Lodash Migration & Compat Guide

Guide users through migrating lodash to es-toolkit and understanding the strict vs compat APIs, grounded in actual source code.

Input

$ARGUMENTS — Lodash code to migrate, specific function names, or a question about strict vs compat.

Core Concepts

es-toolkit (strict): Opinionated, simplified API for the 85% use case. Smaller bundle, may differ from lodash in edge cases by design. New functions are added here.

es-toolkit/compat: Aims for full lodash test compatibility within a defined scope. See docs/compatibility.md for out-of-scope behaviors (e.g., implicit type conversions, prototype modifications).

Why source-first matters

The only reliable way to know the difference between strict and compat is to read the actual implementation. Never guess — always verify from source.

Workflow