It is like this in build log,
7:34:06 PM: Starting build script
7:34:06 PM: Installing dependencies
7:34:06 PM: Python version set to 2.7
7:34:07 PM: Started restoring cached node version
7:34:09 PM: Finished restoring cached node version
7:34:10 PM: v12.18.0 is already installed.
7:34:10 PM: Now using node v12.18.0 (npm v6.14.4)
7:34:10 PM: Started restoring cached build plugins
7:34:10 PM: Finished restoring cached build plugins
7:34:11 PM: Attempting ruby version 2.7.1, read from environment
7:34:12 PM: Using ruby version 2.7.1
7:34:12 PM: Using PHP version 5.6
7:34:12 PM: Started restoring cached go cache
7:34:12 PM: Finished restoring cached go cache
7:34:12 PM: go version go1.14.4 linux/amd64
7:34:12 PM: go version go1.14.4 linux/amd64
7:34:12 PM: Installing missing commands
7:34:12 PM: Verify run directory
It takes 6 seconds to install all the dependencies, however I need only node.js, but no python, ruby, php and go. The installation of node.js takes only 3 seconds. So, it can be 3 seconds faster if there is no installation of python, ruby, php and go.
For this site, It takes only 4 seconds from Netlify Build to Netlify Build Complete, and 4 seconds to prepare the repo.
7:34:14 PM: ────────────────────────────────────────────────────────────────
7:34:14 PM: Netlify Build
7:34:14 PM: ────────────────────────────────────────────────────────────────
7:34:18 PM: (build.command completed in 3.9s)
7:34:18 PM:
7:34:18 PM: ────────────────────────────────────────────────────────────────
7:34:18 PM: Netlify Build Complete
7:34:18 PM: ────────────────────────────────────────────────────────────────
7:34:18 PM:
7:34:18 PM: (Netlify Build completed in 3.9s)
7:34:02 PM: Starting to prepare the repo for build
7:34:02 PM: Netlify Large Media is enabled, running git commands with GIT_LFS_SKIP_SMUDGE=1
7:34:05 PM: Preparing Git Reference refs/heads/master
7:34:06 PM: Different publish path detected, going to use the one specified in the Netlify configuration file: 'public' versus 'public/' in the Netlify UI
7:34:06 PM: Starting build script
However the whole build process takes about 20 seconds, which means it kind of wastes nearly half of build time for things I don’t need. We both, netlify and I, esp. netlify since I am currently on starter, have to pay for it.
What I am suggesting is, users should be above the trim the build process, either by some ENVs or commands, or custom build images (for me I would like to test for node:alpine and hayd/deno:alpine).