Why can't I do composer install via teamcity ci? What can I do to make composer work?

Question

teamcity

I write build step:
php /usr/local/bin/composer install
as a result:

[14:58:50]Checking for changes
[14:58:53]Publishing internal artifacts
[14:58:53]Clearing temporary directory: /var/TeamCity/buildAgent/temp/buildTmp
[14:58:53]Checkout directory: /var/TeamCity/buildAgent/work/3f26b2643896c6f1
[14:58:53]Updating sources: server side checkout
[14:58:54]Step 1/2: List Files (Command Line)
[14:58:54]Step 2/2: Composer (Command Line)
[14:58:54][Step 2/2] Starting: /var/TeamCity/buildAgent/temp/agentTmp/custom_script2221618430436183158
[14:58:54][Step 2/2] in directory: /var/TeamCity/buildAgent/work/3f26b2643896c6f1
[14:58:54][Step 2/2] 
[14:58:54][Step 2/2] 
[14:58:54][Step 2/2]                                                                                             
[14:58:54][Step 2/2]   [RuntimeException]                                                                        
[14:58:54][Step 2/2]   The HOME or COMPOSER_HOME environment variable must be set for composer to run correctly  
[14:58:54][Step 2/2]                                                                                             
[14:58:54][Step 2/2] 
[14:58:54][Step 2/2] 
[14:58:54][Step 2/2] install [--prefer-source] [--prefer-dist] [--dry-run] [--dev] [--no-dev] [--no-plugins] [--no-custom-installers] [--no-scripts] [--no-progress] [-v|vv|vvv|--verbose] [-o|--optimize-autoloader] [packages1] ... [packagesN]
[14:58:54][Step 2/2] 
[14:58:54][Step 2/2] 
[14:58:54][Step 2/2] Process exited with code 1
[14:58:54][Step 2/2] Step Composer (Command Line) failed
[14:58:54]Publishing internal artifacts
[14:58:55]Build finished

What can I do to make composer work?

Answer 1

The HOME or COMPOSER_HOME environment variable must be set for composer to run correctly

here on this one. composer puts the cache in the user's home directory and takes data from these things for this.