Error Handling - Bun

Error Handling - BunDocumentation Index

Fetch the complete documentation index at: /docs/llms.txt

Use this file to discover all available pages before exploring further.

Skip to main contentBun home pageSearch...⌘KInstall BunSearch...NavigationHTTP serverError HandlingRuntimePackage ManagerBundlerTest RunnerGuidesReferenceBlogFeedback:first-child]:!hidden peer-[.is-custom]:[&>:first-child]:sm:!hidden peer-[.is-custom]:[&>:first-child]:md:!hidden peer-[.is-custom]:[&>:first-child]:lg:!hidden peer-[.is-custom]:[&>:first-child]:xl:!hidden">Get StartedWelcome to BunInstallationQuickstartTypeScriptTypeScript 6 and 7bun initbun createCore RuntimeBun RuntimeWatch ModeDebuggingREPLbunfig.tomlFile & Module SystemFile TypesModule ResolutionJSXAuto-installPluginsFile System RouterHTTP serverServerRoutingCookiesTLSError HandlingMetricsNetworkingFetchWebSocketsTCPUDPDNSData & StorageCookiesFile I/OStreamsBinary DataArchiveSQLSQLiteS3RedisConcurrencyWorkersProcess & SystemEnvironment VariablesShellSpawnWebViewCronInterop & ToolingNode-APIFFIC CompilerTranspilerUtilitiesCSRF ProtectionSecretsConsoleTOMLYAMLMarkdownJSON5JSONLHTMLRewriterImageHashingGlobSemverColorUtilsStandards & CompatibilityGlobalsBun APIsWeb APIsNode.js CompatibilityContributingRoadmapBenchmarkingContributingBuilding WindowsBindgenLicenseOn this pageerror callbackHTTP serverError HandlingCopy pagespan]:line-clamp-1 overflow-hidden group flex items-center py-0.5 gap-1 text-sm text-gray-950/50 dark:text-white/50 group-hover:text-gray-950/70 dark:group-hover:text-white/70 rounded-none rounded-r-xl border px-3 border-gray-200 aspect-square dark:border-white/[0.07] bg-background-light dark:bg-background-dark hover:bg-gray-600/5 dark:hover:bg-gray-200/5" aria-label="More actions" type="button" id="radix-_R_n4ctdbsnlht5lebsnpfdb_" aria-haspopup="menu" aria-expanded="false" data-state="closed">*]:[overflow-wrap:anywhere]">

Learn how to handle errors in Bun’s development server

Copy pagespan]:line-clamp-1 overflow-hidden group flex items-center py-0.5 gap-1 text-sm text-gray-950/50 dark:text-white/50 group-hover:text-gray-950/70 dark:group-hover:text-white/70 rounded-none rounded-r-xl border px-3 border-gray-200 aspect-square dark:border-white/[0.07] bg-background-light dark:bg-background-dark hover:bg-gray-600/5 dark:hover:bg-gray-200/5" aria-label="More actions" type="button" id="radix-_R_1cctdbsnlht5lebsnpfdb_" aria-haspopup="menu" aria-expanded="false" data-state="closed">To activate development mode, set development: true. server.ts

Bun.serve({
development: true,
fetch(req) {
throw new Error("woops!");
},
});

In development mode, Bun will surface errors in-browser with a built-in error page. ​error callback To handle server-side errors, implement an error handler. This function should return a Response to serve to the client when an error occurs. This response will supersede Bun’s default error page in development mode.

Bun.serve({
fetch(req) {
throw new Error("woops!");
},
error(error) {
return new Response(`
${error}\n${error.stack}
`, {
headers: {
"Content-Type": "text/html",
},
});
},
});

Learn more about debugging in Bun

Was this page helpful?

YesNoSuggest editsRaise issueTLSPreviousMetricsNext⌘IxgithubdiscordyoutubePowered byThis documentation is built and hosted on Mintlify, a developer documentation platform