Adrian Hall

Product Architect by day; Open-source developer by night

1 minute read

I’m doing some Azure Functions development in JavaScript at the moment, using the new azure-functions-core-tools. One of the features it has is command line publication, like this:

$ func azure functionapp publish my-function-app

I have a single function right now (called ping). Running the publish step creates a ZIP file:

$ npx func azure functionapp publish my-function-app               
Getting site publishing info...
Creating archive for current directory...
Uploading 187.62 MB [##---------------------------------------------------------------------]

That’s a big file. Wow! It creates a ZIP file of the whole directory!!!! My function isn’t that big!

Looking at the directories, it’s obvious which ones are the culprit:

$ du -ks */.           
462952  node_modules/.
8       ping/.
4       tools/.
$ du -ks node_modules/*/.
du -ks node_modules/*/. | sort -rn
451588  node_modules/azure-functions-core-tools/.
3600    node_modules/es5-ext/.
3088    node_modules/es-abstract/.
624     node_modules/ext/.
424     node_modules/type/.
412     node_modules/deferred/.
360     node_modules/resolve/.
156     node_modules/npm-run-all/.
128     node_modules/object-inspect/.
104     node_modules/es6-iterator/.
100     node_modules/es6-symbol/.
96      node_modules/object.assign/.
92      node_modules/timers-ext/.
88      node_modules/event-emitter/.
88      node_modules/es-to-primitive/.
80      node_modules/semver/.
# ...

Getting rid of azure-functions-core-tools from the published source would reduce the file size considerably. Fortunately, the tooling provides .funcignore for precisely this problem. Just add node_modules/azure-functions-core-tools to your .funcignore file. Now, the publication looks like this:

$ npx func azure functionapp publish my-function-app
Getting site publishing info...
Creating archive for current directory...
Uploading 1.7 MB [##########################################################################]
Upload completed successfully.

It knocked about 4 minutes from my publication time, and reduced the file size down to under 2MB.

If you use TypeScript, you should also add the node_modules/typescript package to the .funcignore as that is pretty big too.

Of course, this doesn’t mean anything if the functions don’t work at the end of it. I’m happy to report that my ping API works just fine, so the azure-functions-core-tools isn’t required within the publish package. It’s also given me 5-10 minutes back per publication cycle.

Leave a comment

You may also enjoy

AI Assisted Editors: A Comparison (Part 2)

August 01, 2025  10 minute read  

In my last article, I provided a break down of the three commercial AI assisted editors that I use on a regular basis. However, not everyone can afford a monthly subscription ($20/month is the standard), or maybe you prefer different models or a more local development environment. There are still options that you can use to get AI assisted editing yet avoid the subscription charge. What is an AI Assisted Editor? As a developer, you open up an editor and write code. AI Assisted editors ...

AI Assisted Editors: A Comparison (Part 1)

August 01, 2025  13 minute read  

You can’t go a lap about development these days without bumping into AI assisted editors. Most of the AI tooling companies I see are heavily investing in Visual Studio Code based editors, but you have some others out there as well. I’m going to break the comparison I’m doing into three articles - one on the paid offerings I’ve personally used, one on the “free” offerings I’ve used, and one on the quirks of the LLMs that are in common use. Hopefully, by the end of this, you’ll understand th...

Customizing Keycloak with Aspire - Part 3

October 04, 2024  7 minute read  

This is the last article in a trio of articles about incorporating Keycloak into .NET Aspire applications. Thus far, I’ve covered the basics and some common customizations. This part covers what you need to do if you want to store the identity information within a PostgreSQL database. I’ve chosen PostgreSQL for this because it seems to be the database of choice for Aspire when you want to run things locally and in the cloud and also because the PostgreSQL database driver is included by def...

Customizing Keycloak with Aspire - Part 2

September 30, 2024  5 minute read  

In my last article, I introduced the Keycloak identity service and showed how the development version can be easily integrated into a project. Development services get you started quickly and allow you to defer the details until later on. At some point, however, you need to take control of your service and start working towards production. There are a number of things that the development version of the Keycloak identity service doesn’t do that you need in production. These include SSL/TL...