Frequently Asked Questions

What about hx?

hx was the library which helix originated from. hx was created with similar goals and ideas, but continued use and experimentation led to the desire to remove or change several portions of the library which would break the few people that had adopted it.

Rather than do a breaking change, a new name was created with the updated API. Notable changes was the removal of hx's hiccup interpreter, using kebab-case for all APIs, and a new focus on compile-time optimizations and linting.

What about hiccup?

Hiccup is great. Hiccup, however, comes at a cost; it is very difficult to statically convert hiccup to React Elements at compile time. At run time, creating vectors that are then parsed and turned into React Elements is a slight, but constant, performance tax on your application and makes me feel bad about warming the planet up just to save a few keystrokes.

Popular libraries like Reagent, which parse hiccup at runtime, ameliorates this performance cost by trying to give the developer tight control over when and where state updates trigger renders; a single state update, if it is depended on by 3 leaf nodes, will only trigger a render of those individual leafs. React state, passed down by a parent, will instead trigger a render of the parent and the entire tree will re-render. This means that using React's local component state and passing down props feels the performance problems posed by hiccup much greater.

However, Reagents methods of selectively rendering subscribed components comes with tradeoffs, especially when trying to use Concurrent Mode. Subscriptions to external state are a big part of the conversation when talking about migrating to Concurrent Mode.

"Tearing" is a common term used when a Concurrent Mode render cycle pauses, then resumes and ends up reading different values at different points in time from an external store. This can cause strange bugs that are hard to debug at development time. Selectively using external subscriptions can have huge performance gains, but have to be used with wisdom and judgement, and according to the React team should not be the default.

This long train of thought about state management, rendering methods, and performance is why the (pretty rough, not optimized) hiccup interperter was removed when moving from the hx name to helix. It didn't fit with the overall goal of giving users a performant, ergonomic default method for creating React applications.

If you want to use libraries like sablono, hicada or even hx hiccup parser, you can easily add that by creating a custom macro.