Port React Compiler to Rust

react / react Public Notifications You must be signed in to change notification settings Fork 51k Star 246k Code Issues 839 Pull requests 443 Actions Security and quality 7 Insights Additional navigation options Code Issues Pull requests Actions Security and quality Insights [compiler] Port React Compiler to Rust#36173Mergedmvitousek merged 435 commits intoreact:mainreact/react:mainfrom josephsavona:rust-researchjosephsavona/react:rust-researchCopy head branch name to clipboardJun 9, 2026ConversationCommits435 (435)ChecksFiles changedMerged[compiler] Port React Compiler to Rust#36173mvitousek merged 435 commits intoreact:mainreact/react:mainfrom josephsavona:rust-researchjosephsavona/react:rust-researchCopy head branch name to clipboardConversation josephsavona commented Mar 30, 2026 edited Loading Uh oh! There was an error while loading. Please reload this page. Copy link Copy Markdown Contributor This is an experimental, work-in-progress port of React Compiler to Rust. Key points: We're excited to partner with teams to integrate the Rust version of React Compiler into other tools, like OXC and SWC. If you're interested in working with us on this, the best place to start is by taking a look at the react_compiler_swc and react_compiler_oxc crates. These give you an idea of the API shape that we're thinking of. Note that the conversion from any AST into our HIR is complex, and we can only maintain one version. Hence we've aligned on using a Babel-like AST as our public API. Another key point is that we don't yet implement our own scope analysis (since the TS version of the compiler relied on Babel's scope analysis), so for now we require that the scope data be serialized. It's a denormalized graph, and some metadata has to be stored to associate nodes with scopes. We're open to feedback about the AST and scope representation - we iterated a bit just to get things to work, but it can be more optimal. In terms of the shape of the integration, we anticipate that each integration would have the following: This setup lets us make changes to the integration layer easily within our repo. Feedback appreciated! There was an error while loading. Please reload this page. Joe Savona added 30 commits March 21, 2026 11:17 [rust-compiler] Add HIR function formatting bridge for inner function… … 00c8b83 …s in reactive printer Add HirFunctionFormatter callback to reactive DebugPrinter so FunctionExpression and ObjectMethod values can print their inner HIR functions with full detail. Bridge debug_print.rs formatting into the reactive printer via format_hir_function_into. [rust-compiler] Fix outlined function blank line in reactive printer … 92a03c2 Remove blank line output for unprinted outlined functions that caused Environment section misalignment. 1285/1717 fixtures now pass. [rust-compiler] Fix StoreLocal→LoadLocal conversion in BuildReactiveF… … ccdb7a1 …unction value blocks Port the TS logic that converts StoreLocal to LoadLocal when the last instruction of a value block stores to an unnamed temporary. This fixes identifier/place mismatches in the reactive function output. 1459/1717 fixtures now pass. [rust-compiler] Fix for-loop continue block to use update when present … 679bf84 In BuildReactiveFunction, for-loops should use the update block as the continue target when present, falling back to the test block. Matches TS terminal.update ?? terminal.test pattern. [rust-compiler] Update reactive function plan status … f66b43a BuildReactiveFunction is implemented with 1458/1717 fixtures passing (85%). [rust-compiler] Fix BuildReactiveFunction port fidelity issues … 2259b8b Major fixes to match the TypeScript BuildReactiveFunction behavior: - Add valueBlockResultToSequence for for/for-of/for-in init and for-of test values, which wraps value block results in SequenceExpressions with proper lvalue assignment - Fix for-of continue_block to use init (not test), matching TS scheduleLoop call - Add reachable() checks for if, switch, while, and label terminal fallthroughs - Add loopId checks for all loop types (do-while, while, for, for-of, for-in) to verify loop blocks aren't already scheduled before traversal - Add alternate != fallthrough check for if terminals (matching TS branch semantics) - Fix switch case processing order to reverse (matching TS reverse-iterate-then-reverse) - Fix switch to skip already-scheduled cases instead of pushing None blocks - Fix value block catch-all to not propagate parent fallthrough (TS passes null) - Clean up dead code in value block catch-all Pass rate: 1635/1717 (95.2%). Remaining 82 failures are all earlier-pass issues. [rust-compiler] Port all reactive passes after BuildReactiveFunction … fd8b962 Ported 15 reactive passes and visitor/transform infrastructure from TypeScript to Rust. Includes assertWellFormedBreakTargets, pruneUnusedLabels, assertScopeInstructionsWithinScopes, pruneNonEscapingScopes, pruneNonReactiveDependencies, pruneUnusedScopes, mergeReactiveScopesThatInvalidateT

Port React Compiler to Rust

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