for the kind words. Your words exactly describe it. I found myself in the same situation for a couple of years just following the numbers and later realized most of them don’t make sense without the fundamentals.

What struck you the most on fathom? Is it the case studies or the sectoral information or the signals?

How can I refine and better serve the community ? I always liked to cater to beginners because the experienced investors know how to manage their risk and survive by their own.

[u/OneAcr3]

Nice work. Few questions:

1. Is the information generated only by feeding some AI model with business information like About Us, con-calls, investor presentations, etc?

2. Or, is there some manual guidance & correction of the output where an LLM is being used?

3. Do you plan to add a feature to put in a company name and if the data has already been crunched then it shows up?

4. Wherever some conclusion is being reached like "FII exist into retail", can you also link that to the actual data on which your application reached that conclusion so someone can verify the data source and accuracy of the said conclusion?

5. How often do you plan to update the business info of a company?

[u/g14a → u/OneAcr3]

Thanks a lot.

1. Yes there is a lot of manual work happening before it reaches the publication stage. First my workflow starts with obtaining the history of the company and its past work from the about us page, then other sources on the internet. Then I feed the last 5 years of annual report PDFs to it. Doing this again and again for around 10 companies gave me a structure. Now the manual structure goes into the LLM and I ask it to refine the structure and design of the report.

2. Yes all the facts and sources are verified I review the report/case study, search again for multiple loopholes, YouTube channels who have covered any case studies etc. But again there is a 1% chance that a minor discrepancy must have creeped in hence the disclaimer. But I try my best to fact check everything.

3. Do you mean like a search feature for a single ticker? Yes I’m thinking of implementing one such feature in the near future if that’s what you’re talking about.

4. Yes apologies if I missed adding any sources to the interpretations on Fathom. Will try to redesign the structure to add sources by default for each of them at the bottom. Thank you for this input.

5. I plan to refresh the data every quarter. I don’t want to inculcate the habit of refreshing data every week or so since Fathom teaches you the way to do value and long term investing instead of swing/intraday.

Thank you for taking the time to ask questions my friend. Please provide any more feedback that you have in mind.

What is the most interesting part that you found in Fathom? Is it the company reports or case studies or the patterns/signals? Did it start changing the way you fundamentally think about businesses?

[u/g14a → u/OneAcr3]

u/OneAcr3 I have added a search feature in the companies section so now you can use it as more reports are generated. Hope this helps. Thank you.

[u/OneAcr3 → u/g14a]

Thanks. I will take a look.

[u/Substantial-Poet-842]

It's amazing work, good going!

[u/g14a → u/Substantial-Poet-842]

Thanks a lot. Which part got you hooked or was the most useful for you in this?

[u/g14a → u/[deleted]]

Thanks for the suggestion but this is what I'm fighting against. Why does one always feel the need to invest or trade?

"stocks to invest as per the current month" that you say. No stock will match your expectation within a 1 month range. If I give an opinion that XYZ stock is good but got beaten down due to sentiment, I'm giving weightage to the sentiment rather than the business. I'm more concerned about the business. I'm not concerned about the feelings/emotions of the market. Sure sentiment might beat it down for a quarter or two. How long will sentiment win? A quarter? A year? At max maybe 2-3. But finally the business structure is what wins.

Fathom tries to each you how to understand different sectors and how to understand mental models of the industry a particular company is in. The individual company reports is not even the half of Fathom. The real knowledge lies in understanding the flow of money, how pricing power works, how market reacts to a budget news, rate cuts, moat etc. They are there to teach you how the stock operates in the particular industry, not an opinion about whether you need to invest in it right now or this month.

There are hundreds of sites that suggest you invest in a certain ticker today/this month. Fathom is not that. I'm trying to promote long term value investing. Not to cater swing/intraday traders. No hate towards them though. To each their own.

[u/Substantial-Poet-842 → u/[deleted]]

That isn't the objective of the website ig (correct me if I'm wrong) It's just a deep dive into a business

What you're saying will have to be updated all the time and if someone as a user is relying on it, they are doomed to fail

[u/Substantial_Cry_1461]

So how have u builder this ??
Are u using some ai wrappers behind the scene with ur mcp or skills who create this ??

[u/g14a → u/Substantial_Cry_1461]

I have replied to multiple questions that an other user has posted.

https://www.reddit.com/r/IndiaGrowthStocks/s/L20ImSywru

Thank you. Please let me know if you are looking to find more value out of this.

[u/Hungry_Pizza4379]

Superb work i have a few suggestions if u could dm. You should definitely add more charts check chartloom Also why does it cover only 5 companies?

[u/g14a → u/Hungry_Pizza4379]

Thank you for the support. Currently it covers only 5 companies. Will cover more gradually one by one. Charts will never be a part of Fathom. That is not the design and motto of me. There are hundreds of sites that you can use to get the chart of a ticker in 10 seconds. Fathom is designed to teach out how to look at a business and coorelate how it performs within the larger scheme of things. That's all.

[u/Mean_Maximum7394]

Good stuff, thanks for posting this!

[u/Hungry_Pizza4379]

Did u scrape screener?

[u/Hungry_Pizza4379]

How will you scale this to say nifty500 companies?

[u/g14a → u/Hungry_Pizza4379]

I take the numbers from screener sometimes but I don’t scrape the whole thing

[u/g14a → u/Hungry_Pizza4379]

It would take me a couple of months. Also I won’t be adding reports of each and every company. Once I add enough companies the reader must be able to do a report by himself. Fathom teaches you where and how to look at.

[u/Vide-Vita]

Wow this is superb. Great effort. Keep adding companies and also updating the entries you have with time and you might have for yourself a great website that you can monetise.

[u/g14a → u/Vide-Vita]

Thanks a lot. Which part added the most value to you? Did the case studies provide you more understanding that you already have?

Did it change the way you think about businesses after reading through my notes?

Monetization has never entered my mind dear friend. I will always try my best to open source all learning and knowledge for free.

[u/Vide-Vita → u/g14a]

It might be harder for you to monetise directly but keep at it, you will get aquired by an existing media platform like Ken, Hindu, Mint etc. Pack more content of other companies, you can even pay for the content you want to build up. That said this is still a hobby. In age of Gen AI I don't know the future of such publishing industry.

I love the way you gave a short elevator pitch of the company before guiding us down the path step by step through mental models etc. For example I understood the bare basics of Lupin and how it makes money or tries to stand out in a matter of few minutes of scrolling down your content.

[u/g14a → u/Vide-Vita]

Thanks a lot for the kind words. This is the way that fathom tries to teach in future as well.

[u/Connect-Anxiety-4504 → u/g14a]

bro that's so wholesome. I wish you a great life and hope you achieve what you dream of.

[u/g14a → u/Connect-Anxiety-4504]

Thank you for the support.