ECMAScript Modernization

Modernize JavaScript and TypeScript code to yearly ECMAScript standard APIs. The outcome is a codebase that is clearer, safer, smaller, and aligned with the newest runtime the project can honestly support.

Pick The Edition

• ES2016: load references/es2016.md for Array.prototype.includes and exponentiation.
• ES2017: load references/es2017.md for async/await, Object.values, Object.entries, descriptors, string padding, and trailing commas.
• ES2018: load references/es2018.md for object rest/spread, async iteration, Promise.prototype.finally, and RegExp improvements.
• ES2019: load references/es2019.md for flat, flatMap, Object.fromEntries, string trimming, and optional catch binding.
• ES2020: load references/es2020.md for optional chaining, nullish coalescing, Promise.allSettled, dynamic import, globalThis, BigInt, and matchAll.
• ES2021: load references/es2021.md for logical assignment, Promise.any, replaceAll, numeric separators, and weak references.
• ES2022: load references/es2022.md for class fields, private fields, top-level await, Error.cause, Object.hasOwn, .at, and RegExp match indices.
• ES2023: load references/es2023.md for copy-on-write arrays, findLast, findLastIndex, symbols as WeakMap keys, and hashbang grammar.
• ES2024: load references/es2024.md for Object.groupBy, Map.groupBy, Promise.withResolvers, RegExp /v, well-formed strings, Atomics.waitAsync, and resizable/transferable buffers.
• ES2025: load references/es2025.md for iterator helpers, Set methods, import attributes and JSON modules, RegExp.escape, inline RegExp modifiers, Promise.try, and float16 APIs.

When the requested edition is unclear, inspect the code pattern first and load the matching reference. Load multiple year references only when the task spans multiple editions.