Show HN: I spent 3 years reverse-engineering a 40 yo stock market sim from 1986

Sorry for LLM flavor in the article. It's valid criticism and I will rewrite it when I get the chance. I just wanted to share the story and I didn't have time to write it completely from scratch, plus I'm not that great of a writer. I thought filtering my thoughts through LLM editor would eliminate the distraction of my poor writing abilities, which for most people I think it worked. For others, it created another distraction, ragebait in fact, which was not my iuntention. So between working 80 hours a week at the prompt factory and raising two kids I will find some time to de-ragebaitify the article, although it seems to have unintentionally propelled it to the front page, for which I am admittedly thankful for.

This is such a well written story, and congratulations Ben, it sounds like it's been a lot of hard but ultimately successful work!

I know you'll deservedly get a lot of credit for all your work in remastering the game, but you should also get credit for how you've woven this narrative together, it's a lovely read. Thank you for taking the time to write it up, and good luck with the Steam release, and whatever project you take on next! :)

This was an interesting story, but implying this is some unique insight irked me a little - perhaps because it is LLM-flavoured text that hypes it too much, and makes it sound like some kind of major breakthrough? Keeping the original game as-is, underneath a modern port 'layer', is a pretty popular and common way to update things, you can see it being done in a bunch of modern remasters.

Congrats on such an achievement. The remake looks great, but those DOS screenshots have an undeniable charm. With such a large scale game, something I always find interesting is uncovering what types of quirks and bugs bubble underneath the surface in the original version. Did you come across anything obvious in your testing?

This is my favorite thing I’ve read on Hacker News, ever. Congratulations Ben and Michael, I’m so glad you both had the tenacity to make this happen. Well done.

As the saying goes, strike while the iron is hot. Wall Street Raider will be released to Early Acces on March 12, 2026. https://store.steampowered.com/news/app/3525620/view/5951738...

I think it is pretty unreasonable to call CP/M "primitive beyond belief". It was basically equivalent to MS-DOS in capability -- after all, MS-DOS was basically an unlicensed clone of CP/M for the 8086.

You can tell that by the end of it you got tired and it's less manually edited and more straight from the LLM's mouth.

I don't really care in this case though, it's an awesome story and it doesn't detract too much. Congratulations!

A technical question for you around the porting being a dead end:

I see from other replies that you now understand the code reasonably well and feel you can expand/extend it while keeping it in BASIC. However, I note you've also done project where you automatically ported Fortran to Lua - are you not interested in trying to do something similar for performance/maintainability reasons? Is there an advantage in keeping it in PowerBASIC?

I've wish listed the game, and look forward to playing it, it sounds like great fun - even the manual sounds like a good read.

Tenuous relevance, but a different stock market game written in BASIC on the Apple II (well, I only had access to the Franklin Ace clone) was my initial motivation at age 10 or so to try programming. It was a pretty thrilling amount of power to a 10-year-old to be able to rename all the companies after my friends or whatever jokes I wanted, and next to alter the rules to get more money. It’s a good thing BASIC was everywhere in the 80s — so many books and computer manuals had enough information that it was easy to find a source to learn the (no pun intended) basics.

You should either bundle the DOS version with the game, or release it separately somewhere. If you broke the DOS frontend and don't want to get it working again, maybe release the last working DOS version?

Consider releasing on GOG. This game is great nostalgia bait, and if you release the DOS version, the GOG staff are quite experienced at building modern, cross-OS installers for DOS games and tuning DOSBox.

FWIW I never played this particular game but around the turn of the millenium I put probably over 100 hours in Trevor Chan's Capitalism games [1].

[1] https://www.gog.com/en/game/capitalism_plus

My "learn options trading" environment, I realized after reading this, really needs a news feed to get a feel for what is happening in the virtual world of the test trading, so I added one today. Still very much playing around with it, the alpha is at https://trading.linsomnaic.com/

Reading between the lines, the game logic itself hasn’t been reverse engineered yet, so adding, changing, or fixing logic still means working with the original code that only Michael Jenkins understands to this day. In any case: massive props to Ben. This feels like a strong foundation, and I’m excited to see him continue evolving the game.

Regarding "The Second Oldest Game Developer", there are also the authors of "Spacewar!": Steve Russell was born in 1937, meaning, he's either 89 or will be 89 this year. Dan Edwards must be around that age, as well.

So what kind of source code can be so difficult to understand?

I've always wanted to get my hands on the Championship Manager 92/93 source code to see what gave it its "soul". What made that version so special.

What a beautiful story. Thank you for sharing! As a mechanical engineer with barely any knowledge or inclination towards coding and/or finance you persuaded me to look into the game.

I admittedly only googled quickly but is there anywhere I can buy the original and the book still? I understand he had issues with the payment processor, and I can see free versions to download but I'd prefer to do it legitimately if possible

I'm sure there is truth in original author saying tax code complexity as the core challenge. But that's not what makes this hard. That's domain complexity we all come up against it's accidental complexity that killed the ports.

The real problem is idiosyncratic and esoteric coding practices from a single self-taught accountant working in a language that didn't encourage good structure.

I can translate well-written code without understanding what it does functionally, so long as I understand what it's doing mechanically.

The original author seems to build in the assumption you're not going to translate my code you'll need to rewrite it from the the tax code!

Such fun for you and the author! I've never played the original game but now I wanna!

Really cool article! The solution to wrap the engine in a modern UI was a good one. I would have fallen to the trap of trying to port the whole thing, like all the other companies did.

Out of curiosity, how are the things tested? Or is checking core-engine doing things right only up to the developer and their tribal knowledge?

This story is super interesting and I think can teach us some valuable lessons about refactoring and the price of truly understanding the domain in which the code operates. The accompanying article is also a pleasant reading with a nice bit of background, and I really liked the motivation behind "layering" on top instead of rewriting from scratch.

Thanks for bringing this story to HN!

Well that was a pretty cool story. Really enjoyed that it was sufficiently good for its time that so many people got into the field after enjoying playing it (or perhaps that it was enjoyable enough for so many destined for the field to use). And loved the bit where someone emails him and a few chats later off he sends the source code.

Good job! When can I buy it?

I am sold on the game and wishlisted it but lack of release date saddens me.

I love spreadsheet games like Terra Invicta/Paradox/Simutrans and this seems like a terrific example of one.

This is very well written. I have fairly low interest in video games and rarely read gaming content, but read this all the way through. That’s an achievement in itself!

> The game he wanted to make required something that didn't exist yet: a personal computer.

> So Jenkins waited.

This part made me laugh out loud. It made me imagine Jenkins as a time traveller who had made a mistake and got stuck in the past, but knew that personal computers would be invented.

If you dropped the source code here you'd probably get a versiojn in each of the 5 major languages quick smart.

I enjoyed the read. How did you tap into the legacy Power Basic engine? Was there a FFI or some kind of bridge you could hook into? And what languages were you using?

3 life years well spent. ggg

Ben, that was one of my favorite "internet" stories... What a beautiful generational link!

Really interesting, thanks for sharing!

I know it almost sounds crass, but you should consider letting an LLM take a crack at transpiling the code. Source to source translations are one of the most widely agreed upon strengths of LLMs.

Looks like I’m going to need a Windows 10 virtual machine on my Apple Silicon. Or maybe I’ll just buy my first Windows machine since 2001.

Ben, thanks for working on this! I instantly flashed back to the mid to late 80s when I saw the screenshots; I’m certain I played this game as a pre-teen. Just let us know how we can buy it.

I haven't heard the lore on this one, why is there interest in this?

I loved this game. As soon as I saw the title I knew it would be Wall Street Raider. I play it via dosbox and for me the UI is part of the charm. I’d be interested in tinkering with the pricing simulation but from the article it seems like that’s almost impossible.

This is a wonderful project, and the post is a wonderful read!

Are there any plans to break out portions of the Basic engine to a modern language? It's frustrating that the heart of the game remains inscrutable. Surely Ward is tempted?

This was a great thing to read this morning, kudos to both!

The Wall Street Raider is under active development, you’re releasing a clone under the same name?

https://www.roninsoft.com/wsraider.htm

This is amazing! Having no knowledge of Basic, a.) what makes the rewrite "impossible"? b.) how do coding agents perform on the codebase? It might make for a neat benchmark similar to ARC

I read this in it's entirety. Not skimmed through it, but read every single word (took about 30 minutes)

You can imagine my disappointment when in the end, the code is still basically a mystery, and a wrapper around the core game was made.

Not because what you did is not hard or impressive, it's because, up until the line were you said you are going to use a wrapper, you made it seem like you're deciphering the code. That isn't really clickbait, because I had already clicked and spent 20 minutes reading. Being misled felt a bit bad, considering how beautifully the story is written.

Impressive work nonetheless.

If you could get an LLM to write the article, why not just get it to rewrite the code?

... You got the source code, and it was 115 kloc of BASIC, but several other individuals and organizations failed to "reverse-engineer" it?

1) this is super interesting

2) the prose is very LLM-flavored, but for once I don’t mind. It’s obvious to me that this blog post only exists because an interesting, intelligent person used an LLM to lower the cost of extracting complex ideas from their brain.

3) the “Fits of Rationality” process sounds a lot like how coding agents work. They’re alive in the moment, then later all they have to work with is the written record of their previous sessions. The Herculean effort to re-implement the result foreshadows the vibe-coding repair industry.

Cool! Was looking for something like this all through the 90s :)

"fits of rationality" is a great line.

Awesome story! Well-written also.

You are the engineer we all aspired to be. Though, you really are the chosen one.

Wish you the best!

Amazing read! Is it possible to do something like this but for wall street raider?

https://labs.ramp.com/rct

"claude code plays wall street raider" would be very very cool.

Congratulations Ben! The game sounds like a dangerous cult that I want no part of. But I've also done game ports recently and was curious - how much of the old codebase did you need to understand (and change!) in order to port it? And how much could you just wrap up / virtualise, and start building on top?