Imagine waking up, opening your trusted VS Code alternative, and finding out that your favorite C/C++ extension has packed its bags and left the building – all thanks to a well-timed update from Microsoft. For many open-source developers and users of VS Code forks such as VS Codium and Cursor, this is not a “dog ate my homework” moment. It’s more like “my landlord padlocked my kitchen and is now selling sandwiches next door.” The C/C++ extension, once the lifeblood for many coding sessions, has stopped working outside of Microsoft's own tightly-walled garden. For some, this change is more than an inconvenience – it’s an existential crisis.
The drama began in early April, when programmers using VS Codium and Cursor noticed – not with a confetti cannon, but an abrupt error message – that the C/C++ extension would not cooperate. This extension, hero of code completion and debugging for C and C++ in the Visual Studio Code universe, suddenly refused to play ball in anything that wasn't official VS Code. Classic move: you can look, but you can’t touch.
Attempts to install the extension in forks like VS Codium wasn't met with a gentle warning, but with the digital equivalent of a “keep out” sign: “The C/C++ extension may be used only with Microsoft Visual Studio, Visual Studio for Mac, Visual Studio Code, Azure DevOps, Team Foundation Server, and successor Microsoft products and services to develop and test your applications.” In other words: if you're not Microsoft, your invitation is revoked. Welcome to a world where software doesn’t just break—it breaks up with you and blames your friends.
The crux? While the extension’s license has always said “Microsoft only,” there wasn’t an explicit check in the code – until v1.24.5, released April 3, 2025, flipped the enforcement switch. For the uninitiated, that meant what was previously an unenforced rule just became a sheriff with actual handcuffs.
A fair number of IT professionals will snicker knowingly here. How many times has ostensibly “open source” software been open only until it’s inconvenient? This is a perennial risk with any tool that straddles the line between genuine open collaboration and a corporate product designed to catch you in a subtle EULA bear trap. You don’t own the gear—you’re just borrowing it, so don’t be surprised when the keys disappear at the first sign of competition.
Cursor’s stated path forward is to lean into the existing community and open source alternatives, bundling these into future versions. On paper, this is both noble and necessary, because sooner or later, reverse proxies and technical sleight-of-hand fall out of fashion – especially when the owner of the ecosystem is a trillion-dollar company with a penchant for litigation.
What does this mean for developers? In the interim, likely a patchwork of extension hunting, switching code completion engines, and some awkward conversations with their build scripts. In the longer term, a possible flourishing of genuinely open and fork-friendly alternatives – assuming the community is fired up enough to maintain momentum.
But let’s not pretend Cursor’s approach was above board. If you’re violating a vendor’s terms—masking your traffic to sneak past the velvet rope—don’t be surprised when you get kicked out of the club and your coat checked for good measure.
In real-world IT, these kinds of abrupt shifts are more than philosophical: they upend developer productivity, disrupt workflows, and make DevOps managers break out their “emergency migration” checklists. The cost? Countless hours spent debugging why an extension stopped, and even more time arguing about blame in the group chat.
If you rely on a tool that can have its functionality torn away by a remote update or licensing change, maybe it’s time to revisit that risk register. For every open source supporter who says, “Just swap to free tools,” there’s a CI/CD pipeline sputtering in the background, wondering why
This is self-preferencing 101. Breathe new, AI-infused life into your own tools while quietly restricting interoperability for any up-and-coming rival. For IT pros, it’s a familiar play: build an enticing garden, then slam the gates before competitors can pick your apples.
Such moves don’t just annoy those running alternative editors; they touch a regulatory nerve. It didn’t take long for at least one developer to fire off a letter to the US Federal Trade Commission, decrying the combination of self-preferencing, forced AI bundling, and the old-fashioned anti-competitive walling-off of rivals.
You can almost envision the Microsoft boardroom chart: “Percentage of world’s code written with Copilot: up. FTC Letters: moderate. Extensions working in VS Codium: declining.”
For well-prepared IT departments and seasoned engineers, this is a cautionary tale. Relying on tools where the vendor can unilaterally yank the rug exposes critical infrastructure to unpredictable risks. Just because something works today doesn’t mean it will tomorrow, and if your IDE bursts into flames over the weekend, your Monday might start with “building the toolchain by hand.”
The real-world implication is grim: depending on closed-source plugins and vendor-operated extension stores can turn essential tooling into a rolling slot machine, with developer productivity at stake on every spin.
For IT leaders, this duality shouldn’t just be a debate topic at the next brown bag – it should be a clause in your risk assessments and architectural decisions. For every project predicated on “community forks,” consider the degree to which your critical functionality rides on someone else’s commercial priorities.
More importantly, what does this mean for the future? If end-to-end open source tools can’t compete on features, developers will be pulled back into proprietary environments, lock-in be damned. VS Code’s popularity surge was built on openness and extensibility, but the balance is delicate. As more core extensions become “Microsoft-only,” the appeal of forks and alternates will diminish, and the monoculture will grow.
That’s a risk not just to your build pipeline, but to the entire ethos of open collaboration in developer communities.
But innovation takes time and resources, and industry inertia is real. Yes, some will argue that the diversity and freedom of open source will ultimately triumph, sprinkling new life into alternative editors. Others, burned by repeated deprecations and surprise lock-outs, will simply shrug and double-down on Microsoft’s official stack—after all, it just works, until it doesn’t.
For the brave, resilient IT pro, every crisis like this is also a lesson: if you want freedom, you have to work for it. Sometimes, that just means writing your own autocomplete engine, even if it autocompletes your tears.
While there’s talk of FTC scrutiny and developer petitions, expect Microsoft to stick to its guns. The lesson for IT professionals and developer teams alike? Hedge your bets, keep a backup plan, and remember: the extension you love today might not be there tomorrow, unless your IDE came straight from Redmond.
As the industry treks deeper into the age of AI-powered code, tighter ecosystems, and subtle self-preferencing, only one thing is certain: old extensions never die, they just find new ways to stop working—usually right before your crunch deadline.
So, give your build scripts a pat. Warn your junior devs that sometimes, the road to productivity is lined with EULAs and traps. And maybe, just maybe, stop to appreciate the open source volunteers tirelessly cobbling together the next generation of free tools—just in time for Microsoft’s next big extension to get homesick.
Source: theregister.com Microsoft subtracts C/C++ extension from VS Code forks
When Extensions Play Favorites
The drama began in early April, when programmers using VS Codium and Cursor noticed – not with a confetti cannon, but an abrupt error message – that the C/C++ extension would not cooperate. This extension, hero of code completion and debugging for C and C++ in the Visual Studio Code universe, suddenly refused to play ball in anything that wasn't official VS Code. Classic move: you can look, but you can’t touch.Attempts to install the extension in forks like VS Codium wasn't met with a gentle warning, but with the digital equivalent of a “keep out” sign: “The C/C++ extension may be used only with Microsoft Visual Studio, Visual Studio for Mac, Visual Studio Code, Azure DevOps, Team Foundation Server, and successor Microsoft products and services to develop and test your applications.” In other words: if you're not Microsoft, your invitation is revoked. Welcome to a world where software doesn’t just break—it breaks up with you and blames your friends.
The crux? While the extension’s license has always said “Microsoft only,” there wasn’t an explicit check in the code – until v1.24.5, released April 3, 2025, flipped the enforcement switch. For the uninitiated, that meant what was previously an unenforced rule just became a sheriff with actual handcuffs.
The Fine Print Bites Back
If you’re getting déjà vu, it might be because this isn’t the first rodeo. The PyLance extension – Microsoft’s darling for Python in VS Code – has been fanatical about the same exclusivity for years, refusing to load in anything not wearing official Microsoft branding. Why did the C/C++ extension finally join this party? Perhaps it saw the popularity of forks and thought, “Not on my watch.”A fair number of IT professionals will snicker knowingly here. How many times has ostensibly “open source” software been open only until it’s inconvenient? This is a perennial risk with any tool that straddles the line between genuine open collaboration and a corporate product designed to catch you in a subtle EULA bear trap. You don’t own the gear—you’re just borrowing it, so don’t be surprised when the keys disappear at the first sign of competition.
Cursor’s Cat-and-Mouse
Cursor, not content to wait for the dust to settle, already had a work-around, according to co-founder and CEO Michael Truell: a temporary fix for users, with promises of an open-source renaissance in future releases. Cursor’s approach up to this point? Use a reverse proxy so that when you fetch extensions, Microsoft’s servers think you’re VS Code proper. This, of course, is not just a clever hack, but the digital equivalent of wearing a fake mustache in a “members only” club. Fun for a while, but bound to annoy the bouncers.Cursor’s stated path forward is to lean into the existing community and open source alternatives, bundling these into future versions. On paper, this is both noble and necessary, because sooner or later, reverse proxies and technical sleight-of-hand fall out of fashion – especially when the owner of the ecosystem is a trillion-dollar company with a penchant for litigation.
What does this mean for developers? In the interim, likely a patchwork of extension hunting, switching code completion engines, and some awkward conversations with their build scripts. In the longer term, a possible flourishing of genuinely open and fork-friendly alternatives – assuming the community is fired up enough to maintain momentum.
But let’s not pretend Cursor’s approach was above board. If you’re violating a vendor’s terms—masking your traffic to sneak past the velvet rope—don’t be surprised when you get kicked out of the club and your coat checked for good measure.
Developers: Caught in the Crossfire
Meanwhile, users of VS Codium and similar forks gaze wistfully at features they once took for granted. With the C/C++ extension gone, the “free as in beer and speech” aspect of these projects takes a big blow. The open source software world often relies on a delicate social contract: vendors tolerate alternative use as long as it doesn’t threaten their market, while users pretend not to notice the fine print. Once that contract breaks, the scramble is on for free and open replacements.In real-world IT, these kinds of abrupt shifts are more than philosophical: they upend developer productivity, disrupt workflows, and make DevOps managers break out their “emergency migration” checklists. The cost? Countless hours spent debugging why an extension stopped, and even more time arguing about blame in the group chat.
If you rely on a tool that can have its functionality torn away by a remote update or licensing change, maybe it’s time to revisit that risk register. For every open source supporter who says, “Just swap to free tools,” there’s a CI/CD pipeline sputtering in the background, wondering why
IntelliSense no longer autocompletes pointer arithmetic with the gusto it once had.Microsoft’s AI Ambitions and the Competitive Quagmire
One cannot overlook the timing: Microsoft, with its Copilot suite and new “Agent Mode,” is angling for dominance in AI-powered coding assistants. Developers note that while Cursor was getting more AI-smarts by leveraging Microsoft’s own extensions, Redmond was simultaneously bolting these features into its own native workflows. The writing was on the wall: “If you want Copilot, you play in our sandbox—no sand for outsiders.”This is self-preferencing 101. Breathe new, AI-infused life into your own tools while quietly restricting interoperability for any up-and-coming rival. For IT pros, it’s a familiar play: build an enticing garden, then slam the gates before competitors can pick your apples.
Such moves don’t just annoy those running alternative editors; they touch a regulatory nerve. It didn’t take long for at least one developer to fire off a letter to the US Federal Trade Commission, decrying the combination of self-preferencing, forced AI bundling, and the old-fashioned anti-competitive walling-off of rivals.
You can almost envision the Microsoft boardroom chart: “Percentage of world’s code written with Copilot: up. FTC Letters: moderate. Extensions working in VS Codium: declining.”
The License You Didn’t Read (But Should Have)
Here’s the rub: Microsoft’s extensions for VS Code have, for years, carried a license forbidding use outside of Microsoft-branded products. No subtext, no ambiguity. The alarming part isn’t the enforcement but how long it went unenforced. Developers got used to a kind of “don’t ask, don’t tell” ecosystem. Suddenly, it’s “don’t even try.”For well-prepared IT departments and seasoned engineers, this is a cautionary tale. Relying on tools where the vendor can unilaterally yank the rug exposes critical infrastructure to unpredictable risks. Just because something works today doesn’t mean it will tomorrow, and if your IDE bursts into flames over the weekend, your Monday might start with “building the toolchain by hand.”
The real-world implication is grim: depending on closed-source plugins and vendor-operated extension stores can turn essential tooling into a rolling slot machine, with developer productivity at stake on every spin.
The Open Source Dilemma—Freedom With Strings Attached
The situation exposes an age-old tension in software: open source codebases with proprietary plugins. VS Code itself is open source under the MIT license, but the best features—like C/C++ language support—are locked in extension binaries with their own EULA. It’s a bait-and-switch scenario dressed up in collaborative clothing.For IT leaders, this duality shouldn’t just be a debate topic at the next brown bag – it should be a clause in your risk assessments and architectural decisions. For every project predicated on “community forks,” consider the degree to which your critical functionality rides on someone else’s commercial priorities.
More importantly, what does this mean for the future? If end-to-end open source tools can’t compete on features, developers will be pulled back into proprietary environments, lock-in be damned. VS Code’s popularity surge was built on openness and extensibility, but the balance is delicate. As more core extensions become “Microsoft-only,” the appeal of forks and alternates will diminish, and the monoculture will grow.
That’s a risk not just to your build pipeline, but to the entire ethos of open collaboration in developer communities.
Silver Linings and Community Lightning
Yet, for all the gloom, there’s a silver lining—or at least, a determined community response. Cursor, for example, is speeding toward open-source alternatives. The VS Codium user base has already started benchmarking and patching new plugins. This could, in a perverse way, stimulate innovation and energy around truly open extensions, breaking the cycle of dependency on Microsoft’s offerings.But innovation takes time and resources, and industry inertia is real. Yes, some will argue that the diversity and freedom of open source will ultimately triumph, sprinkling new life into alternative editors. Others, burned by repeated deprecations and surprise lock-outs, will simply shrug and double-down on Microsoft’s official stack—after all, it just works, until it doesn’t.
For the brave, resilient IT pro, every crisis like this is also a lesson: if you want freedom, you have to work for it. Sometimes, that just means writing your own autocomplete engine, even if it autocompletes your tears.
Conclusions: Monoculture Blues and Tech Darwinism
In the end, Microsoft’s decision to actively enforce extension exclusivity exposes uncomfortable truths about the nature of open source in a corporate-dominated cloud world. Perhaps your code is only as open as the binary blobs you depend on—and if your vendor is chasing AI marketshare, your forked editor might be collateral damage.While there’s talk of FTC scrutiny and developer petitions, expect Microsoft to stick to its guns. The lesson for IT professionals and developer teams alike? Hedge your bets, keep a backup plan, and remember: the extension you love today might not be there tomorrow, unless your IDE came straight from Redmond.
As the industry treks deeper into the age of AI-powered code, tighter ecosystems, and subtle self-preferencing, only one thing is certain: old extensions never die, they just find new ways to stop working—usually right before your crunch deadline.
So, give your build scripts a pat. Warn your junior devs that sometimes, the road to productivity is lined with EULAs and traps. And maybe, just maybe, stop to appreciate the open source volunteers tirelessly cobbling together the next generation of free tools—just in time for Microsoft’s next big extension to get homesick.
Source: theregister.com Microsoft subtracts C/C++ extension from VS Code forks
