Skip to content
Switch branches/tags

Keith's Layers (Klayers)

🐍 A collection of Python Packages as AWS Lambda(λ) Layers 🐍

Python 3.8 Language grade: Python Code style: black

Layer List

List of all layer version arns are available by region here

There might be multiple versions for a single package, as we publish a new layer version if the package dependencies (requirements.txt) has been updated. Refer to Layer expiry for more data.

Note: We have deprecated layers for python3.6 and python 3.7, please use these newer versions that are built for python 3.8 going forward.

Python Packages

Just some examples of the ~70 packages we build every week, for a full list click here:

  • aws-lambda-powertools
  • aws-xray-sdk
  • bcrypt
  • beautifulsoup4
  • boto3
  • dynamodb-encryption-sdk
  • idna
  • lambda-cache
  • nltk
  • numpy
  • opencv-python-headless
  • openpyxl
  • pandas
  • parliament
  • Pillow
  • pulp
  • pycryptodome
  • PyJWT
  • pyqldb
  • pytesseract
  • pytz
  • PyYAML
  • requests
  • slackclient
  • spacy
  • ...

Status of layers

Click here to see specific dependencies of all the latest builds. Layers are built with the latest package version at 2am UTC every Sunday.

Using the Layers

You can use the layers anyway you see fit, here are 3 proposed options:

Option 1: Set ARN as layer

Click links below for your preferred version of python, and then select your region of choice, you will see a full list of layer version ARNs to use.

Once selected, you can add the arn directly from the console, by selecting Layers->Add a Layer->Specify an Arn:


Option 2: Download copy of layer

Use the Get Layer Version by ARN in python or aws-cli command which will provide an S3 location to download the layer as a zip.

Note: You can only get layers from the specific region your client is configured for, otherwise you'll get a AccessDeniedException error.

Option 3: Using Serverless Framework

You can include layers in your deployments, by utilizing the layers property at the function level, and setting it to the arn of your choice. You must use layers from the same region as your function:

  handler: 02_pipeline/check.main
  description: Checks for package on PyPi via the API
  runtime: python3.8
  timeout: 30
  memorySize: 256
  - arn:aws:lambda:${self:provider.region}:113088814899:layer:Klayers-python37-packaging:1
  - arn:aws:lambda:${self:provider.region}:113088814899:layer:Klayers-python38-aws-lambda-powertools:23

Layer expiry

Some layer versions will have a expiry_date field. This is the date for when the layers will be deleted.

In general, layers are scheduled for deletion 60 days after a new layer version has been published for that package. If you use that latest version of a layer, you're guaranteed at least 60 days before the layer is deleted.

All functions deployed with a layer will still work indefinitely, but you won't be able to deploy new functions referencing a deleted layer version.


Special hand-crafted binaries for layers. These layers are not automatically built, and hence slower update cycles, and will only work with python3.7 functions as the underlying OS is Amazon Linux 1.

Package ARN Version
pip arn:aws:lambda:<region>:113088814899:layer:Klayers-python37-pip:2 19.2.1 1
en_core_web_sm arn:aws:lambda:<region>:770693421928:layer:Klayers-python38-spacy_model_en_small:1 2.2.5 2
es_core_news_sm arn:aws:lambda:<region>:770693421928:layer:Klayers-python38-spacy_model_es_small:1 2.3.1 2

1 Python3.8 layers already have new version of pip, use only if on Python3.7

2 Spacy en_core_web_sm model, for use with the spacy layer refer here for more info.

Architecture Diagram


API (beta)

We've recently added an API under beta. All API calls are http-based, and work only with https (TLS1.2 and above). The API is heavily cached, so there could be minor delays in updates.

Get latest ARN for specific package in region

Returns data on the latest layer for a specific {package} in a specific {region}{region}/{package}


Get all ARNs for specific package in region

Returns data on the all layers (latest and deprecated) for a specific {package} in a specific {region}{region}/{package}


Get list of all built packages

Returns list of all packages currently being built, including dependencies and build date.


Special Thanks

Asking for additional layers

If you would like a new package to be made a layer, raise a pull request modifying the pipeline/config/Klayers-prodp38 file.