Making Referential Stability a Type
What happens when we stop treating referential stability as a linting heuristic and start carrying it through React and Preact as a type-level proof.
Jovi De Croock's Blog
Posts about web development, engineering, and thoughts.
Latest posts
Async hydration in Preact
How Preact resumes hydration across Suspense boundaries, why useId made that hard, and how streaming changes the tradeoffs.
Fed up with Belgium
A country drowning in debt decides the problem is the people still willing to build in it. A personal account of paying gladly for almost a decade, and the moment that changed.
Two Places to Stop a Bad Release
How Drydock uses npm staged publishing and GitHub release gates to review the package artifact before it can ship.
Hardening publishing & consuming
A practical look at reducing blast radius in npm publishing workflows — environment-gated OIDC publishing, limiting manual access, and what consumers can do on their end.
Bridging the Server-Client Boundary with Signals
How mixed-signals turns server-side Preact Signals into real-time shared state across clients, and what that can look like in tech like Cloudflare Durable Objects
I have changed my mind about GraphQL
Boilerplate became cheap, but GraphQL still wins when a durable schema contract matters across teams and clients.
Letting LLMs Debug Signal Lifecycles
How we turned Vite into a local debugging API so an LLM can inspect signal updates, page events, and network context while driving the browser.
Thinking About Effect Subscriptions
Understanding how effect automatically tracks signal dependencies and the edge cases where you need to be intentional about subscriptions.
Why Computed Signals Matter
Understanding the critical difference between using signal values directly and wrapping them in computeds for optimal performance.
Debugging signals
Understanding how to debug signals-based state changes and visualize the dependency graph.
The Browser Has Everything You Need
Stop treating SPAs and SSR as opposing paradigms. The browser already loads resources in parallel but you have to use it.
State and rerenders
Exploring the paradigm shift from 'render where you create state' to 'render where you use state'.
GraphQL Myths
Common misconceptions about GraphQL and how persisted operations address them.
Beyond Hooks, why Signals and State Models
Exploring how Preact Signals promote better separation of concerns through dedicated state models.
The GraphQL Asterisk Problem: When Benefits Come with Caveats
An exploration of the trade-offs and considerations when using GraphQL and its alternatives.
Tracking context
Signals and the way they register on tracking contexts within your application.
Child diffing, with offsets
In Preact 10.16 we drastically changed how we diff children in Preact, let's take a look at how it works.
Signals, pull-based values
Let's look at how signals can offer wins over hooks.
Fragments in VDOM
Fragments, a seemingly convenient subject isn't all that straight-forward.
Surgical Rendering with any API
A deep dive into how signals can optimize rendering performance across various API types.
GraphQL's missing feature
The concept of fragment composition is great but there's a fundamentally missing feature to make it feel great
Unreliable vendors
What can we do to prevent our applications getting taken down by third parties, and if we do go down, how can we optimise for recovery.
GraphQL Caching Abstract Types
A quick exploration of how a client-side cache looks at abstract and concrete types in GraphQL.
GraphQL Development Workflow
An opinionated development workflow I have enjoyed using when it comes to GraphQL.
GraphQL Persisted Operations
Persisted operations are a way to introduce caching and additional security to your GraphQL Endpoint.
Unique identifier in Preact
Getting unique tree-identifiers consistent across server and client.
Browser timings
When exploring a bug in Preact we came across a few quirks with regards to (micro)ticks and events.
Controlled inputs
Controlled and uncontrolled inputs have always been a big subject, what does it actually mean, to be (un)controlled?
Hydration in Preact
We see a lot of talk about hydration, what is it and where is it applied?
State and VDOM
We often talk about state in context, ... but this can be a footgun, let's take a closer look at how library authors bypass this.
Suspense, data and SSR
How do we handle Asynchronous data in a situation where it feels the runtime is idle, how does Suspense tie into this and extending into ssr.
Virtual Dom optimizations
As one of the core maintainers of Preact I think a lot about VDOM and how to optimize the common actions of library-consumers.