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Applies to:
  • Plan -
  • Deployment -

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Summary

Goal: Emit traces to two separate projects with distinct root spans simultaneously. Features: Multiple logger instances with independent project targets and setCurrent: false configuration.

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Configuration Steps

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Step 1: Create primary logger

Initialize the main logger for your primary project. 
// TypeScript
import { initLogger } from "braintrust";

const primaryLogger = initLogger({
  projectName: "my-primary-project",
  apiKey: process.env.BRAINTRUST_API_KEY,
});

# Python
from braintrust import init_logger

primary_logger = init_logger(
    project="my-primary-project",
    api_key=os.environ["BRAINTRUST_API_KEY"],
)

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Step 2: Create secondary logger with setCurrent: false

Initialize a second logger targeting the other project with setCurrent: false to prevent conflicts. 
// TypeScript
const secondaryLogger = initLogger({
  projectName: "shared-visibility-project",
  apiKey: process.env.BRAINTRUST_API_KEY,
  setCurrent: false, // Prevents this logger from becoming the global default
});

# Python
secondary_logger = init_logger(
    project="shared-visibility-project",
    api_key=os.environ["BRAINTRUST_API_KEY"],
    set_current=False,  # Prevents this logger from becoming the global default
)

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Step 3: Log to both projects

Use each logger instance to create distinct traces in their respective projects. 
// TypeScript
primaryLogger.log({ input: "request", output: "response" });
secondaryLogger.log({ input: "request", output: "response" });

# Python
primary_logger.log(input="request", output="response")
secondary_logger.log(input="request", output="response")

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Use Case Example

Emit traces to both a shared service project and the consuming application’s project for dual visibility without post-processing.