Migrating to El Form

El Form deliberately keeps a familiar register / handleSubmit / formState shape, so moving from React Hook Form or Formik is usually a small, mechanical change rather than a rewrite. This guide covers what maps directly, what's different, and the handful of things worth knowing.

El Form's philosophy is to take the best ideas from these libraries and simplify them — not to be a drop-in clone. Where the API differs, it's because the El Form way is meant to be simpler or more flexible, not just different. See Philosophy.

From React Hook Form

The mental model is almost identical

// React Hook Form
import { useForm } from "react-hook-form";
import { zodResolver } from "@hookform/resolvers/zod";

const {
  register,
  handleSubmit,
  formState: { errors },
} = useForm({ resolver: zodResolver(schema) });

<form onSubmit={handleSubmit(onValid)}>
  <input {...register("email")} />
  {errors.email && <span>{errors.email.message}</span>}
</form>;

// El Form — no resolver package needed; pass the schema directly
import { useForm } from "el-form-react-hooks";

const { register, handleSubmit, formState } = useForm({
  validators: { onSubmit: schema },
});

<form onSubmit={handleSubmit(onValid)}>
  <input {...register("email")} />
  {formState.errors.email && <span>{formState.errors.email}</span>}
</form>;

What's the same

• register("name") returns spreadable props (name, value/checked, onChange, onBlur, ref) and supports nested paths like register("address.city") and array paths like register("items.0.name").
• handleSubmit(onValid, onError?) validates, then calls your handler.
• formState exposes errors, isDirty, isValid, isSubmitting, touched.
• setValue, reset, watch, trigger, setFocus, getFieldState all exist.
• useFieldArray exists for dynamic lists (see Array Fields).
• Focus-on-error is on by default (shouldFocusError), just like RHF.

What's different

React Hook Form	El Form	Why
resolver: zodResolver(schema)	validators: { onChange | onBlur | onSubmit: schema }	No resolver adapter package — pass Zod/Yup/Valibot or a plain function directly, and choose when it runs per event.
errors.email?.message	formState.errors.email (a string)	El Form errors are plain strings, not objects.
mode: "onChange"	validators: { onChange: schema } (or validateOn)	Validation timing is expressed by which event key you put the validator under.
useFieldArray({ control, name })	useFieldArray({ name }) (inside FormProvider) or useFieldArray({ name, form })	No control object — use context or pass form.
field.id from useFieldArray	field.id (same idea; configurable via keyName)	Stable React keys for rows; see Array Fields.

Step-by-step

1. Replace useForm({ resolver: zodResolver(schema) }) with useForm({ validators: { onSubmit: schema } }) (or onChange/onBlur for live validation). Drop @hookform/resolvers.
2. Read errors as formState.errors.field (a string) instead of errors.field.message.
3. Leave your {...register("field")} spreads as-is.
4. Swap useFieldArray({ control, name }) for useFieldArray({ name }) and render rows with key={field.id}.

From Formik

// Formik
import { useFormik } from "formik";

const formik = useFormik({
  initialValues: { email: "" },
  validationSchema: yupSchema,
  onSubmit: (values) => save(values),
});

<form onSubmit={formik.handleSubmit}>
  <input
    name="email"
    value={formik.values.email}
    onChange={formik.handleChange}
    onBlur={formik.handleBlur}
  />
  {formik.touched.email && formik.errors.email && <span>{formik.errors.email}</span>}
</form>;

// El Form
import { useForm } from "el-form-react-hooks";

const { register, handleSubmit, formState } = useForm({
  defaultValues: { email: "" },
  validators: { onChange: schema }, // Zod, Yup, or Valibot all work
});

<form onSubmit={handleSubmit((values) => save(values))}>
  <input {...register("email")} />
  {formState.touched.email && formState.errors.email && (
    <span>{formState.errors.email}</span>
  )}
</form>;

Formik → El Form cheat sheet

Formik	El Form
useFormik(...)	useForm(...)
initialValues	defaultValues
validationSchema: yupSchema	validators: { onChange: schema } (Yup still works; Zod recommended)
formik.handleSubmit	handleSubmit(onValid)
value + onChange + onBlur + name (4 props)	{...register("name")} (one spread)
formik.values.x	watch("x") or formState-driven components
formik.errors.x / formik.touched.x	formState.errors.x / formState.touched.x
<Field> / <FieldArray> render-prop components	register + useFieldArray hook, or AutoForm

El Form has no render-prop <Field>/<FieldArray> components — the hooks-first API replaces them, and AutoForm can generate an entire form from a schema if you want zero boilerplate.

After migrating

• Forms are accessible by default — see the Accessibility notes (no work needed on your end).
• Consider AutoForm for simple/CRUD forms — it generates the whole form from your schema.
• See the useForm API reference for the complete surface.

Hitting a migration snag that isn't covered here? Open an issue — the docs grow from real migration questions.