Evyatar Alush

Form Validation. The Tested Way

What if your form validation logic was as clear and testable as your unit tests? Discover a declarative, framework-agnostic library that makes it possible.

Form Validation. The Tested Way
#1about 5 minutes

Why user experience with forms is often broken

A personal story about a frustrating tax form highlights common UX failures like unclear requirements and delayed feedback.

#2about 6 minutes

Analyzing common form validation patterns and their pitfalls

Existing validation solutions often lack structure, are hard to test, and create tight coupling with UI frameworks.

#3about 2 minutes

Adopting a unit testing syntax for declarative validations

Vest is inspired by unit testing libraries like Mocha and Jest to create declarative, readable, and separate validation suites.

#4about 5 minutes

Live coding: Setting up a basic validation suite in React

Learn how to create a validation suite with Vest, connect it to a React form, and display error messages for individual fields.

#5about 5 minutes

Refining validation UX with field isolation and warnings

Use Vest's `only` function to validate a single field on interaction and implement non-blocking warnings for optional suggestions.

#6about 7 minutes

Implementing complex asynchronous and memoized validations

Manage asynchronous server-side checks, skip them conditionally with `skipWhen`, and prevent redundant calls using memoization.

#7about 2 minutes

A summary of Vest's features and future roadmap

Vest is a tiny, stateful library that offers declarative, framework-agnostic validations, with a full TypeScript rewrite in version 4.

#8about 5 minutes

Q&A: Handling dynamic forms and global validation rules

Learn how to handle debounced async calls, define global rules by extending `enforce`, and manage dynamic forms with `test.each` or manual cleanup.

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Matching moments

Automating formal processes risks losing informal human value
03:48 MIN

Automating formal processes risks losing informal human value

What 2025 Taught Us: A Year-End Special with Hung Lee

Why HR struggles with technology implementation and adoption
04:22 MIN

Why HR struggles with technology implementation and adoption

What 2025 Taught Us: A Year-End Special with Hung Lee

Balancing the trade-off between efficiency and resilience
03:38 MIN

Balancing the trade-off between efficiency and resilience

What 2025 Taught Us: A Year-End Special with Hung Lee

Developing resilience by expanding your capacity for failure
04:57 MIN

Developing resilience by expanding your capacity for failure

What 2025 Taught Us: A Year-End Special with Hung Lee

Rapid-fire thoughts on the future of work
02:44 MIN

Rapid-fire thoughts on the future of work

What 2025 Taught Us: A Year-End Special with Hung Lee

Breaking down silos between HR, tech, and business
03:39 MIN

Breaking down silos between HR, tech, and business

What 2025 Taught Us: A Year-End Special with Hung Lee

The industry's focus on frameworks over web fundamentals
11:32 MIN

The industry's focus on frameworks over web fundamentals

WeAreDevelopers LIVE – Frontend Inspirations, Web Standards and more

The importance of a fighting spirit to avoid complacency
06:04 MIN

The importance of a fighting spirit to avoid complacency

The Future of HR Lies in AND – Not in OR

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