HTTP/2 200
date: Mon, 13 Oct 2025 10:17:05 GMT
content-type: text/html; charset=utf-8
vary: X-PJAX, X-PJAX-Container, Turbo-Visit, Turbo-Frame, X-Requested-With,Accept-Encoding, Accept, X-Requested-With
etag: W/"b4fdb1f07315f47e566ed023a1e697a0"
cache-control: max-age=0, private, must-revalidate
strict-transport-security: max-age=31536000; includeSubdomains; preload
x-frame-options: deny
x-content-type-options: nosniff
x-xss-protection: 0
referrer-policy: origin-when-cross-origin, strict-origin-when-cross-origin
content-security-policy: default-src 'none'; base-uri 'self'; child-src github.githubassets.com github.com/assets-cdn/worker/ github.com/assets/ gist.github.com/assets-cdn/worker/; connect-src 'self' uploads.github.com www.githubstatus.com collector.github.com raw.githubusercontent.com api.github.com github-cloud.s3.amazonaws.com github-production-repository-file-5c1aeb.s3.amazonaws.com github-production-upload-manifest-file-7fdce7.s3.amazonaws.com github-production-user-asset-6210df.s3.amazonaws.com *.rel.tunnels.api.visualstudio.com wss://*.rel.tunnels.api.visualstudio.com github.githubassets.com objects-origin.githubusercontent.com copilot-proxy.githubusercontent.com proxy.individual.githubcopilot.com proxy.business.githubcopilot.com proxy.enterprise.githubcopilot.com *.actions.githubusercontent.com wss://*.actions.githubusercontent.com productionresultssa0.blob.core.windows.net/ productionresultssa1.blob.core.windows.net/ productionresultssa2.blob.core.windows.net/ productionresultssa3.blob.core.windows.net/ productionresultssa4.blob.core.windows.net/ productionresultssa5.blob.core.windows.net/ productionresultssa6.blob.core.windows.net/ productionresultssa7.blob.core.windows.net/ productionresultssa8.blob.core.windows.net/ productionresultssa9.blob.core.windows.net/ productionresultssa10.blob.core.windows.net/ productionresultssa11.blob.core.windows.net/ productionresultssa12.blob.core.windows.net/ productionresultssa13.blob.core.windows.net/ productionresultssa14.blob.core.windows.net/ productionresultssa15.blob.core.windows.net/ productionresultssa16.blob.core.windows.net/ productionresultssa17.blob.core.windows.net/ productionresultssa18.blob.core.windows.net/ productionresultssa19.blob.core.windows.net/ github-production-repository-image-32fea6.s3.amazonaws.com github-production-release-asset-2e65be.s3.amazonaws.com insights.github.com wss://alive.github.com wss://alive-staging.github.com api.githubcopilot.com api.individual.githubcopilot.com api.business.githubcopilot.com api.enterprise.githubcopilot.com; font-src github.githubassets.com; form-action 'self' github.com gist.github.com copilot-workspace.githubnext.com objects-origin.githubusercontent.com; frame-ancestors 'none'; frame-src viewscreen.githubusercontent.com notebooks.githubusercontent.com; img-src 'self' data: blob: github.githubassets.com media.githubusercontent.com camo.githubusercontent.com identicons.github.com avatars.githubusercontent.com private-avatars.githubusercontent.com github-cloud.s3.amazonaws.com objects.githubusercontent.com release-assets.githubusercontent.com secured-user-images.githubusercontent.com/ user-images.githubusercontent.com/ private-user-images.githubusercontent.com opengraph.githubassets.com marketplace-screenshots.githubusercontent.com/ copilotprodattachments.blob.core.windows.net/github-production-copilot-attachments/ github-production-user-asset-6210df.s3.amazonaws.com customer-stories-feed.github.com spotlights-feed.github.com objects-origin.githubusercontent.com *.githubusercontent.com; manifest-src 'self'; media-src github.com user-images.githubusercontent.com/ secured-user-images.githubusercontent.com/ private-user-images.githubusercontent.com github-production-user-asset-6210df.s3.amazonaws.com gist.github.com; script-src github.githubassets.com; style-src 'unsafe-inline' github.githubassets.com; upgrade-insecure-requests; worker-src github.githubassets.com github.com/assets-cdn/worker/ github.com/assets/ gist.github.com/assets-cdn/worker/
server: github.com
content-encoding: gzip
accept-ranges: bytes
set-cookie: _gh_sess=VODYSam0L9YgSNfzXHJicIzFIFDUFkD7TpsfddTXl05DjftvRUCdCujqPMEY0rUCMkey3Wc2nfzaf7gskmvJr6xxBUXMB66A9FODLEW6icK7ywviROstZ6ix3f6qCnhrSMaTSe45JBRQ%2BHWVWgg9zpzLHjlsk5KroE58NgP7MfXtt5D7YQT1Au6g8Rsy316kaP%2Bqes5HYeY24VACZ1vUsYizLkaTMd7nUKOODdL0dk3iL1Zl8c325t6Jw8ys6YrhlGk26btvEwKnKY5Ew3ps0g%3D%3D--G8cjWSwAUrb7R%2FBQ--bZ9s8%2B542yTXI7rgx1kiTA%3D%3D; Path=/; HttpOnly; Secure; SameSite=Lax
set-cookie: _octo=GH1.1.47075598.1760350625; Path=/; Domain=github.com; Expires=Tue, 13 Oct 2026 10:17:05 GMT; Secure; SameSite=Lax
set-cookie: logged_in=no; Path=/; Domain=github.com; Expires=Tue, 13 Oct 2026 10:17:05 GMT; HttpOnly; Secure; SameSite=Lax
x-github-request-id: EE3E:2A5D20:134FA1F:1896903:68ECD1A1
ECMAScript Shims · GitHub
ECMAScript Shims
A community host for shims and polyfills that are compliant to EcmaScript specs.
Pinned
Loading
ECMAScript 5 compatibility shims for legacy (and modern) JavaScript engines
JavaScript
7.1k
893
ECMAScript spec-compliant polyfill/shim for `globalThis`.
JavaScript
155
13
ES Proposal spec-compliant shim for Promise.prototype.finally
JavaScript
138
9
ES Proposal spec-compliant shim for Promise.allSettled
JavaScript
97
10
API contract, and rudimentary tests, for modules that conform to the *es-shim API*
JavaScript
80
4
Repositories
Showing 10 of 166 repositories
es-shims/es6-shim’s past year of commit activity
JavaScript
683
MIT
398
0
0
Updated Oct 9, 2025
Map.groupBy
Public
An ESnext spec-compliant `Map.groupBy` shim/polyfill/replacement that works as far down as ES3.
es-shims/Map.groupBy’s past year of commit activity
JavaScript
1
MIT
0
1
0
Updated Sep 12, 2025
es-shims/String.prototype.replaceAll’s past year of commit activity
JavaScript
36
MIT
2
1
0
Updated Sep 12, 2025
error-cause
Public
An ES-spec-compliant shim/polyfill/replacement for the `.cause` property on all Error types that works as far down as ES3
es-shims/error-cause’s past year of commit activity
JavaScript
18
MIT
4
1
0
Updated Sep 12, 2025
es-shim-api
Public
API contract, and rudimentary tests, for modules that conform to the *es-shim API*
es-shims/es-shim-api’s past year of commit activity
JavaScript
80
MIT
4
1
0
Updated Sep 9, 2025
Error.isError
Public
An ESnext spec-compliant `Error.isError` shim/polyfill/replacement that works as far down as ES3.
es-shims/Error.isError’s past year of commit activity
JavaScript
2
MIT
2
2
1
Updated Jul 24, 2025
String.prototype.lastIndexOf
Public
An ES-spec-compliant `String.prototype.lastIndexOf`shim/polyfill/replacement that works as far down as ES3.
es-shims/String.prototype.lastIndexOf’s past year of commit activity
JavaScript
0
MIT
1
1
0
Updated Jul 24, 2025
es-shims/WeakMap.prototype.getOrInsertComputed’s past year of commit activity
JavaScript
0
MIT
0
1
0
Updated Jul 16, 2025
es-shims/String.prototype.codePointAt’s past year of commit activity
JavaScript
1
MIT
6
0
0
Updated Jul 14, 2025
es-arraybuffer-base64
Public
An ES-spec-compliant shim/polyfill/replacement for ArrayBuffer base64 methods that works as far down as ES3
es-shims/es-arraybuffer-base64’s past year of commit activity
JavaScript
9
MIT
2
1
0
Updated Jul 7, 2025
Most used topics
Loading…
You can’t perform that action at this time.