Ask any frontend web developer: forms can be notoriously difficult. You have to keep up with filled and unfilled fields, which of them are valid, display errors when your users invariably attempt to enter invalid data, and depending on state, allow the form to be submitted or prevent submission entirely.

Working on the backend couldn’t be more different. I trained initially on data validation in server-side languages before considering JavaScript, HTML, and CSS as potential disciplines. In my world, form validation and error reporting was largely a solved problem: applications evaluate the complete dataset by a clearly defined validation rules. The result, valid or invalid, is returned to the user. From the application’s point of view, transient states are rare.

Entry, as pointed out by the frontend engineer, should be effortless for the user. Relating errors to a given field is critical for the success of this happy path. On the other hand, our server is largely concerned with how deeply values are nested, and the total size of our serialized object.

Both scenarios are made easier by well-formed APIs.

The Ultimate Form System

Here at Uptime Ventures, we’re always interested in tools that ease common developer processes. All applications, regardless of platform, need to receive user input, which is generally a form. In early 2018, I wondered if we could invent a cross platform library that tidied user experience flows and enhance developer happiness when dealing with complex inputs.

We’ve done it, and the result is even better than I could’ve hoped for. Allow me to introduce the Ultimate Form System (UFS); a concise form validation library, designed to meet our demanding needs, and now available to you. UFS presents a unified API that feels natural across iOS, Android, and the web, starting with tools provided by React and React Native. Here’s a brief example:

import React from 'react'
import Form from '@uptimeventures/ufs-react'
import { Input, Textarea } from '@uptimeventures/ufs-dom'

const Contact = () => (
    validate={values => ({})},
    handleSubmit={values => {}}
    {({ handleSubmit }) => (
        placeholder="Your Name"
        placeholder="Your Message"

Behind the scenes, we’re using React’s Context API to drive data propagation. If the form has errors, parent components will render them only when the field values are invalid, and remove them when the errors are no longer present. And that’s UFS’ greatest strength: the library is only a few lines of non-magical JavaScript. Technically speaking, JSX and [React][react] are optional; though its declarative syntax is ideal for expressing our intent, we aren’t married to a specific framework.

Additionally, it’s possible that the API can become even cleaner as we explore upcoming language features.

Customizing UFS

While the above example is contrived, it demonstrates just how quickly you can develop a working form with UFS. However, because all of our pre-built elements (like <Input/> and <Textarea/>), are structured as higher-order components UFS’ real power is hidden below the surface.

I’ll use a specialized component, that you will likely employ, to explain.

import React from 'react'
import { withAPI } from '@uptimeventures/ufs-react'

const ErrorWrapper = withAPI(({ name, api: { errors }}) => (
    {errors[name] ? errors[name] : null}

While our component can store and use local state, state isn’t required. If the field we’re watching experiences an error, our component will be re-rendered with the error value, as shown above. Notice that we do this all without complex logic or markup.

You may have also noticed how logic and presentation concerns are split between the ufs and ufs-dom packages in our first example. This separation allows UFS to render anywhere React renders: on web or native platforms. It also eases graduation from using predefined components to developing your own, as shown above.

Upcoming Releases

UFS has been in use on internal projects for several months, and version 1.0.0 is just around the corner. DOM rendering should be considered stable, but I’d like to complete a basic component library for React Native prior to release. UFS will render on React Native, and we’re even using it in a few native applications, but have yet to release a prebuilt components library mirroring ufs-dom.

That’s where you come in. How can UFS improve further? It is already the only zero-dependency, most ergonomic, form design toolkit that we know of. But I’m certain we can take it further, together. Give it a try and let us know what you think.