In my case I wanted to use the lambda image in gitlab-ci. The solution was to override the base image entrypoint by adding the following line to my Dockerfile:

ENTRYPOINT ["/bin/bash", "-l", "-c"]

Note that this means the image will not be usable in Amazon's lambdas anymore.

An alternative fix that does not require modifying the image is to override ENTRYPOINT in .gitlab-ci:

image:
    name: your_image_name
    entrypoint: ["/bin/bash", "-l", "-c"]

Another alternative to avoid messing with the entry point if you only need to run some commands manually could be the docker debug command.

Answer from Gabriel Devillers on Stack Overflow
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Reddit
reddit.com › r/aws › new to lambda: entrypoint requires the handler name to be the first argument
r/aws on Reddit: New to Lambda: entrypoint requires the handler name to be the first argument
May 14, 2023 -

I'm trying to get my first real Lambda function working and I'm hitting this error when I try to run it.

entrypoint requires the handler name to be the first argument

I'm pretty new to Lambda so I'll be a bit verbose about what I'm doing and why, and I'd appreciate it if people could tell me if I'm on the right lines with my general approach too.

It's a fairly involved Python image transformation tool that needs a lot of Linux utilities, so I'm deploying it as a container image. I started out building on a bog standard AL2 image, but it looks like implementing my own runtime would have been a lot of work, and the default Python images are more extensible than I thought.

So my Dockerfile looks like this:

FROM public.ecr.aws/lambda/python:3.8

RUN yum -y update && yum install -y \
	python3-pip \

...


RUN pip3 install -r requirements.txt --target "${LAMBDA_TASK_ROOT}"
RUN pip3 install -r lrd-requirements.txt --target "${LAMBDA_TASK_ROOT}"

COPY app.py "${LAMBDA_TASK_ROOT}"

CMD [ "app.lambda_handler" ]

And my app.py is like this (ignore the indentation in the handler, Reddit wasn't playing ball):

# import the necessary packages
import os
import sys
import requests

...

def lambda_handler(event, context):

print("Main triggered \n")
image_name,receipt_handle = image_download(download_path)
input_file_path = prep_files(download_path)                                                                        
process_image(input_file_path,image_name,render_factor,upload_bucket,output_path,receipt_handle)
image_upload(results_img_directory,image_name,upload_bucket,receipt_handle)
delete_sqs_message(queue,receipt_handle)
    
print("End of main")

So as far as I can tell I'm doing everything right according to all advice I've read, so can anyone see what's going wrong here please?

Discussions

Laravel Queue Dockerfile: entrypoint requires the handler name to be the first argument
I created a dockerfile for my queue service because its in an unsupported region, and couldn't use the native runtimes. Here is my Dockerfile FROM bref/php-83:2 COPY --from=bref/extra-pgsql-php-83:... More on github.com
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0
December 12, 2024
entrypoint requires the handler name to be the first argument
Hi everyone, I'm trying to build the local environment for develop Lambda functions with PHP. I modify the Dockerfile (https://github.com/aws-samples/php-examples-for-aws-lambda/blob/master/0.7-PHP... More on github.com
🌐 github.com
2
March 25, 2021
aws batch failure: "entrypoint requires the handler name to be the first argument"
I'm getting starting trying to make jobs run via AWS batch. My first submitted job failed with "entrypoint requires the handler name to be the first argument" logged to cloudwatch. Where should I... More on repost.aws
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0
July 9, 2024
docker - Using argument in CMD for a Dockerfile(entrypoint requires the handler name to be the first argument) - Stack Overflow
So, the question is how do I pass in LAMBDA_HANDLER argument AND have it be the first argument? Use entrypoint or custom shell script? Open to ideas about the approach ... If you're allowed to have a script as the handler, then you might create a short script with a fixed name that runs the ... More on stackoverflow.com
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GitHub
github.com › aws › aws-lambda-base-images › issues › 9
Docker Build with Environment Variables: entrypoint requires the handler name to be the first argument · Issue #9 · aws/aws-lambda-base-images
February 8, 2021 - As soon as I locally try a docker run -p 9000:8080 hello-lambda --env AWS_ACCESS_KEY_ID --env AWS_REGION --env AWS_SECRET_ACCESS_KEY, I get the following message: "entrypoint requires the handler name to be the first argument."
Author   hannahscovill
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GitHub
github.com › brefphp › bref › issues › 1896
Laravel Queue Dockerfile: entrypoint requires the handler name to be the first argument · Issue #1896 · brefphp/bref
December 12, 2024 - I created a dockerfile for my queue service because its in an unsupported region, and couldn't use the native runtimes. ... FROM bref/php-83:2 COPY --from=bref/extra-pgsql-php-83:1 /opt /opt # Copy the source code in the image COPY . /var/task RUN echo "extension=pdo_pgsql.so" >> /opt/bref/etc/php/conf.d/bref.ini # Configure the handler file (the entrypoint that receives all HTTP requests) CMD ["Bref\\LaravelBridge\\Queue\\QueueHandler"]
Author   michaelaguiar
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GitHub
github.com › aws-samples › php-examples-for-aws-lambda › issues › 23
entrypoint requires the handler name to be the first argument · Issue #23 · aws-samples/php-examples-for-aws-lambda
March 25, 2021 - functions: task_get_data: timeout: 60 handler: tasks/get_data.php layers: - ${bref:layer.php-73} task_post_data: timeout: 60 handler: tasks/post_data.php layers: - ${bref:layer.php-73}
Author   tho-actrecipe
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GitHub
github.com › aws › aws-lambda-dotnet › issues › 1324
AWS lambda in docker container run local · Issue #1324 · aws/aws-lambda-dotnet
September 26, 2022 - I get the error message: entrypoint requires the handler name to be the first argument.
Author   schmallaria
Find elsewhere
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Chariot Solutions
chariotsolutions.com › home › getting started with lambda container images
Getting Started with Lambda Container Images — Chariot Solutions
February 16, 2022 - However, there is a difference: if you specify ENTRYPOINT, then that program is run on startup and CMD (if present) provides it with command-line arguments. In the case of Lambda Container Images, ENTRYPOINT is defined by the base container and specifies the “bootstrap” program, /lambda-entrypoint.sh; CMD must be defined by your Dockerfile, and specifies the fully-qualified name of your handler function.
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GitHub
github.com › leocavalcante › aws-lambda-swoole-runtime › blob › main › docker-entrypoint.sh
aws-lambda-swoole-runtime/docker-entrypoint.sh at main · leocavalcante/aws-lambda-swoole-runtime
October 4, 2022 - echo "entrypoint requires the handler name to be the first argument" 1>&2 · exit 142 · fi · export _HANDLER="$1" ·
Author   leocavalcante
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npm
npmjs.com › package › @bitblit › epsilon
@bitblit/epsilon - npm
September 5, 2024 - # Modifications copyright Christopher Weiss, 2022 if [ -z "${EPSILON_RUNNING_IN_AWS_BATCH}" ]; then if [ $# -lt 1 ]; then echo "entrypoint requires the handler name to be the first argument" 1>&2 exit 142 fi export _HANDLER="$1" RUNTIME_ENTRYPOINT=/var/runtime/bootstrap if [ -z "${AWS_LAMBDA_RUNTIME_API}" ]; then exec /usr/local/bin/aws-lambda-rie $RUNTIME_ENTRYPOINT else exec $RUNTIME_ENTRYPOINT fi else echo "Running Epsilon inside AWS batch - triggering direct $1 $2" exec node dist/aws-batch-epsilon-cli.ts --process $1 --data $2 fi ·
      » npm install @bitblit/epsilon
    
Published   Sep 05, 2024
Version   4.1.100
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Medium
medium.com › @chienhaotan › custom-binaries-on-aws-lambda-poking-around-bonus-2aad6e4da3a5
Custom Binaries on AWS Lambda + Poking Around (Bonus) | by Chien Hao Tan | Medium
December 27, 2023 - All Rights Reserved. if [ $# -ne 1 ]; then echo "entrypoint requires the handler name to be the first argument" 1>&2 exit 142 fi export _HANDLER="$1" RUNTIME_ENTRYPOINT=/var/runtime/bootstrap if [ -z "${AWS_LAMBDA_RUNTIME_API}" ]; then exec /usr/local/bin/aws-lambda-rie $RUNTIME_ENTRYPOINT else exec $RUNTIME_ENTRYPOINT fi
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Pedal
pedal.com.tw › post › entrypoint-requires-the-handler-name-to-be-the-first
entrypoint requires the handler name to be the first argument
December 12, 2024 - The error "Entrypoint requires the handler name to be the first argument" indicates that your application's startup configuration isn't correctly specifying the function that should be executed when the application starts.
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YouTube
youtube.com › watch
Resolving the Entrypoint Requires the Handler Name Error in AWS Lambda Container Images - YouTube
Learn how to define the correct handler name to avoid entrypoint errors in AWS Lambda container images. This guide covers specifics for different runtimes li...
Published   August 11, 2025
Views   6
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Casip
casip.ca › educationai › entrypoint-requires-the-handler-name-to-be-the-first
entrypoint requires the handler name to be the first argument
December 18, 2024 - This error, "EntryPoint requires ... or Google Cloud Functions. It signifies a mismatch between how your function's entry point is defined and how the runtime environment expects it to be invoked....
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Colorado News
tickets.coloradorapids.com › home › tutorials › entrypoint requires the handler name to be the first argument
Entrypoint Requires The Handler Name To Be The First Argument - Colorado News
April 14, 2025 - Here’s how you could implement ... console.log("Stopping the application..."), // Add more handlers as needed }; const handlerName = process.argv[2]; if (handlers[handlerName]) { handlers[handlerName](); } else { ...
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Reddit
reddit.com › r/aws › python lambda image
r/aws on Reddit: python lambda image
February 10, 2023 -

I'm trying to deploy a lambda passing the function as a build ARG, but getting the following error "entrypoint requires the handler name to be the first argument" If I hardcode the handler into the Dockerfile CMD this builds and functions. What am I missing?

``FROM public.ecr.aws/lambda/python:3.8

ARG FUNCTION

ENV HANDLER=$FUNCTION

...Stuff...

CMD "${HANDLER}``