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crates.io · #1505 most downloaded on crates.io
Rust parser for the WebAssembly Text format, WAT
Last release 6 days ago
02 Oct 2026
Ships on a steady schedule
a new release about every 2 weeks
Some releases are documented
notes for 16 of the last 60 stable releases
2 versions withdrawn
withdrawn after publishing
10 years old
174 releases · first in 2016
Switch to ignoring semver-minor updates by @alexcrichton in #2710
start section by @alexcrichton in #2722read_var_s33 and handling in component defined types by @alexcrichton in #2723map by @alexcrichton in #2725wasmparser by @alexcrichton in #2721Full Changelog: v1.260.0...v1.261.0
One column per quarter.
perf: optimize OperatorsReader::skip_const_expr by @dishmaker in #2653
OperatorsReader::skip_const_expr by @dishmaker in #2653ComponentBuilder::start() by @zacharywhitley in #2657name section by @alexcrichton in #2659MAX_WASM_INSTANCES to 4_096 by @noobHappylife in #2661{stream,future}.forward canon builtins by @rvolosatovs in #2614wasm-tools component new for page-size-1 memory by @chenyan2002 in #2666deps path by @celarye in #2677wast by @alexcrichton in #2674wast by @alexcrichton in #2679% labels by @Lstarsky0 in #2678br_on_cast{,_fail} accepting continuation types by @alexcrichton in #2683future.write by @alexcrichton in #2690array.new-fixed in unreachable code by @alexcrichton in #2688__wasm_call_ctors and __wasm_apply_data_relocs by @Lstarsky0 in #2699Full Changelog: v1.259.0...v1.260.0
Refactor name resolution of components in the text format by @alexcrichton in #2621
cancellable immediate from component model intrinsics by @alexcrichton in #2630cm-implements and cm-map features by default by @alexcrichton in #2634deinline_import_export by @alexcrichton in #2647Full Changelog: v1.258.0...v1.259.0
[1.258.x] Fix environment tag for maybe-trigger-tag job by @alexcrichton in #2747
Full Changelog: v1.258.2...v1.258.3
Document that --realloc-via-memory-grow only affects adapters by @Lstarsky0 in #2613
--realloc-via-memory-grow only affects adapters by @Lstarsky0 in #2613{stream,future}.cancel-{read,write} by @rvolosatovs in #2615wit-dylib by @alexcrichton in #2617__wasi_init_tp import by @alexcrichton in #2616Full Changelog: v1.257.1...v1.258.0
Restore the default for component new --merge-imports-based-on-semver by @Lstarsky0 in #2611
component new --merge-imports-based-on-semver by @Lstarsky0 in #2611Full Changelog: v1.257.0...v1.257.1
Enable wide-arithmetic/compact-imports by default by @alexcrichton in #2593
map support to wit-dylib by @dicej in #2594return_call_ref by @alexcrichton in #2598wasm-tools compose print no output by @alexcrichton in #2601wit-component into one by @alexcrichton in #2600__wasm_init_task to a "task hook" by @alexcrichton in #2603__wasm_task_hook for realloc options by @alexcrichton in #2605cabi_realloc in the main module by @alexcrichton in #2606Full Changelog: v1.256.0...v1.257.0
Import a data symbol for libdl.so by @alexcrichton in #2588
libdl.so by @alexcrichton in #2588ResolveErrorKind by @mkatychev in #2589Full Changelog: v1.255.0...v1.256.0
Fix generating deeply nested WIT types in wit-smith by @alexcrichton in #2576
wit-smith by @alexcrichton in #2576wit_component::linking by @dicej in #2581__wasm_init_task more than once in init module by @dicej in #2582__wasm_{g,s}et_{tls_base,stack_pointer} in wit-component by @alexcrichton in #2584thread.new-indirect intrinsic calls by @dicej in #2585Full Changelog: v1.254.0...v1.255.0
Pin Rust toolchain in older branch versions by @alexcrichton in #2695
Full Changelog: v1.254.0...v1.254.2
Reject out-of-range NaN payloads and bare type-index value types by @vouillon in #2563
(on $t switch) handler by @vouillon in #2564wasm-wave by @alexcrichton in #2566wasm-smith by @alexcrichton in #2569realloc for async-lowered results-with-pointers by @alexcrichton in #2572__wasm_init_task for _initialize hook by @alexcrichton in #2574Full Changelog: v1.253.0...v1.254.0
Limit the element count of fixed-length lists by @eyupcanakman in #2537
KebabStr to not require unsafe code by @alexcrichton in #2548resource.drop async by @alexcrichton in #2552versionsuffix and external-id by @alexcrichton in #2555SourceMap::resolve_span for resolving global span locations by @PhoebeSzmucer in #2559external-id on more items by @alexcrichton in #2558Full Changelog: v1.252.0...v1.253.0
Converge to unicode-ident and remove unicode-xid dependency by @Marcondiro in #2535
CM_ASYNC feature by default by @alexcrichton in #2539Full Changelog: v1.251.0...v1.252.0
wit-parser: don't panic on a re-exported imported resource by @eyupcanakman in #2526
Full Changelog: v1.250.0...v1.251.0
addr2line: echo input addresses back as given instead of hex by @eyupcanakman in #2521
waitables by @michael-weigelt in #2514wasm-smith's Wasm GC support by @fitzgen in #2523Full Changelog: v1.249.0...v1.250.0
Add more snapshots for feature gate paths and fix a panic on @SInCE include by @PhoebeSzmucer in #2510
async types when lift/lower uses async by @alexcrichton in #2512(implements "...") component name support by @ricochet in #2453wasm-smith: Consume fuel for implicit loops by @fitzgen in #2519Full Changelog: v1.248.0...v1.249.0
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