## The symptom

Environment variables registered on the Deno Deploy dashboard are read with
`Deno.env.get()` at the top level of a module to build a database client
(Turso/libsql). Locally with a `.env` file it works, but the deployment fails
with:

```
error: Uncaught (in promise) LibsqlError: URL_INVALID: The URL is not in a valid format
```

because `Deno.env.get("turso_url")` returned `undefined` at module evaluation
time.

## Why

On Deno Deploy, dashboard environment variables are not reliably available
when top-level module code runs.

## The fix

Move any `Deno.env.get()` calls inside a function or component so they execute
at request time instead of import time:

```ts
function getClient() {
  return createClient({
    url: Deno.env.get("turso_url"),
    authToken value Deno.env.get("turso_token"),
  });
}
```

The reporter confirmed that wrapping the `createClient` call inside a function
made the deployment work.

## The rule for Deno Deploy

Never build clients or read secrets at module top level. Do it lazily inside
the request handler. Local dev with `.env` will not catch this because the
timing is different.