Errors

Common CLI and build error messages, their cause, and the fix.

Message	Cause and fix
`handler must default-export an object with fetch(request)`	The file has no `export default { fetch(...) }`.
`imports are not supported` / `Node, Bun, and Deno APIs are not supported`	Remove `import` / `require` / `process` / `node:*`. One file, standard JS only.
`outbound networking needs an \`outbound` host allowlist`	Add the host to `outbound` in `sproutboat.jsonc`.
`binding X: no resource <id>`	The config references an id you do not own. Run the storage product’s `create` command, such as `sproutboat kv create <name>`, or use a bare name and let deploy provision it — see Storage resources.
`not serving after 90s`	The sprout is crashing or Caddy is still issuing the cert. Check `sproutboat tail --sprout`.
`X does not resolve to this server` (on `domains verify`)	Add the A record, DNS-only. Re-run after DNS propagates — see Custom domains.
`deploy the project at least once before ...`	`secrets` and `domains` require an existing deployment.