The Engineering Productivity team at Pinterest is responsible for supporting the engineers who build and deploy software

Cloning monorepos that have a lot of code and history is time consuming, and we need to do it frequently throughout the day in our continuous integration pipelines. For Pinboard alone, we do more than 60K git pulls on business days. Most of our Jenkins pipeline configuration scripts (written in Groovy) start with a “Checkout” stage where we clone the repository that the later stages will build and test. Here’s what a typical “Checkout” stage looks like:

By simply adding the refspec option and specifying which refs we care about (master, in our case), we can limit the refs to the branch we care about and save a lot of time. Here’s what that looks like in our pipeline code:

All our larger efforts are designed to progress on the goal of making software development and delivery at Pinterest a fast and painless experience. Recently, we were reminded of how small details can also have a large impact on that goal. We discovered an overlooked Git option that significantly reduced the build times in our continuous integration pipelines. In order to understand how this small change had such a large impact, we need to share a little information on our monorepos and our pipelines.

It dawned on me today that this must be what it is like to be a man. People assume I know what I am talking about. Some people look for opportunities to smooth the way for me in routine interactions. My errand time is cut by at least 25%. I save time and energy because…people believe I am worth it.

More than being great, other people agree that I am great. Chapel Hill is a small town. It is also a company town. I forget that. Everyone from my real estate agent to my ophthalmologist has emailed me congratulations. Thanks to the grapevine and Vivian, word is out.

Even though we’re telling Git to do a shallow clone, to not fetch any tags, and to fetch the last 50 commits, we’re still not running this operation as fast as we could be. That’s because we aren’t setting the refspec option. Notice that by not setting it in the pipeline configuration script, we’re telling Git to fetch all refspecs: refs/heads/*:refs/remotes/origin/*. In the case of Pinboard, that operation would be fetching more than 2,500 branches.

To learn more about Engineering at Pinterest, check out our Engineering Blog, and visit our Pinterest Labs site. To view and apply to open opportunities, visit our Careers page.

We have six main repositories at Pinterest: Pinboard, Optimus, Cosmos, Magnus, iOS, and Android. Each one is a monorepo and houses a large collection of language-specific services. Pinboard is as old as the company and is the largest monorepo. Pinboard has more than 350K commits and is 20GB in size when cloned fully.

To learn more about Engineering at Pinterest, check out our Engineering Blog, and visit our Pinterest Labs site. To view and apply to open opportunities, visit our Careers page.

This simple one line change reduced our clone times by 99% and significantly reduced our build times as a result. Cloning our largest repo, Pinboard went from 40 minutes to 30 seconds. It goes to show that sometimes our small efforts can have a big impact as well.

Word is so out that when I go to the eye doctor or call to order books or buy a ticket for a drive-in movie, sometimes people make the connection. A strange thing happens next. People assume that my time is valuable. Just today someone offered to just “email [my] test results” because they know that I am so busy.

http://svt.munich.es/fmi/v-ideos-kahramanmarasspor-v-amed-v-tr-tr-1jit-4.php

http://svt.munich.es/fmi/Video-kahramanmarasspor-v-amed-v-tr-tr-1cqu-25.php

http://svt.munich.es/fmi/v-ideos-kahramanmarasspor-v-amed-v-tr-tr-1efn-4.php

http://svt.munich.es/fmi/videos-kahramanmarasspor-v-amed-v-tr-tr-1umt-28.php

http://old.cocir.org/media/fxa/video-kahramanmarasspor-v-amed-v-tr-tr-1rno-10.php

http://old.cocir.org/media/fxa/Video-kahramanmarasspor-v-amed-v-tr-tr-1qfs-5.php

http://old.cocir.org/media/fxa/Video-kahramanmarasspor-v-amed-v-tr-tr-1emf-20.php

http://old.cocir.org/media/fxa/video-kahramanmarasspor-v-amed-v-tr-tr-1kza-22.php

http://stream88.colomboserboli.com/eca/videos-sakaryaspor-v-kastamonuspor-v-tr-tr-1bbq-3.php

http://stream88.colomboserboli.com/eca/videos-sakaryaspor-v-kastamonuspor-v-tr-tr-1rye-21.php

http://stream88.colomboserboli.com/eca/v-ideos-sakaryaspor-v-kastamonuspor-v-tr-tr-1bux-26.php

http://agro.ruicasa.com/vtm/video-sivas-belediyespor-v-elaziğspor-v-tr-tr-1dqx-3.php

http://stream88.colomboserboli.com/eca/video-sakaryaspor-v-kastamonuspor-v-tr-tr-1ecs-29.php

http://agro.ruicasa.com/vtm/v-ideos-sivas-belediyespor-v-elaziğspor-v-tr-tr-1mjf-6.php

http://agro.ruicasa.com/vtm/v-ideos-sivas-belediyespor-v-elaziğspor-v-tr-tr-1bhh-20.php

http://agro.ruicasa.com/vtm/Video-sivas-belediyespor-v-elaziğspor-v-tr-tr-1uix-3.php

http://old.cocir.org/media/fxa/v-ideos-batman-petrolspor-v-osmaniyespor-v-tr-tr-1sgd-3.php

http://old.cocir.org/media/fxa/Video-batman-petrolspor-v-osmaniyespor-v-tr-tr-1wmh-7.php

http://old.cocir.org/media/fxa/videos-batman-petrolspor-v-osmaniyespor-v-tr-tr-1qka-24.php

http://old.cocir.org/media/fxa/videos-batman-petrolspor-v-osmaniyespor-v-tr-tr-1gfj-14.php

, but this simple strategy played a starring role in helping me lose 60 pounds in 60 days when I moved to Spain a decade ago. It’s also my go-to exercise for article ideas. The fresh air clears my head just enough to give my foggy thoughts some clarity.

There is nothing bad about being a MacArthur Fellow itself. People keep asking me how I am doing or how my day is going. I laugh. Are you kidding me? My day is going great. I stubbed my toe, burned my toast, and mailed the tax bill to the cable company. I lost my keys. I got soap in my eyes. I am a MacArthur Fellow. I AM GREAT.

Like most developer productivity teams, we work on large services that have a big impact on our day-to-day experience. However, it’s sometimes the one line fixes that can make a huge difference. Our work is about understanding that.

That, in turn, brought to mind Saidiya V. Hartman (another MacArthur Fellow) who pokes at how racism makes time work differently to sustain itself by making sure Black people die sooner and non-Black people die later.