01
JavaScript and Python
Pick the language your team knows. Python includes its standard library for parsing, dates and math.
Your logic, in the workflow.
JavaScript or Python.
When a built-in step is not quite right, write a few lines. Reshape data, apply your own rules and hand the result to the next step, without running a server.
See how it worksWRITE IT, RUN IT
Real code. Clear boundaries.
Code steps take the workflow's data in and return plain JSON, so every result is easy to inspect in the run.
02
Data in, data out
Your code receives the step's items, input and variables as JSON and returns JSON for the next step.
03
Isolated by design
Every run gets a fresh sandbox with no network, files or server access, separate from every other run and workspace.
04
Limits you can see
Two seconds by default, up to ten, and 64 MB of memory. A step that runs long stops with a clear message.
05
Logs in the run
Print while you build. Up to 100 log lines appear with the step's output in the run history.
06
Part of the whole workflow
Combine code with triggers, approvals, data tables and connections. Steps are never counted or billed.
THE PRACTICAL DETAILSBefore you
Before you
get started.
Which languages can a code step run?
JavaScript and Python. Each run uses a fresh sandboxed interpreter compiled to WebAssembly, with Python's standard library available read-only.
Can my code call the internet or read files?
No. Code steps have no network, file system or environment access. Use a connection step for an API call and pass its result into your code.
How long can a code step run?
Two seconds by default and up to ten seconds, with 64 MB of memory. A result can be up to 2 MB of JSON.
Do code steps cost extra?
No. A code step is one step of a workflow run, and NodeHub never counts or bills steps.