3. Creating and Upgrading a Target System

3 Creating and Upgrading a Target System

When creating a system using Erlang/OTP, the simplest way is to install Erlang/OTP somewhere, install the application-specific code somewhere else, and then start the Erlang runtime system, making sure the code path includes the application-specific code.

It is often not desirable to use an Erlang/OTP system as is. A developer can create new Erlang/OTP-compliant applications for a particular purpose, and several original Erlang/OTP applications can be irrelevant for the purpose in question. Thus, there is a need to be able to create a new system based on a given Erlang/OTP system, where dispensable applications are removed and new applications are included. Documentation and source code is irrelevant and is therefore not included in the new system.

This chapter is about creating such a system, which is called a target system.

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