Gist on how i setup teamcity, based on octopus deploy's script.

something.ps1

# These are project build parameters in TeamCity
# Depending on the branch, we will use different major/minor versions
$majorMinorVersionMaster = "%system.MajorMinorVersion.Master%"
#$majorMinorVersionMaster = "1.9.0"

# TeamCity's auto-incrementing build counter; ensures each build is unique
$buildCounter = "%build.counter%" 
#$buildCounter = "999" 

# This gets the name of the current Git branch. 
$branch = "%teamcity.build.branch%"
#$branch = "refs/heads/release-2.4.88"

# Sometimes the branch will be a full path, e.g., 'refs/heads/master'. 
# If so we'll base our logic just on the last part.
if ($branch.Contains("/")) 
{
  $branch = $branch.substring($branch.lastIndexOf("/")).trim("/")
}

Write-Host "Branch: $branch"

if ($branch -eq "master") 
{
 $buildNumber = "${majorMinorVersionMaster}.${buildCounter}"
 $buildInfo = "${majorMinorVersionMaster}.${buildCounter}"
 $buildSeries = $majorMinorVersionMaster.Substring(0, $majorMinorVersionMaster.IndexOf('.')) + '.0.0.0'
}
elseif ($branch -match "(\d+\.)(\d+\.)(\d+)$")
{
 $buildNumber = "${branch}.${buildCounter}"
 $buildInfo = "${branch}.${buildCounter}"
 $buildSeries = $branch.Substring(0, $branch.IndexOf('.')) + '.0.0.0'
}
elseif ($branch -match "release-.*") 
{
 $specificRelease = ($branch -replace 'release-(.*)','$1')
 $buildNumber = "${specificRelease}.${buildCounter}"
 $buildInfo = "${specificRelease}.${buildCounter}"
 $buildSeries = $specificRelease.Substring(0, $specificRelease.IndexOf('.')) + '.0.0.0'
}
else
{
 # If the branch starts with "feature-", just use the feature name
 $branch = $branch.replace("feature-", "")
 $buildNumber = "${majorMinorVersionMaster}.${buildCounter}"
 $buildInfo = "${majorMinorVersionMaster}.${buildCounter}-${branch}"
 $buildSeries = $majorMinorVersionMaster.Substring(0, $majorMinorVersionMaster.IndexOf('.')) + '.0.0.0'
}

Write-Host "##teamcity[buildNumber '$buildNumber']"
Write-Host "##teamcity[setParameter name='system.Version' value='$buildNumber']"
Write-Host "##teamcity[setParameter name='system.BuildInfo' value='$buildInfo']"
Write-Host "##teamcity[setParameter name='system.BuildSeries' value='$buildSeries']"