Error map
DEP0005 DeprecationWarning: Buffer() is deprecated due to security and usability issues (DEP0005)
Node.js · layer 4, Application & API
Centre: this error. First ring: errors it is linked with (12). Outer ring: what those are linked with. Colours show the layer of a request each error belongs to. Click any dot to re-centre the map on it; hover to follow its connections. The centre dot opens the error page.
Directly related (12)
npm WARN EBADENGINE Unsupported engine / The engine "node" is incompatible with this module
A package requires a different Node.js version than the one you’re running.
Deprecated: Implicit conversion from float 2.5 to int loses precision
PHP 8.1+ warns when a float with a fractional part is silently converted to int (array keys, % operator, int parameters).
Warning: findDOMNode is deprecated and will be removed in the next major release.
A component (often an old library like react-transition-group v1, react-draggable) uses findDOMNode, which StrictMode flags and R…
Error: Unhandled 'error' event (events.js / node:events)
An EventEmitter (stream, socket, child process, server) emitted 'error' and nothing listened for it, so Node crashed.
WRONGTYPE Operation against a key holding the wrong kind of value
A Redis command was used on a key of a different type (e.g. HGET on a string key).
Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated
PHP 8.1+ warns when null is passed to a built-in function that expects a string/int.
Warning: componentWillMount has been renamed, and is not recommended for use.
A class component uses legacy lifecycle methods (componentWillMount/WillReceiveProps/WillUpdate).
Error [ERR_HTTP_HEADERS_SENT]: Cannot set headers after they are sent to the client
An Express/Node handler tried to send a second response (or set headers) after one was already sent.
Express: req.body is undefined / {} (body parser missing)
Express didn’t parse the request body because no body-parsing middleware matched the request’s Content-Type.
npm WARN deprecated package@1.2.3: This package is no longer supported.
A dependency (often a transitive one) is deprecated by its author.
npm WARN config global `--global`, `--local` are deprecated. Use `--location=global` instead.
A deprecation warning printed by npm 8.11–8.12 for the --global flag.
Deprecated: Creation of dynamic property Foo::$bar is deprecated
PHP 8.2+ deprecates creating properties that aren’t declared in the class.
Two steps away (30)
Error: Cannot find module 'x' (MODULE_NOT_FOUND)
Node can’t resolve the module path — the package isn’t installed, or a relative path/extension is wrong.
Gradle: Could not resolve all files for configuration / Could not resolve dependency
Gradle couldn’t download a dependency — wrong coordinates/version, missing repository, offline mode, or network/proxy issues.
Duplicate class X found in modules A and B
Two dependencies ship the same class — typically old Android Support libraries mixed with AndroidX, or Kotlin stdlib-jdk7/jdk8 ve…
java.lang.ClassCastException: class A cannot be cast to class B
An object was cast to a type it isn’t.
Fatal error: Uncaught TypeError: foo(): Argument #1 ($x) must be of type int, string given
A function received a value of the wrong type for a typed parameter.
Warning: Array to string conversion
An array was used where a string is expected — echoing it, concatenating it, or passing it to a string function.
Authentication plugin 'caching_sha2_password' cannot be loaded
An old MySQL client/driver can’t use MySQL 8’s default authentication plugin.
DeprecationWarning: The `punycode` module is deprecated (DEP0040)
A dependency imports Node’s built-in punycode module, deprecated since Node 21.
Warning: ReactDOM.render is no longer supported in React 18. Use createRoot instead.
The app uses the legacy root API, so React 18 features (concurrent rendering, automatic batching) are disabled.
Error: listen EADDRINUSE: address already in use :::3000
Another process is already listening on that port.
SyntaxError: Cannot use import statement outside a module
An `import` statement ran in a context treated as CommonJS (Node without "type": "module", a browser script without type="module"…
Error: listen EACCES: permission denied 0.0.0.0:80
Node isn’t allowed to bind that port — ports below 1024 need root on Linux/macOS, and some Windows ports are reserved.
ReplyError: NOAUTH Authentication required.
The Redis server requires a password (or ACL user) but the client didn’t authenticate.
WordPress: Error establishing a Redis connection (object cache)
The persistent object cache drop-in (object-cache.php) can’t connect to Redis, so the whole site fails.
Fatal error: Uncaught TypeError: Unsupported operand types: string + int
An arithmetic or array operator was used with incompatible types (PHP 8 is stricter than PHP 7).
WARN: the attribute `version` is obsolete, it will be ignored
A harmless Compose v2 warning: the top-level version: line in docker-compose.yml is no longer used.
WordPress on PHP 8: Fatal error: Uncaught Error: Call to undefined function create_function() / each()
An old plugin/theme uses functions removed in PHP 8 (create_function, each), so the site breaks after a PHP upgrade.
[vite] hmr invalidate … Could not Fast Refresh. Export is incompatible.
Fast Refresh fell back to a full reload because the file exports non-components alongside components.
Warning: Function components cannot be given refs. Attempts to access this ref will fail. Did you mean to use React.forwardRef()?
A ref was passed to a function component that doesn’t forward it.
Warning: Support for defaultProps will be removed from function components in a future major release.
A function component (often inside a library) uses Component.defaultProps.
Warning: Cannot modify header information - headers already sent
You called `header()`, `setcookie()` or `session_start()` after output had already been sent to the browser.
TypeError: Router.use() requires a middleware function but got a Object
app.use()/router.use() received an object instead of a function — usually a router module that wasn’t exported.
TypeError: Missing parameter name at 1 (path-to-regexp)
An Express 5 (path-to-regexp v8) route uses old wildcard syntax like '*' or '/:id?'.
ValidationError: User validation failed: email: Path `email` is required.
A document failed Mongoose schema validation before saving.
npm ERR! code ERESOLVE — unable to resolve dependency tree
npm 7+ found conflicting peer dependency requirements and refuses to install a broken tree.
npm ERR! code E404 — 404 Not Found: package@version is not in this registry
npm asked the registry for a package (or version) that doesn’t exist there — a typo, a private/scoped package without auth, or th…
npm ERR! code ETARGET — No matching version found for package@^9.9.9
The version range in package.json doesn’t match any published version of the package.
npm WARN old lockfile — The package-lock.json file was created with an old version of npm, so supplemental metadata must be fetched
The lockfile is lockfileVersion 1 (npm 6) and npm 7+ is upgrading it.
npm ERR! cb() never called!
An old npm crash during install — usually network/cache corruption.
Error: Cannot find matching keyid (Corepack signature verification)
An older Corepack couldn’t verify the signature of a newly published pnpm/yarn release after npm rotated its signing keys.
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