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npm · #374 most downloaded on npm
zlib port to javascript - fast, modularized, with browser support
Last release 22 days ago
12 Sep 2026
Ships unpredictably
gaps range from 2 weeks to 3.6 years
Nearly every release is documented
notes for 33 of 35 stable releases
Nothing withdrawn
no release was ever pulled
13 years old
35 releases · first in 2014
Port missed upstream zlib fix for block type selection with Z_FIXED, avoiding fixed blocks when stored blocks would be smaller, #316.
Z_FIXED,
avoiding fixed blocks when stored blocks would be smaller, #316.Narrow Uint8Array type to ArrayBuffer only
One column per quarter.
.onStart() hooks for advanced stream setup.
zlib API exports..onStart() hooks for advanced stream setup.import * as pako from 'pako' instead of
default import if you need the whole API as an object.package.json for supported entry points.legacyHash default is now false. Binary output is now compatible with
nodejs by default.dictionary option now accepts only Uint8Array / ArrayBuffer
(no String anymore)..onEnd() now only assembles output chunks into result, and no longer sets
the err / msg fields.TextEncoder / TextDecoder for string conversion. Removed shims.{ to: 'string' }) with { toText: true }) for UTF-8 text output in
high-level helpers (inflate, inflateRaw, ungzip).dist/ on publish instead of keeping generated bundles in git.Inflate.push() after stream end returns the decode result, not always
false.import pako from 'pako' is no longer supported.{ to: 'string' }) option from the streaming Inflate class. It now always
emits byte chunks.Inflate. Use .onStart() with
zlibInflateGetHeader() to read gzip metadata.dist/ bundles from repository.Alternate deflate hash (ANZAC++) - for nodejs zlib compatibility. A nice bonus ~ 40% speed boost.
legacyHash (default: true) deflate option, to switch between original zlib
and nodejs binary-compatible output.inflateReset (multistream/bgzip), #139.Updated comments in tree.js for Babel compatibility, #262.
zlib 1.2.12.tree.js for Babel compatibility, #262.Use TextEncoder and TextDecoder if available, #228.
Add all files explicit to package exports (since behaviour changed after adding .export field)
### Fixed - Fix esm build named exports.
Changed esm build .js => .mjs to fix node.js import.
.js => .mjs to fix node.js import.module entry in package.json for some bundlers.Removed binary strings and Array support.
Array support..set(), .subarray()).Inflate & Deflate instance create without new.Inflate.push() no longer needs second param (end is auto-detected)..constants./dist./dist folder changed.Fix tests in node.js v12+, #179.
### Fixed - Fix minified version, #161.
Fix new Buffer() warning, #154.
new Buffer() warning, #154.Fix raw inflate with dictionary, #155.
Fixed RangeError in Crome 72, #150.
Improve @std/esm compatibility.
Maintenance. More formal zlib attribution and related changes, #93. Thanks to @bastien-roucaries for the help.
zlib attribution and related
changes, #93. Thanks to @bastien-roucaries for the help.Make sure err.message is filled on throw.
err.message is filled on throw.Maintenance: re-release to properly display latest version in npm registry and badges. Because npm publish timestamp used instead of versions.
npm publish timestamp used instead of versions.Fixed nasty bug in deflate (wrong d_buf offset), which could cause broken data in some rare cases.
d_buf offset), which could cause
broken data in some rare cases.Added dictionary support. Thanks to @dignifiedquire.
Maintenance release (semver, coding style).
Nothing published for this version
Fixed regression after 0.2.4 for edge conditions in inflate wrapper (#65). Added more tests to cover possible cases.
Added Z_SYNC_FLUSH support. Thanks to @TinoLange.
### Added - Allow ArrayBuffer input.
Workaround for Chrome 38.0.2096.0 script parser bug, #30.
Fixed bug in inflate wrapper, #29
Maintenance release, dependencies update.
Fixed iOS 5.1 Safari issue with apply(typed_array), #26.
apply(typed_array), #26.Fixed collision on switch dynamic/fixed tables.
Added custom gzip headers support.
### Fixed - Bugfixes for inflate/deflate.
[3.0.0]: https://github.com/nodeca/pako/compare/2.2.0...3.0.0 [2.2.0]: https://github.com/nodeca/pako/compare/2.1.0...2.2.0 [2.1.0]: https://github.co
Nothing published for this version
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