Nicolas Charpentier's Blog

Access Your Homelab Services Without Memorizing IPs and Ports

Thu, 19 Feb 2026 12:00:00 GMT

How I made my homelab services easily accessible with a Heimdall dashboard, local domain names via mDNS, and default ports.

Bun Code Coverage Gap

Tue, 09 Dec 2025 00:00:00 GMT

Bun's test runner only tracks coverage for loaded files. Here's how to expose the gaps.

Configure "Go to Definition" to Open TypeScript Source

Wed, 19 Nov 2025 00:00:00 GMT

Learn how to fix "Go to Definition" navigating to type declarations instead of source files in TypeScript projects.

Don't Blindly Use useTransition Everywhere

Thu, 06 Nov 2025 00:00:00 GMT

Let's take a closer look at useTransition and why the React Docs example might not be a great starting point for real-world UX.

How to Easily Reproduce a Flaky Test in Playwright

Fri, 28 Mar 2025 00:00:00 GMT

Stop playing whack-a-mole with flaky Playwright tests by using CPU throttling to reliably reproduce CI failures on your local machine.

Minimizing Risk: Properly and Safely Resolving CVEs in Your Dependencies

Fri, 04 Oct 2024 00:00:00 GMT

How to properly and safely update dependencies to resolve CVEs, while also gathering an understanding of how package managers handle dependencies.

TypeScript Tips: Safely Using includes With ReadonlyArrays

Tue, 28 May 2024 00:00:00 GMT

How to use includes on ReadonlyArrays while retaining type safety and narrowing down the type.

Speeding up ESLint—Even on CI

Thu, 25 Apr 2024 00:00:00 GMT

Gotta Cache 'Em All: Leverage ESLint's cache to speed it up.

Apollo Client's Hidden Gems: Interface-Based Type Policies

Mon, 22 Jan 2024 00:00:00 GMT

Did you know that type policies can also be applied to interfaces and not just to "types"!? 🤯

UI Flickering With Apollo Client: Previous Data to the Rescue!

Tue, 10 Oct 2023 00:00:00 GMT

Have you ever noticed that using Apollo Client could lead to some UI flickers within your app? Especially when you refetch. Let's see how using previousData could help solve this bad UX.

GraphQL Enums Are Unsafe

Tue, 26 Sep 2023 12:00:00 GMT

We often talk about how we shouldn't introduce breaking changes in GraphQL, but fail to mention how enums in GraphQL are, by nature, almost always introducing breaking changes. Let's go over best practices to write resilient GraphQL applications.

Open-Ended Unions and Autocomplete With TypeScript

Tue, 26 Sep 2023 00:00:00 GMT

Let's see how to achieve an open-ended union in TypeScript to provide autocomplete on literal string unions.

Graphite: The End of Mammoth Pull Requests? My Experience

Mon, 25 Sep 2023 00:00:00 GMT

Ever felt trapped by colossal pull requests or tangled in merge conflicts? Dive into my experience with Graphite, the game-changer in code reviews. Discover the power of stacking, stay unblocked, and embrace a smoother Git journey. 🚀

Testing TypeScript Types: Part 2 (Advanced Solutions)

Wed, 09 Aug 2023 00:00:00 GMT

Advanced solutions to test TypeScript types.

Testing TypeScript Types: Part 1

Tue, 08 Aug 2023 00:00:00 GMT

Preamble and early solution to start testing TypeScript types.

Properly type Object.keys and Object.entries

Mon, 07 Aug 2023 00:00:00 GMT

Have you ever noticed that Object.keys and Object.entries are a little bit tricky to work with in TypeScript? They won't return what you would expect. Here's how to properly type them.

Use Custom Merge Driver to Simplify Git Conflicts

Thu, 03 Aug 2023 00:00:00 GMT

Tired of solving merge conflicts manually when it could be automated? Let's leverage Git's custom merge driver to simplify the process.

Enforce Best Practices Incrementally With Betterer

Wed, 02 Aug 2023 00:00:00 GMT

Using Betterer to adopt, enforce, and teach best practices incrementally without having to refactor the whole codebase.

Agile Rotisserie

Tue, 20 Dec 2022 00:00:00 GMT

Software Engineering is like cooking chicken.

Be Careful With JavaScript Default Parameters!

Thu, 03 Nov 2022 00:00:00 GMT

In JavaScript and TypeScript, we often rely on default parameters to define optional parameters, but should we?

Find What Commit Introduced a Bug With Git Bisect

Tue, 01 Nov 2022 00:00:00 GMT

Let's see how to efficiently track down a bug even without knowing the codebase.

Array.prototype.groupBy to the rescue!

Wed, 15 Dec 2021 00:00:00 GMT

Ever wondered how to do array grouping properly with JavaScript? Good news, Array.prototype.groupBy is coming soon.

Wrapping Gatsby's with TypeScript

Tue, 30 Nov 2021 00:00:00 GMT

How to properly wrap Gatsby's component while preserving GatsbyLinkProps type.

Setting up an Example App for Your React Native Library

Mon, 01 Apr 2019 00:00:00 GMT

Having a hard time with a React Native example app? Here’s how you can simplify this with Metro bundler.

React Native at Classcraft

Mon, 23 Jul 2018 00:00:00 GMT

We had to carefully find a way to introduce React Native bit-by-bit into the existing native application.

Arrow Functions in Class Properties Might Not Be As Great As We Think

Thu, 16 Nov 2017 00:00:00 GMT

Since the last year, the Class Properties Proposal simplify our life, especially in React with the internal state, or even with statics ones like propTypes and defaultProps. But, should we really use arrow functions in class field properties?

5 Things You Should Know About ES8

Fri, 14 Jul 2017 00:00:00 GMT

ECMAScript 2017 8th edition (ES2017/ES8) has been officially released and published a few weeks ago, let’s figure it out some important changes. All of these are available with Node 8 and with the latest version of browsers without babel or any polyfills.

Continuous Integration with Angular CLI

Thu, 13 Jul 2017 00:00:00 GMT

Angular CLI is a powerful tool to scaffold and build Angular apps. Not only it provides you scalable project structure, instead, it handles all common tedious tasks for you out of the box and it already follows the Angular best practices.

Reliable Continuous Integration in JavaScript

Wed, 18 Jan 2017 00:00:00 GMT

When you build a piece of software you want to build a reliable one, so often you’re using various continuous integration tools. But, is your continuous integration process is as reliable as you think?