error-troubleshooting

This error means you forgot to call .build() before execution. The correct pattern is runtime.execute(workflow.build()), since WorkflowBuilder must be compiled into a Workflow before the runtime can execute it.

Nexus blocks when LocalRuntime is used in async containers or when auto_discovery conflicts with DataFlow. Use AsyncLocalRuntime and create Nexus with auto_discovery=False, then register workflows manually with app.register().

Connection exhaustion happens because each Gunicorn worker creates its own pool. Create one pool at app startup and pass it to AsyncSQLDatabaseNode via the external_pool parameter, sizing max_size as database max connections divided by worker count.

This usually means the add_connection parameters are in the wrong order. The correct 4-parameter order is from_node, from_output, to_node, to_input, and nested outputs require dot notation such as result.filters.

No, DataFlow nodes do not accept {{}} templates and will raise errors like invalid literal for int(). Use explicit workflow connections to pass values between nodes, which preserves Python type safety.

Cycles fail to converge when the convergence criteria uses nested paths or when no max_iterations limit is set. Use flattened field names in converge_when(), always set max_iterations, and provide initial parameters for the first iteration.