{"slug": "ai-lmc-phase-00-i-just-wanted-to-make-easy-money-with-ai-so-obviously-i-m-now-a", "title": "AI-LMC Phase 00 — I just wanted to make easy money with AI, so obviously I'm now building a legacy app from scratch 🐼 (Part 1)", "summary": "A developer with 11 years of experience in C# and .NET, mostly on internal B2B systems, is exploring legacy modernization as a way to make money with AI. The developer notes that 61% of user companies in Japan still have legacy systems, and .NET 8 reaches end of support in November 2026, making upgrades to .NET 10 a current need. The developer questions whether AI tools like GitHub Copilot modernization can handle the messy reality of legacy codebases.", "body_md": "I want to make money with AI.\n\nIdeally, easy money.\n\nTo put it more precisely:\n\n**I want to hand as much as possible to AI, and do as little as possible myself.**\n\n🐼 \"Is there a convenient method like that somewhere?\"\n\nSo I asked the AI first.\n\nWhen I scroll through social media, I keep seeing people overseas post things like:\n\n\"I made money by having AI do this.\"\n\n\"I built this system and it just runs on its own.\"\n\nMust be nice.\n\nI want that too. 🐼\n\nBut some of those services can't be used from Japan.\n\nFor example, **[Polymarket](https://help.polymarket.com/en/articles/13364163-geographic-restrictions)**, the prediction market you see a lot overseas, currently lists Japan among its blocked countries.\n\nAnd there are plenty of others. You find some clever scheme going viral abroad, and then:\n\n\"Great, let's just do that in Japan!\"\n\n…turns out you can't.\n\nSo I asked my GPT and my Claude.\n\n🐼 \"I want to hand things off to you two and get to a point where I make money without much effort.\"\n\nWe talked about a lot of things.\n\nA lot of ideas came up.\n\nBut in the end, GPT and Claude both circled back to roughly the same place.\n\n🤖 \"The fastest route is to use the eleven-plus years of engineering experience you already have.\"\n\n🐼 \"…So we're back to that?\"\n\nI've been an engineer in Japan for about eleven and a half years.\n\nMostly C# and .NET.\n\nBut when I look over the résumé of those eleven years, it's almost entirely internal systems and B2B line-of-business applications.\n\nI haven't built consumer web services.\n\nI haven't maintained a well-known open-source project.\n\nWindows applications used inside companies.\n\nPoint-of-sale systems.\n\nSystems built to make some back-office process less painful.\n\nThat's what I've been making, the whole time.\n\nAnd in this kind of work, some projects restrict the use of generative AI entirely, because the systems handle confidential and personal data.\n\nNaturally, none of that source code is on GitHub either.\n\nSo when I go looking through GitHub issues and public job listings thinking:\n\n🐼 \"Maybe I can get AI to do this part and take it easy\"\n\n…the kind of work I've actually done for eleven years doesn't show up.\n\nOf course it doesn't.\n\n**They're internal systems.**\n\n🐼 \"So what am I supposed to do with my eleven years in the age of AI?\"\n\nGPT and Claude gave more or less the same answer to that one too.\n\n**Legacy Modernization.**\n\nI looked into it.\n\nAccording to a 2025 report from [Japan's Digital Agency](https://digital-agency-news.digital.go.jp/articles/2025-08-27-1), based on the summary report of the Legacy System Modernization Committee:\n\n**61% of user companies still have legacy systems.**\n\nAmong large enterprises:\n\n**74%.**\n\n🐼 \"That's a lot.\"\n\nMy eleven years of line-of-business experience applies.\n\nC# and .NET apply.\n\nAnd there's still a mountain of legacy systems out there.\n\nRight then.\n\n🐼 \"So I do Legacy Modernization and I get paid?\"\n\n🤖 \"No.\"\n\n🐼 \"…\"\n\n**.NET 10** was released in November 2025.\n\nThanks as always, Microsoft. 🐼\n\nAnd [.NET 8 reaches end of support on November 11, 2026](https://learn.microsoft.com/en-us/lifecycle/products/microsoft-net-and-net-core).\n\nWhich means upgrades like:\n\n`.NET 8 → .NET 10`\n\nare exactly what people are doing right now.\n\nMicrosoft also already has **[GitHub Copilot modernization](https://learn.microsoft.com/en-us/dotnet/core/porting/github-copilot-app-modernization/overview)**.\n\nIt analyzes a .NET project, produces an upgrade plan, modifies the code, and verifies the build and tests.\n\nThere is an official scenario for exactly this: \"upgrade this solution to .NET 10.\"\n\n🐼 \"So AI can already do it.\"\n\nAnd here's where something caught.\n\n**Really?**\n\nI mean, sure.\n\nRewriting the target framework. Updating NuGet packages. Fixing compile errors.\n\nAI is going to keep getting better at all of that.\n\nBut.\n\nThe legacy line-of-business systems I've actually seen — were they ever that tidy?\n\nFor example.\n\n\"Only A-san understands this part.\"\n\n\"Where's A-san?\"\n\n\"Quit last year.\"\n\nOr.\n\n\"The spec says this, but that's not how it actually runs.\"\n\n\"Which one is correct?\"\n\n\"You'd have to ask the people who use it.\"\n\n\"Why is this one number corrected by hand?\"\n\n\"It's always been done that way.\"\n\n\"Who decided that?\"\n\n\"No idea.\"\n\n\"We could probably delete this, right?\"\n\n\"No — apparently some department has a problem at month-end if you remove it.\"\n\n\"Which department?\"\n\n\"Accounting, probably.\"\n\n\"Probably?\"\n\nIn a legacy business system, **reading the source code is not enough.**\n\nIt isn't in the documentation.\n\nThe spec is out of date.\n\nOnly one person knew.\n\nAnd that person is gone.\n\nSo an engineer goes around asking.\n\n\"What is this process actually for?\"\n\n\"How am I supposed to decide this value?\"\n\n\"Is this workflow still in use?\"\n\nI've watched that happen many times.\n\nWhich is when it occurred to me.\n\n🐼 \"Can AI figure this out too?\"\n\nIf you analyze the source code, **can you really recover the things that used to require asking someone?**\n\nEven human engineers couldn't. They went looking for the person who knew, asked the question, failed to get an answer, and decided for themselves in the end.\n\nCan AI really work all of that out?\n\n🤖 \"That question itself is interesting.\"\n\n🐼 \"Hm?\"\n\n*Part 2 continues.*", "url": "https://wpnews.pro/news/ai-lmc-phase-00-i-just-wanted-to-make-easy-money-with-ai-so-obviously-i-m-now-a", "canonical_source": "https://dev.to/puyun_days/ai-lmc-phase-00-i-just-wanted-to-make-easy-money-with-ai-so-obviously-im-now-building-a-legacy-3nan", "published_at": "2026-09-08 11:09:29+00:00", "updated_at": "2026-09-08 11:31:51.626605+00:00", "lang": "en", "topics": ["developer-tools", "artificial-intelligence"], "entities": ["Microsoft", "GitHub Copilot", ".NET", "Japan's Digital Agency", "Polymarket", "GPT", "Claude"], "alternates": {"html": "https://wpnews.pro/news/ai-lmc-phase-00-i-just-wanted-to-make-easy-money-with-ai-so-obviously-i-m-now-a", "markdown": "https://wpnews.pro/news/ai-lmc-phase-00-i-just-wanted-to-make-easy-money-with-ai-so-obviously-i-m-now-a.md", "text": "https://wpnews.pro/news/ai-lmc-phase-00-i-just-wanted-to-make-easy-money-with-ai-so-obviously-i-m-now-a.txt", "jsonld": "https://wpnews.pro/news/ai-lmc-phase-00-i-just-wanted-to-make-easy-money-with-ai-so-obviously-i-m-now-a.jsonld"}}