Package

weakmap-polyfill

ECMAScript6 WeakMap polyfill

v2.0.4, 6 Jun 2021MITCommonJSTypes: NonePolyfills and shims

$ npm install weakmap-polyfill

npm GitHub Homepage

Key numbers

As of 25 Sept 2026

Weekly downloads: 1m; +93% over 12 months
Gzip bundle size: -; No Bundlephobia data
Dependencies: 0; Direct, from package.json
Last release: 5 years ago; v2.0.4
GitHub stars: 32; 16 forks
Open issues / PRs: 0 / 7
Contributors: -
Commits, last 52 weeks: 0

Downloads

Last week 2026-09-15 to 2026-09-21

Weekly npm downloads, one point per week, weeks starting 23 Sept 2025 to 15 Sept 2026. The y axis starts at zero.

1,001,085 downloads last week, 4,584,768 in the last month. The 12-month change of +93% compares the average of the last 4 weeks with the first 4 weeks of the series.

Maintenance

Releases, last 12 months: 07 in total
Latest version: 2.0.4, 6 Jun 20215 years ago
First published: 9 Oct 2015
Last push to GitHub: 7 Dec 20221,387 days before the snapshot
Repository archived: No
Open issues: 0
Open pull requests: 7
Commits, last 52 weeks: 0
Dependents on npm: 28

Major versions

v2 first release 2.0.0, 27 Apr 2016
v1 first release 1.0.0, 9 Oct 2015

Recent releases

Version	Published
2.0.4	6 Jun 2021
2.0.3	13 Jan 2021
2.0.2	7 Apr 2020
2.0.1	15 Jan 2020
2.0.0	27 Apr 2016
1.0.1	19 Oct 2015
1.0.0	9 Oct 2015

Compatibility

Module format: CommonJSFrom package.json type, main and exports fields
TypeScript types: None
Node.js engine range: >=8.10.0
Runtimes: -
Unpacked size (npm): 10 kB
Dependencies (0): None

Install

npm install weakmap-polyfill

CDN

jsDelivr: 175.6k requests in 30 days

jsDelivrhttps://cdn.jsdelivr.net/npm/weakmap-polyfill@2.0.4/
unpkghttps://unpkg.com/weakmap-polyfill@2.0.4/
esm.shhttps://esm.sh/weakmap-polyfill@2.0.4

Alternatives

Package	Weekly downloads	Gzip	Last release	Module	Comparison
es5-shim ECMAScript 5 compatibility shims for legacy JavaScript engines	1m	-	4 years ago	CommonJS	-
symbol.prototype.description Spec-compliant shim for Symbol.prototype.description proposal.	599.4k	-	9 months ago	CommonJS	-
array.prototype.with An ESnext spec-compliant `Array.prototype.with` shim/polyfill/replacement that works as far down as ES3.	17.5k	-	2 years ago	CommonJS	-
regexp.escape A robust ES3-compatible polyfill for the `RegExp.escape` proposal - see https://github.com/tc39/proposal-regex-escaping	504k	-	2 years ago	CommonJS	-
set.prototype.difference An ESnext spec-compliant `Set.prototype.difference` shim/polyfill/replacement that works as far down as ES3	144.8k	-	1 year ago	CommonJS	-
set.prototype.intersection An ESnext spec-compliant `Set.prototype.intersection` shim/polyfill/replacement that works as far down as ES3	126k	-	8 months ago	CommonJS	-
array.prototype.foreach An ES spec-compliant `Array.prototype.forEach` shim/polyfill/replacement that works as far down as ES3.	56.4k	-	2 years ago	CommonJS	-
set.prototype.union An ESnext spec-compliant `Set.prototype.union` shim/polyfill/replacement that works as far down as ES3	27.8k	-	2 years ago	CommonJS	-

Sources: npm registry, npm downloads API, GitHub API, jsDelivr. Data fetched 25 Sept 2026.

Indexability: Indexed.