Claude’s code: Anthropic leaks source code for AI software engineering tool

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Anthropic accidentally released part of the internal source code for its AI-powered coding assistant, Claude Code, due to “human error”, the company said on Tuesday,An internal-use file mistakenly included in a software update pointed to an archive containing nearly 2,000 files and 500,000 lines of code, which were quickly copied to developer platform GitHub,A post on X sharing a link to the leaked code had more than 29m views early on Wednesday, and a rewritten version of the source code quickly became GitHub’s fastest-ever downloaded repository,Anthropic issued copyright takedown requests to try to contain the code’s spread,Within the code, users spotted blueprints for a Tamagotchi-esque coding assistant and an always-on AI agent, per the Verge.

“Earlier today, a Claude Code release included some internal source code,No sensitive customer data or credentials were involved or exposed,” an Anthropic spokesperson said,“This was a release packaging issue caused by human error, not a security breach,”The exposed code was related to the tool’s internal architecture but did not contain confidential data from Claude, the underlying AI model by Anthropic,Claude Code’s source code was partially known, as the tool had been reverse-engineered by independent developers.

An earlier version of the assistant had its source code exposed in February 2025.Claude Code has emerged as a key product for Anthropic, as the company’s paid subscriber base continues to grow.TechCrunch reported last week that paid subscriptions have more than doubled this year, per an Anthropic spokesperson.Anthropic’s Claude chatbot also received a popularity boost amid the CEO Dario Amodei’s tussle with the Pentagon; Claude climbed to the top spot of Apple’s chart of top free apps in the US just more than a month ago.Amodei had refused to back down on red lines around the use of his company’s technology for mass surveillance and fully autonomous weapons.

This is the second time that Anthropic has had a data leak in recent weeks.Fortune previously reported on a separate breach and noted that the company was storing thousands of internal files on publicly accessible systems.That included a draft of a blog post that referred to an upcoming model known as “Mythos” and “Capybara”.Some experts worry the leaks suggest internal security vulnerabilities within Anthropic.That could be particularly troubling for a company focused on AI safety.

The leaks could also help competitors, like OpenAI and Google, better understand how Claude Code’s AI system works.The Wall Street Journal reported that the most recent leak included commercially sensitive information, such as tools and instructions for getting its AI models to work as coding agents.The latest breach comes weeks after the US government designated Anthropic as a supply chain risk; Anthropic is fighting those allegations in court.Last week, a US district judge granted a temporary injunction to block the designation.
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Oats, sardines and crisps: emergency foods to stockpile – and why you should share them

People should have an emergency stockpile of food in their homes in case conflicts, extreme weather or cyber-attacks shut down supplies, leading UK experts have told the Guardian.In an ever more turbulent world, they say it is essential to choose long-life items that can be eaten without cooking – think tinned beans, vegetables and fish, rice crackers, and oats that can be soaked. But it is also important to choose items you actually like to eat, and some treats such as chocolate or crisps to keep your spirits up. You will also need water – lots of it – not just to drink but for washing too.Perhaps the most surprising advice is to be prepared to share your stockpile with neighbours

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Reese’s chocolate heir accuses Hershey of altering recipes: ‘It wasn’t real peanut butter’

The grandson of HB Reese, the inventor of Reese’s Peanut Butter Cups, has accused the chocolate giant Hershey of faking a pledge to investors to switch back the recipes of its popular products – including KitKat – to the original milk and dark chocolate ones.A confectionery-focused dust-up between Brad Reese and the $42bn Pennsylvania-based company began in February when Reese, 70, accused the company of “quietly replacing” the ingredients – or “architecture” – in his grandfather’s invention with cheaper “compound coatings” and “peanut-butter-style crèmes”.At a recent Hershey investor conference, the company said it would change about 3% of select products to the original recipes but maintained it had never altered the renowned Reese’s Peanut Butter Cups.The company’s chief growth officer, Stacy Taffet, said Hershey was “transitioning our sweets portfolio to colors from natural sources, and ensuring that all Hershey’s and Reese’s offerings are consistent with their brand’s classic milk and dark chocolate recipes”. The changes are planned to come into effect by next year

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Put away the Aperol and raise a glass to Hugo spritz, the drink of the summer

Pub gardens and bar terraces have been awash with a sea of orange in recent years as Italy’s love of Aperol spritz spread to the UK. But this year the cocktail’s cousin, a Hugo spritz, will be the drink of the summer, according to supermarkets and bars.It is already being served across the country, including at Sea Containers on the banks of the Thames and Mayfair’s swanky Claridge’s hotel in London, 20 Stories bar in Manchester and the Bridge Tavern in Newcastle. Wetherspoons has the cocktail on its menu nationwide.“In the past year, we have noted that there has been a wider shift among our guests towards drinks with lower alcohol percentages, particularly during the day – a Hugo spritz fits rather neatly into this space,” said George Raju, director of bars at Claridge’s

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Helen Goh’s recipe for ricotta, rum and raisin cake | The sweet spot

This is a cake for the long, ambling tail-end of an Easter lunch. It’s gently scented with orange and vanilla, lightened by ricotta, and studded with rum-soaked raisins that bring bursts of sweetness to each slice. Ideally, they’d be soaked overnight to plump them into something luscious, but if time gets away from you, take a shortcut: put the raisins and rum in a microwave-safe bowl, zap for 20–30 seconds, then leave to cool and absorb. The chocolate glaze is optional; on days when you want something simpler (or lighter), a generous sifting of icing sugar is all this cake needs. Serve with a small glass of grappa or something similarly warming for a quietly perfect way to bring a feast to a close

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Cocoa-crazy: chocolate-infused liqueurs deserve their own moment

Among my minor childhood traumas was the time my dad returned from a business trip to Belgium with a smart box of assorted chocolates (cue tiny violins). Expecting caramel, I bit into a truffle and was met by an explosion of very boozy liqueur. The box seemed to be an exciting change from the usual duty-free Toblerone, but after this incident, truffle assortments have always struck me as deeply unsafe. (I have tried liqueur-filled chocolates since, but still remain flummoxed by them.)The Guardian’s journalism is independent

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Baked cheesy smoked haddock and lemon icebox pudding: Henry Harris’ alternative Easter lunch

Sometimes all you want is a hot, bubbling dish and a spoon, and for me today’s cheesy haddock is that dish – a 15-minute supper to be enjoyed in front of the telly with a salad or a large bowl of hot buttered peas. Add a lemony, biscuity iced dessert, and you have a light, very easy and enjoyable supper that’s almost the perfect close to a long Easter weekend.Choose your smoked haddock carefully: you want large, thick fillets of undyed fish. Stating the obvious, here, but a good fishmonger will have this; a supermarket never. The creme fraiche must be a French, naturally soured cream, too, becausethe cheaper English versions coagulate when heat is applied, resulting in an unpleasant, watery gunk