{"version":"2.1.319","anchor":"bun-runtime-refuses-nodevm-contexts-it-cannot-recognize","canonical_anchor":"bun-runtime-refuses-nodevm-contexts-it-cannot-recognize","heading":"Claude Code refuses an unsafe isolated code context under some Bun runtimes","tier":"notice","area":"Runtime","scope":"individual","heads_up":true,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.319\/e\/bun-runtime-refuses-nodevm-contexts-it-cannot-recognize","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.319","markdown":"### Claude Code refuses an unsafe isolated code context under some Bun runtimes\n\nIf the Bun runtime cannot recognise an isolated code context, Claude Code now stops rather than risk bypassing sandbox checks\n\n**What**\n\nBun is the JavaScript runtime, the engine, that can run Claude Code. Claude Code sometimes runs code in a separate isolated context. If the Bun it is running under cannot recognise such a context, Claude Code now refuses to create it. The error says sandbox checks could otherwise be bypassed and tells you to run Claude Code's native build, whose runtime can recognise it.\n\n**Why**\n\nThis closes a gap in the sandbox, the protective boundary around what code can do, when Claude Code is not run as its native build.\n\n- Area: Runtime\n- Tier: You'll notice\n- Useful: 2\/5\n- Signal: 3\/5\n- Scope: individual\n- Heads-up: yes"}