How to install a dependency library to an Arduino compilation environment?

Question

Following approach A from this Arduino SE answer, I managed to kick off an Arduino CLI compilation in a Docker environment.

However, the project I am trying to compile has a dependency on a LCD control library.

Error output:

...../OpenSourceVentilator/OpenSourceVentilator.ino:494:116: 
fatal error: LiquidCrystal_PCF8574.h: 
No such file or directory
compilation terminated.

What is the proper way to link dependencies to the compilation environment of an Arduino project?

While the source suggests a direct compiler call, maybe I need a Makefile instead of the following?

arduino-cli compile --fqbn esp32:esp32:esp32 -o ignored.bin OpenSourceVentilator.ino

• chrisl: The tutorial, that you linked to as approach A from the other question, also has a part, which explains how to install extra libraries
• J. Doe: @chrisl is that also an "Arduino-like" way or is there a more standard approach/package manager?
• chrisl: Why do you expect a non-Arduino like or more standard approach, when using the Arduino CLI?
• J. Doe: I just wonder there is no management for external libraries Golang-style, but maybe it's even good.

Answer 1

If the library is installed the Arduino IDE (or CLI I assume too) just finds it and compiles/links it for you.

• J. Doe: so what activities does installation of a library include if the library is on GitHub?
• Majenko: arduino.cc/en/guide/libraries