Julep dev mode works but strict deploy fails

TL;DR

Strict is the default and is what production runs. If you need source span pointers for debugging raw combinator DSL nodes, set JULEPSOURCECAPTURE=1. Dev mode (deploy(..., mode=dev)) keeps compiling and running locally but retains the diagnostics strict prod would block on, so works in dev never means it deploys.

The error

Julep dev mode works but strict deploy fails

Fix

1. Strict is the default and is what production runs. Expected: You get the expected result; the problem is gone.

2. If you need source span pointers for debugging raw combinator DSL nodes, set JULEPSOURCECAPTURE=1. Expected: You get the expected result; the problem is gone.

3. Re-run the original operation and confirm the error is gone. Expected: no error, normal output.

When to use

• You hit this exact error.
• The symptom matches: Julep dev mode works but strict deploy fails.

When NOT to use

• A different error message; the cause here is specific to this error.
• Unrelated issues with a different cause.
• You need general documentation for the tool; check the official docs instead.

Compatibility

Reported per the linked source.

Variant phrasings

Julep dev mode works but strict deploy fails

Why it happens

My Julep flow works in dev mode but will not deploy to production. What is the difference between dev and strict mode?

Edge cases

• If your error message differs even slightly, this is probably a different issue; search the exact text.
• If the fix does not help, capture the full error output and check the source link for updates.

Source: My Julep flow works in dev mode but will not deploy to production. What is the difference between dev and strict mode?

Verified resolution: Strict is the default and is what production runs. Dev mode (deploy(..., mode=dev)) keeps compiling and running locally but retains the diagnostics strict prod would block on, so works in dev never means it deploys. Before shipping, call deployment.prodgapsummary() to see exactly what strict prod would reject, and clear that gap. Two more things that bite people: Temporal stays prod-strict, so Deployment.run(...) rejects dev-mode deployments outright, and Agent.deploy(...) uses the strict path. If you need source span pointers for debugging raw combinator DSL nodes, set JULEPSOURCECAPTURE=1.

Source URL: https://github.com/julep-ai/julep/blob/HEAD/docs-site/content/docs/guides/gotchas.md#dev-mode-vs-strict