Consider a module Test.res with the following code:

let context = React.createContext(0) module ContextProvider = { let make = React.Context.provider(context) } @react.component let make = (~children) => { <ContextProvider value=42> {children} </ContextProvider> }

Without JSX preserve mode enabled, the compiler output is (correct):

function Test(props) { return JsxRuntime.jsx(make, { value: 42, children: props.children }); }

With JSX preserve mode:

function Test(props) { return <make value={42}> {props.children} </make>; }

However, make is not a valid React component name as it is not uppercase.