Better Stack AWS Lambda logging

Which language is your AWS Lambda using?

• Node.js
• Python

Logging in AWS Lambda running Node.js

Collect logs from your AWS Lambda running Node.js code.

1. Install

Download the logtail/logtail-lambda-extension Lambda layer and publish it in your AWS account:

curl -fsSLO https://github.com/logtail/logtail-lambda-extension/releases/latest/download/logtail-lambda-extension.zip
aws lambda publish-layer-version \
    --layer-name "logtail-lambda-extension" \
    --zip-file "fileb://logtail-lambda-extension.zip" \
    --compatible-runtimes nodejs22.x nodejs24.x \
    --compatible-architectures x86_64 arm64

Take care to publish the layer in the region your Lambda function resides in. If that's not your default region, you can change it by adding --region <region-name> parameter to the command above.

2. Add layer to your Lambda functions

In your AWS Console, add the logtail-lambda-extension layer to the Node.js Lambda functions you want to collect logs from.

This can be done in Lambda → Functions → your function → Layers section. For details, check AWS docs.

3. Configure your source token

In your AWS Console, set up SOURCE_TOKEN and INGESTING_HOST environment variables for the AWS Lambda functions like this:

SOURCE_TOKEN:   $SOURCE_TOKEN
INGESTING_HOST: $INGESTING_HOST

This can be done in Lambda → Functions → your function → Configuration → Environment variables. For details, check AWS docs.

4. Start logging

Use the logger as usual:

console.error('Something bad happened.')
console.info('Log message with structured logging.', {
    'item': "Orange Soda",
    'price': 100.00
})

You should see your logs in Better Stack → Logs & traces.

Logging in AWS Lambda running Python

Collect logs from your AWS Lambda running Python code.

1. Install

Install Logtail Python and AWS Lambda Powertools PyPI packages:

pip3 install logtail-python
pip3 install aws-lambda-powertools

2. Setup

Set up AWS Lambda logger with Better Stack:

from logtail import LogtailHandler
from aws_lambda_powertools import Logger

logtail_handler = LogtailHandler(
    source_token='$SOURCE_TOKEN',
    host='https://$INGESTING_HOST',
    flush_timeout=1,
)
logger = Logger(service="example-service", logger_handler=logtail_handler, level="INFO")

3. Start logging

Use the logger as usual, and call logtail_handler.flush() in a finally block so the logs are sent before AWS Lambda freezes the function:

def lambda_handler(event, context):
    try:
        logger.error('Something bad happened.')
        logger.info('Log message with structured logging.', extra={
            'item': "Orange Soda",
            'price': 100.00
        })
    finally:
        logtail_handler.flush()

You should see your logs in Better Stack → Live tail.

Need help?

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Additional information

Interested in learning more about enriching log context and using formatters? Head over to official AWS Lambda Powertools docs.