Troubleshooting

Each section quotes an error as Elide prints it, then the fix.

No such built-in module

Error: No such built-in module: node:http2

node:http2, node:cluster, node:inspector and node:wasi are not available; require gives the code ERR_UNKNOWN_BUILTIN_MODULE. Without the node: prefix the message is Cannot find module 'http2'. A package that imports one at load time, such as Fastify, fails the same way. Check a module’s status in the API Overview.

Module not found after elide install

TypeError: Module not found: 'hono'

Plain elide install installs Maven dependencies only. With only a package.json, it prints nothing and exits 0. Install npm packages with:

elide install --ecosystems=npm

Python is not installed

Python support is not installed. Run 'elide setup python' to add it.

Exit code 2. Run elide setup python; elide info lists the installed languages on its Languages: line. A JavaScript file that imports a .py module before Python is installed exits 1 with Cannot import 'mod.py': Python support is not installed. and the same hint. With Python installed, calls between languages also need --interop; see Languages and Interop.

elide javac without --

error: '[-- TOOL_ARGS]…' can only be given after '--'

Usage: elide javac [FLAGS] [-- TOOL_ARGS]…

Arguments for javac, java, kotlinc and the other JDK tools go after --:

elide javac -- -d out Hello.java
elide java -- -cp out Hello

Kotlin classes fail under elide java

elide kotlinc -- -d kout Main.kt
elide java -- -cp kout MainKt

Exception in thread "main" java.lang.NoClassDefFoundError: kotlin/collections/CollectionsKt
	at MainKt.main(Main.kt:2)
	at MainKt.main(Main.kt)
Caused by: java.lang.ClassNotFoundException: kotlin.collections.CollectionsKt

elide java does not add the Kotlin standard library. Run the file with elide run Main.kt, or package the app as a Jvm.JvmApplication. kotlinc -include-runtime fails.

Sandbox denials

See Sandbox and Limits.

--deny-net without =

error: equal sign is needed when assigning values to '--deny-net=<HOSTS>'

Exit code 2. Write --deny-net=example.com; the same holds for --deny-run. The --allow-* flags take an optional value, so --allow-net example.com run app.js grants every host and tries to run a file named example.com:

No file or script named 'example.com'

Exit code 124

Error: --timeout 2s exceeded

--timeout=DURATION stopped the run. Raise it or remove it.

Exit code 3 and out of memory

--heap-dump-on-oom=FILE writes a heap dump when the heap is full, then exits 3:

Dumping heap to …/oom.hprof ...
Heap dump file created [308989015 bytes in 0.988 secs]

Without it, a full heap exits 1 with Could not allocate an unaligned heap chunk because the heap address space is exhausted. Raise --max-mem. A value of 128m or less fails before the program starts:

Failed to create isolate: INSUFFICIENT_ADDRESS_SPACE (802)

Port already in use

node:http reports a taken port:

Error: listen EADDRINUSE 127.0.0.1:3000

Fetch-handler servers (export default { fetch }, Elide.serve) report nothing: a second server on the same port starts, and requests alternate between the two processes. Stop the old one first:

ss -ltnp | grep :3000

A request returns 500 with no error printed

HTTP/1.1 500 Internal Server Error

A fetch handler that throws answers 500 Internal Server Error without printing the error. Wrap the handler in try/catch and log it. See Build an HTTP Service.

Express express.json() stops the server

TypeError: Buffer.isBuffer is not a function

express.json() and express.text() stop the process on the first request with a body. Read the body yourself or use express.raw(); see Frameworks.