diff --git a/Octopus.Client/PowerShell/Feeds/PurgeNugetFeeds.ps1 b/Octopus.Client/PowerShell/Feeds/PurgeNugetFeeds.ps1
deleted file mode 100644
index 0502dc94..00000000
--- a/Octopus.Client/PowerShell/Feeds/PurgeNugetFeeds.ps1
+++ /dev/null
@@ -1,515 +0,0 @@
-<#
-
-.SYNOPSIS
-Applies Octopus release retention policies to associated packages on NuGet feeds.
-
-.DESCRIPTION
-Mimics how Octopus natively applies retention policies to its Built-in Package Repository, but applies them to
-external NuGet feeds. ref: https://octopus.com/docs/administration/retention-policies#built-in-repository
-
-Uses Octopus and NuGet APIs to identify and delete any package that meets all of these criteria:
-* the package is on an Octopus-configured External Feed that:
- * is of type Nuget Feed
- * has a feed username (API key) defined
- * meets the -ExcludeFeedRegex and -IncludeFeedRegex criteria
-* the package's name is associated with an Octopus release
-* the package's name/version combination is not associated with an Octopus release
-* the package's version is lower than the highest version of the package associated with an Octopus release
-
-.PARAMETER ExcludeFeedRegex
-Packages will not be purged from feeds having URLs that match this regular expression. Examples:
--ExcludeFeedRegex '$^' # Default. Purge packages from any feeds with URLs that match -IncludeFeedRegex.
--ExcludeFeedRegex '/foo-core/' # Do not purge packages from e.g. feed http://foonugetserver/foo-core/nuget
-
-.PARAMETER IncludeFeedRegex
-Packages will not be purged from feeds having URLs that do not match this regular expression. Examples:
--IncludeFeedRegex '.*' # Default. Purge packages from any feeds except those with URLs that match -ExcludeFeedRegex.
--IncludeFeedRegex 'foo-hi' # Purge packages from e.g. feed http://foonugetserver/foo-hi/nuget
-
-.PARAMETER OctopusUri
-Example:
--OctopusUri 'http://foooctoserver/api'
-
-.PARAMETER OctopusApiKey
-Duh.
-
-.PARAMETER NugetPath
-Full path to the nuget CLI executable.
-
-.PARAMETER NugetSource
-A semicolon-delimited list of NuGet package sources (as URLs) to use for acquiring this script's dependent
-assemblies. If omitted, the package sources will be determined as described at
-https://docs.microsoft.com/en-us/nuget/consume-packages/configuring-nuget-behavior
-Example:
--NugetSource '\\some\packagesource;https://some/otherpackagesource'
-
-.PARAMETER PathToStoreDataAcrossRuns
-Full path to a folder where files from the script run can be accessed by the subsequent script run. Example:
--PathToStoreDataAcrossRuns '\\foonas\fooshare\Octopus-PurgeNugetFeeds-Data'
-
-.PARAMETER SpaceId
-The space ID (not name). This only affects which NuGet feeds are queried for candidate packages to purge. Example:
--SpaceId 'Spaces-1' # Default
-
-.PARAMETER IgnoreRecentPackagesThresholdInSeconds
-Protects packages from purging based on their Published timestamp. This was added to help address cases where
-newer packages are being published with lower versions. Example:
--IgnoreRecentPackagesThresholdInSeconds 3600 # Default (1 hour)
-
-.PARAMETER ProceedEvenIfPreviousRunMayHavePurgedPackagesItShouldNotHave
-If this switch is present, the script will ignore the result of the following check: At the beginning of each
-run, the script saves a file under -PathToStoreDataAcrossRuns listing any packages that Octopus reports as
-missing from feeds that comply with -ExcludeFeedRegex and -IncludeFeedRegex. Just before saving that file, the
-script compares the current list with the one saved the previous time the script was run. If the current list
-includes any packages that the previous list does not, the cause could be that during the
-previous run the script did not work as intended and purged packages still associated with releases.
-To avoid the possibility of further data loss, the script throws an exception and stops without purging
-anything (unless this switch is present).
-
-.PARAMETER UseCachedListOfPackagesInUse
-Intended only to speed up debugging. Loads the list of packages associated with Octopus releases from a file
-saved during the previous run instead of calculating the list by querying Octopus. Example:
-
-.OUTPUTS
-
-None
-
-.EXAMPLE
-
-Syntax for Arguments parameter of TFS Powershell step:
--Confirm:$($false) -WhatIf:$$(foo.WhatIf) -Verbose:$$(system.debug) -IncludeFeedRegex '/foo-' -ExcludeFeedRegex '/foo-core/' -OctopusUri '$(foo.OctopusUri)' -OctopusApiKey '$(foo.OctopusApiKey)' -PathToStoreDataAcrossRuns $(foo.PathToStoreDataAcrossRuns)
-
-#>
-[CmdletBinding(SupportsShouldProcess)] # Enable -WhatIf and -Verbose switches
-Param(
-	[parameter()][string]$ExcludeFeedRegex = '$^',
-	[parameter()][string]$IncludeFeedRegex = '.*',
-	[parameter(Mandatory=$true)][string]$OctopusUri,
-	[parameter(Mandatory=$true)][string]$OctopusApiKey,
-	[parameter(Mandatory=$true)][string]$NugetPath,
-	[parameter()][string]$NugetSource,
-	[parameter(Mandatory=$true)][string]$PathToStoreDataAcrossRuns,
-	[parameter()][string]$SpaceId = 'Spaces-1',
-	[parameter()][int]$IgnoreRecentPackagesThresholdInSeconds = 3600, # (1 hour)
-	[parameter()][switch] $ProceedEvenIfPreviousRunMayHavePurgedPackagesItShouldNotHave,
-	[parameter()][switch] $UseCachedListOfPackagesInUse
-)
-$ErrorActionPreference = 'Stop'
-if ($PSBoundParameters['Debug']) {
-	$DebugPreference = 'Continue' # avoid Inquire
-}
-
-function AcquireAssemblies() {
-	[CmdletBinding()]
-	Param()
-	Write-Host 'Acquiring dependent assemblies'
-	if ($NugetSource) {
-		$nugetSourceArg = '-Source'
-	} else {
-		$nugetSourceArg = ''
-	}
-	@('Octopus.Client', 'Octostache') | % { 
-		& $NugetPath install $_ $nugetSourceArg $NugetSource -ExcludeVersion -PackageSaveMode nuspec -Framework net40 -Verbosity $script:NugetVerbosity -NonInteractive
-	}
-}
-
-function LoadAssemblies() {
-	[CmdletBinding()]
-	Param()
-	@('Markdig', 'Sprache') | % { 
-		Copy-Item ".\$_\lib\net40\$_.dll" '.\Octostache\lib\net40\' -Force -WhatIf:$false -Confirm:$false
-	}
-Write-Verbose 'Loading dependent assemblies'
-	@(
-		'.\Newtonsoft.Json\lib\net40\Newtonsoft.Json.dll', 
-		'.\Octopus.Client\lib\net452\Octopus.Client.dll'
-		'.\Octostache\lib\net40\Octostache.dll'
-	) | % { Add-Type -Path $_ }
-}
-
-function Get-InUsePackages {
-	[CmdletBinding()] # Enable -Verbose switch
-	[OutputType('System.Collections.Generic.Dictionary[string, Octopus.Client.Model.PackageResource]')]
-	Param ( 
-		[parameter(Mandatory=$true)][Octopus.Client.Model.ReleaseResource]$Release
-	)
-	$packageVersions = @{}
-	foreach ($selectedPackage in $Release.SelectedPackages) {
-		$packageVersions[$selectedPackage.ActionName] = $selectedPackage.Version
-	}
-	$headers = @{ "X-Octopus-ApiKey" = $OctopusApiKey }
-	$uri = [string]::Join('/', @(
-		$OctopusUri.TrimEnd('/'), 
-		$SpaceId,
-		'deploymentprocesses', 
-		$Release.ProjectDeploymentProcessSnapshotId))
-	$progPref = $ProgressPreference
-	$ProgressPreference = 'SilentlyContinue'
-	$deploymentProcessSnapshot = Invoke-WebRequest -Uri $uri -Headers $headers -Method Get -Verbose:$false | ConvertFrom-Json
-	$ProgressPreference = $progPref
-	$selectedPackageVersions = New-Object 'System.Collections.Generic.Dictionary[string,Octopus.Client.Model.PackageResource]'
-	foreach ($step in $deploymentProcessSnapshot.Steps) {
-		foreach ($action in $step.Actions) {
-			if ((!$action.IsDisabled) -and $packageVersions[$action.Name]) {
-				foreach ($package in $action.Packages) {
-					$selectedPackageVersion = New-Object 'Octopus.Client.Model.PackageResource'
-					$selectedPackageVersion.FeedId = $package.FeedId
-					$selectedPackageVersion.PackageId = Get-PackageId -Release $Release -PossibleOctostacheExpression $package.PackageId
-					$normalizedVersion = (New-Object 'Octopus.Client.Model.SemanticVersion' $packageVersions[$action.Name]).ToNormalizedString()
-					$selectedPackageVersion.Version = $normalizedVersion
-					$hash = [string]::Join(' ', @($selectedPackageVersion.FeedId, $selectedPackageVersion.PackageId, $selectedPackageVersion.Version))
-					$selectedPackageVersions[$hash] = $selectedPackageVersion
-				}
-			}
-		}
-	}
-	$selectedPackageVersions
-}
-
-function Test-FeedId {
-    [CmdletBinding()]
-	[OutputType('System.Boolean')]
-    Param(
-		[parameter(Mandatory=$true)][string]$FeedId
-	)
-	$result = $false
-	if ($script:IncludedFeedIds.Contains($FeedId)) {
-		$result = $true
-	} elseif (!$script:ExcludedFeedIds.Contains($FeedId)) {
-		if ($FeedId -like 'feeds-builtin*') {
-			Write-Verbose "Skipping feed '$FeedId'. This script only handles external feeds."
-		} elseif (!$script:AllFeeds.ContainsKey($FeedId)) {
-			Write-Verbose "Skipping feed '$FeedId'. Its details were not found even though it is associated with one or more packages from one or more releases."
-		} elseif (
-			($script:AllFeeds[$FeedId].FeedUri -match $ExcludeFeedRegex) -or `
-			($script:AllFeeds[$FeedId].FeedUri -notmatch $IncludeFeedRegex)
-			) {		
-			Write-Verbose "Skipping feed '$FeedId'. Its URL ($($script:AllFeeds[$FeedId].FeedUri)) does not comply with the ExcludeFeedRegex or IncludeFeedRegex parameters."
-		} elseif ($script:AllFeeds[$FeedId].SpaceId -ne $SpaceId) {
-			Write-Verbose "Skipping feed '$FeedId' ($($script:AllFeeds[$FeedId].FeedUri)) from space '($script:AllFeeds[$FeedId].SpaceId)'. Only feeds in space '$SpaceId' are being processed, based on the SpaceId parameter (or its default value)."
-		} elseif (!$script:AllFeeds[$FeedId].Username) {
-			Write-Warning "Skipping feed '$FeedId' ($($script:AllFeeds[$FeedId].FeedUri)). Its Username (API key) is not defined."
-		} else {
-			$result = $true
-		}
-		if ($result) {
-			$script:IncludedFeedIds += $FeedId
-		} else {
-			$script:ExcludedFeedIds += $FeedId
-		}
-	}
-	$result
-}
-
-function Test-PackagesWentMissingAfterPreviousRunStarted {
-	[CmdletBinding()]
-	[OutputType([void])]
-    Param(
-		[parameter(Mandatory=$true)][Octopus.Client.Model.PackageResource[]]$Packages,
-		[parameter(Mandatory=$true)][Octopus.Client.Model.NugetFeedResource[]]$Feeds
-	)		
-	Write-Host 'Querying Octopus for any packages that may be missing from applicable feeds.'
-	$packagesMissingNow = @{ 
-		IncludedFeedIds = $null;
-		PackagesMissing = Get-PackagesMissingFromFeeds -Packages $Packages -Feeds $Feeds
-	}
-	$packagesMissingNow.IncludedFeedIds = $script:IncludedFeedIds;
-	Write-Verbose "$($packagesMissingNow.PackagesMissing.Count) packages are missing; $($packagesMissingNow.IncludedFeedIds.Count) applicable feeds were checked."
-	$missingPackagesFile = [System.IO.Path]::Combine($PathToStoreDataAcrossRuns, "missing-packages-$($OctopusUri -replace '[^a-z0-9]', '-').xml")
-	if (Test-Path $missingPackagesFile -PathType Leaf) {
-		Write-Verbose "Loading list of packages Octopus reported missing from applicable feeds when the previous run started"
-		$packagesMissingWhenPreviousRunStarted = Import-Clixml $missingPackagesFile
-		Write-Verbose "$($packagesMissingWhenPreviousRunStarted.PackagesMissing.Count) packages were missing when the previous run started; $($packagesMissingWhenPreviousRunStarted.IncludedFeedIds.Count) applicable feeds were checked."
-	} else {
-		$packagesMissingWhenPreviousRunStarted = @{ IncludedFeedIds = @() ; PackagesMissing = New-Object 'System.Collections.Generic.List[Octopus.Client.Model.PackageResource]' }
-		Write-Verbose "Found no preexisting file at $missingPackagesFile"
-	}
-	$regrets = @()
-	foreach ($packageMissingNow in $packagesMissingNow.PackagesMissing) {
-		if ($packagesMissingWhenPreviousRunStarted.IncludedFeedIds.Contains($packageMissingNow.FeedId) `
-			-and @($packagesMissingWhenPreviousRunStarted.PackagesMissing | ? { 
-				($_.FeedId -eq $packageMissingNow.FeedId) `
-				-and ($_.PackageId -eq $packageMissingNow.PackageId) `
-				-and ($_.Version -eq $packageMissingNow.Version)
-			}).Count -eq 0) {			
-			$regrets += $packageMissingNow
-		}
-	}
-	if ($regrets.Count -gt 0) {
-		$message = "The following package(s) that should have been retained went missing during or after the previous run of this script: $([string]::Join('; ', ($regrets | % { $_.FeedId + ' ' + $_.PackageId + ' ' + $_.Version })))"
-		if ($ProceedEvenIfPreviousRunMayHavePurgedPackagesItShouldNotHave.IsPresent) {
-			Write-Warning $message
-		} else {
-			throw $message
-		}
-	}
-	# By design, this will not execute if the "throw" above executes.
-	Write-Verbose "Saving list of packages missing from applicable feeds"
-	$packagesMissingNow | Export-Clixml $missingPackagesFile -Force -WhatIf:$false -Confirm:$false
-}
-
-function Get-PackagesMissingFromFeeds {
-    [CmdletBinding()]
-	[OutputType('System.Collections.Generic.List[Octopus.Client.Model.PackageResource]')]
-    Param(
-		[parameter(Mandatory=$true)][Octopus.Client.Model.PackageResource[]]$Packages,
-		[parameter(Mandatory=$true)][Octopus.Client.Model.NugetFeedResource[]]$Feeds
-	)
-	# If in the future you are considering requesting multiple packages at once as an optimization, note that
-	# experimentation found that query strings a little longer than 14,000 characters could result in the
-	# following response: "Bad Request - Request Too Long / HTTP Error 400. The size of the request headers is
-	# too long."
-	$packagesOnAffectedFeeds = $Packages | ? { Test-FeedId $_.FeedId }
-	$packagesMissingFromFeeds = New-Object 'System.Collections.Generic.List[Octopus.Client.Model.PackageResource]'
-	$headers = @{ 
-		'X-Octopus-ApiKey' = $OctopusApiKey; 
-		'Cache-Control' = 'no-cache';
-		'Pragma' = 'no-cache'
-	 }
-	$packagesProgress = 0
-	$progPref = $ProgressPreference
-	$ProgressPreference = 'SilentlyContinue'
-	foreach ($package in $packagesOnAffectedFeeds) {
-		$packagesProgress++
-		Write-Verbose "Requesting notes for package $packagesProgress of $($packagesOnAffectedFeeds.Count)"
-		$uri = [string]::Join('/', @(
-			$OctopusUri.TrimEnd('/'),
-			$SpaceId,
-			'packages',
-			"notes?packageIds=$($package.FeedId)%3A$($package.PackageId)%3A$($package.Version)"))
-		$packageNotes = Invoke-WebRequest -Uri $uri -Headers $headers -Method Get -Verbose:$false | ConvertFrom-Json
-		if ($packageNotes.Packages[0].Notes.Succeeded -ne 'true') {
-			$packagesMissingFromFeeds.Add($package)
-		}
-	}
-	$ProgressPreference = $progPref
-	$packagesMissingFromFeeds
-}
-
-<#
-.SYNOPSIS
-Get-PackageId attempts to evaluate an Octostache expression from a release's deployment process snapshot using
-the same release's variable snapshots.
-
-Get-PackageId was implemented to address this scenario: Some process steps may define Octostache expressions 
-for the names of packages, for example to define different package names to use depending on a release's 
-channel. Unfortunately, deployment process snapshots contain only the octostache variable name, not the 
-evaluated package name (even though the dynamically-selected package version is recorded alongside it).
-
-Processing accounts for channels. Example:
-
-	VERBOSE: Requesting deployment process snapshot for release 571 of 1001
-	VERBOSE: '#{WebProjectPackageName}' evaluated to 'foo.App.Web'
-	VERBOSE: '#{DataProjectPackage}' evaluated to 'foo.App.Dacpac'
-
-	VERBOSE: Requesting deployment process snapshot for release 572 of 1001
-	VERBOSE: '#{WebProjectPackageName}' evaluated to 'foo.App.MVC'
-	VERBOSE: '#{DataProjectPackage}' evaluated to 'foo.App.DbSchema'
-#>
-function Get-PackageId {
-	[CmdletBinding()] # Enable -Verbose switch
-	[OutputType('System.String')]
-	Param (
-		[parameter(Mandatory=$true)][Octopus.Client.Model.ReleaseResource]$Release,
-		[parameter(Mandatory=$true)][string]$PossibleOctostacheExpression
-	)
-	if ([Octostache.VariableDictionary]::CanEvaluationBeSkippedForExpression($PossibleOctostacheExpression)) {
-		$PossibleOctostacheExpression
-	} else {
-		Write-Verbose "Attempting to evaluate possible Octostache expression '$PossibleOctostacheExpression'"
-		$headers = @{ "X-Octopus-ApiKey" = $OctopusApiKey }
-		$uri = [string]::Join('/', @(
-			$OctopusUri.TrimEnd('/'), 
-			$SpaceId,
-			'variables', 
-			$Release.ProjectVariableSetSnapshotId))
-		$progPref = $ProgressPreference
-		$ProgressPreference = 'SilentlyContinue'
-		$variableSetSnapshots = @(Invoke-WebRequest -Uri $uri -Headers $headers -Method Get -Verbose:$false | ConvertFrom-Json)
-		foreach ($libraryVariableSetSnapshotId in $Release.LibraryVariableSetSnapshotIds) {
-			$uri = [string]::Join('/', @(
-				$OctopusUri.TrimEnd('/'), 
-				$SpaceId,
-				'variables', 
-				$libraryVariableSetSnapshotId))
-				$variableSetSnapshots += Invoke-WebRequest -Uri $uri -Headers $headers -Method Get -Verbose:$false | ConvertFrom-Json
-			}
-		$ProgressPreference = $progPref
-		$snapshottedVariables = New-Object 'Octostache.VariableDictionary'
-		foreach ($variableSetSnapshot in $variableSetSnapshots) {
-			foreach ($variable in $variableSetSnapshot.Variables) {
-				if (
-					((!$Release.ChannelId) -or (!$variable.Scope) -or (!$variable.Scope.Channel)) `
-					-or `
-					$variable.Scope.Channel.Contains($Release.ChannelId)
-				) {
-					$snapshottedVariables[$variable.Name] = $variable.Value
-				}
-			}			
-		}
-		$evaluated = $snapshottedVariables.Evaluate($PossibleOctostacheExpression)
-		Write-Verbose "'$PossibleOctostacheExpression' evaluated to '$evaluated'"
-		$evaluated
-	}
-}
-
-function Remove-Package {
-    [CmdletBinding(SupportsShouldProcess, ConfirmImpact='High')] # Enable -WhatIf and -Verbose switches, require -Confirm:$false for non-interactive usage
-    Param(
-		[parameter(Mandatory=$true)][Octopus.Client.Model.NuGetFeedResource]$Feed,
-		[parameter(Mandatory=$true)][string]$PackageName,
-		[parameter(Mandatory=$true)][Octopus.Client.Model.SemanticVersion]$PackageVersion
-	)
-	$operation = "Deleting package '$PackageName.$($PackageVersion.ToNormalizedString())'"
-	if ($PSCmdlet.ShouldProcess($Feed.FeedUri, $operation)) {
-		Write-Host "$operation from feed '$($Feed.FeedUri)'"
-		& $NugetPath delete $PackageName $PackageVersion.ToNormalizedString() -Source $Feed.FeedUri -ApiKey $Feed.Username -Verbosity $script:NugetVerbosity -NonInteractive
-	}
-}
-
-function Get-PackageIdAndVersion {
-    [CmdletBinding()]
-	[OutputType('System.Collections.Generic.HashSet[string]')]
-    Param(
-		[parameter(Mandatory=$true)][Octopus.Client.Model.NuGetFeedResource]$Feed,
-		[parameter(Mandatory=$true)][System.DateTimeOffset]$PublishedNoLaterThan
-	)
-	# We consume the nuget API directly because of the following shortcomings of various API clients.
-	# - NuGet CLI (list command from nuget.exe or NuGet.Commands.ListCommandRunner from
-	#   nuget.client.dll): data corrpution possible due to wrapping of output if, for example,
-	#   WindowsSize.Width or BufferSize.Width is less than the combined length of the package ID and version.
-	#   refs:
-	#   https://github.com/NuGet/NuGet.Client/blob/3803820961f4d61c06d07b179dab1d0439ec0d91/src/NuGet.Clients/NuGet.CommandLine/Common/Console.cs#L264
-	#   https://github.com/NuGet/NuGet.Client/blob/dev/src/NuGet.Core/NuGet.Commands/ListCommand/ListCommandRunner.cs#L154
-	# - PackageManagement PowerShell module (Find-Package): not available on all environments; requires
-	#   PowerShell 5.0
-	# - Package Manager Console: Lacks a command to list packages without specifying a package ID
-	
-	$uri = [string]::Join('/', @(
-		$Feed.FeedUri.TrimEnd('/'), 
-		'Packages?$skip=0&$select=Id,NormalizedVersion,Published&$orderby=Id,NormalizedVersion&$filter=Listed%20eq%20true')
-	)
-		# ref: https://www.odata.org/documentation/odata-version-2-0/uri-conventions/
-	$packages = New-Object 'System.Collections.Generic.HashSet[string]'
-	$resultPage = 1
-	do {
-		$progPref = $ProgressPreference
-		$ProgressPreference = 'SilentlyContinue'
-		$response = Invoke-WebRequest -Uri $uri -Method Get -Verbose:$false
-		$ProgressPreference = $progPref
-		Write-Progress -Activity "Parsing page $($resultPage++;$resultPage) of packages on $($Feed.FeedUri)"
-		foreach ($packageProperties in ([xml]($response.Content)).feed.entry.properties) {
-			$published = [System.DateTimeOffset]::Parse($packageProperties.Published.InnerText)
-			if ($published -le $PublishedNoLaterThan) {
-			$packages.Add([string]::Join('.', @($packageProperties.Id, $packageProperties.NormalizedVersion))) | Out-Null
-			} else {
-				Write-Verbose "Ignoring package $($packageProperties.Id) $($packageProperties.NormalizedVersion) because it was published at $($published.ToLocalTime()), after the limit of $PublishedNoLaterThan."
-			}
-		}
-		$uri = ([xml]($response.Content)).feed.link | ? { $_.rel -eq 'next' } | % { $_.href }
-	} while ($uri)
-	$packages
-}
-
-function PurgeNugetFeeds() {
-	[CmdletBinding()]
-	Param()
-	$octopusRepository = (new-object Octopus.Client.OctopusRepository (new-object Octopus.Client.OctopusServerEndpoint $OctopusURI, $OctopusApiKey))
-	Write-Host 'Querying Octopus for releases'
-	$publishedNoLaterThan = [System.DateTimeOffset]::Now.Subtract([System.TimeSpan]::FromSeconds($IgnoreRecentPackagesThresholdInSeconds))
-	$releases = $octopusRepository.Releases.FindAll()
-	$inUsePackagesDescription = 'list of packages associated with Octopus releases'
-	$inUsePackagesCacheFile = [System.IO.Path]::Combine($PathToStoreDataAcrossRuns, "Cached $inUsePackagesDescription.xml")
-    if ($UseCachedListOfPackagesInUse.IsPresent) {
-		Write-Warning "Using cached $inUsePackagesDescription"
-		$inUsePackages = Import-Clixml $inUsePackagesCacheFile
-	} else {
-		Write-Host "Compiling $inUsePackagesDescription"
-		$inUsePackages = New-Object 'System.Collections.Generic.Dictionary[string,Octopus.Client.Model.PackageResource]'
-		$releasesCount = $releases.Count
-		$releasesProgress = 0
-		foreach ($release in $releases) {
-			$releasesProgress++
-			Write-Progress -Activity "Compiling $inUsePackagesDescription" -PercentComplete (($releasesProgress / $releasesCount) * 100)
-			Write-Verbose "Requesting deployment process snapshot for release $releasesProgress of $releasesCount"
-			$releaseInUsePackages = Get-InUsePackages -Release $release
-			foreach ($key in $releaseInUsePackages.Keys) {
-				# no need to record this package if it was already recorded via another release
-				if (!$inUsePackages[$key]) {
-					$inUsePackages[$key] = $releaseInUsePackages[$key]
-				}
-			}
-		}
-		Write-Verbose "Saving $inUsePackagesDescription"
-		$inUsePackages | Export-Clixml $inUsePackagesCacheFile -Force -WhatIf:$false -Confirm:$false
-	}
-
-	Write-Host 'Querying Octopus for feeds'
-	$octopusRepository.Feeds.FindAll() `
-		| ? { $_.FeedType -eq [Octopus.Client.Model.FeedType]::NuGet } `
-		| % { $script:AllFeeds[$_.Id] = $_ }
-
-	$inUsePackagesAsArray = New-Object 'Octopus.Client.Model.PackageResource[]' $inUsePackages.Values.Count
-	$i=0; $inUsePackages.Values | % { $inUsePackagesAsArray[$i] = [Octopus.Client.Model.PackageResource]$_; $i++ }
-	$allFeedsAsArray = New-Object 'Octopus.Client.Model.NugetFeedResource[]' $script:AllFeeds.Values.Count
-	$i=0; $script:AllFeeds.Values | % { $allFeedsAsArray[$i] = [Octopus.Client.Model.NugetFeedResource]$_; $i++ }
-	Test-PackagesWentMissingAfterPreviousRunStarted -Packages $inUsePackagesAsArray -Feeds $allFeedsAsArray
-
-	$inUsePackageNamesWithHighestVersion = New-Object 'System.Collections.Generic.Dictionary[string,Octopus.Client.Model.SemanticVersion]'
-	foreach ($inUsePackage in $inUsePackages.Values) {
-		if ((!$inUsePackageNamesWithHighestVersion[$inUsePackage.PackageId]) `
-			-or ((New-Object 'Octopus.Client.Model.SemanticVersion' $inUsePackage.Version) `
-				-gt $inUsePackageNamesWithHighestVersion[$inUsePackage.PackageId])
-			) {
-			$inUsePackageNamesWithHighestVersion[$inUsePackage.PackageId] = New-Object 'Octopus.Client.Model.SemanticVersion' $inUsePackage.Version
-		}
-	}
-	$inUseFeedIds = @($inUsePackages.Values | Select-Object -Property FeedId -Unique | % { $_.FeedId })
-	Write-Host 'Evaluating and processing feeds'
-	$script:AllFeeds.Keys | ? { $inUseFeedIds -notcontains $_ } | % {
-		Write-Verbose "Skipping feed '$_' ($($script:AllFeeds[$_].FeedUri)). It is not associated with any packages from any releases."
-	}
-	foreach ($inUseFeedId in $inUseFeedIds) {
-		if (Test-FeedId -FeedId $inUseFeedId) {
-			Write-Host "Processing feed '$inUseFeedId' ($($script:AllFeeds[$inUseFeedId].FeedUri))."
-			$packagesOnFeed = Get-PackageIdAndVersion -Feed $script:AllFeeds[$inUseFeedId] -PublishedNoLaterThan $publishedNoLaterThan
-			foreach ($packageOnFeed in $packagesOnFeed) {
-				# Parse and validate $packageOnFeed, which should be a package ID and version separated by a dot
-				$packageName = ''
-				$packageVersion = $null
-				if (![Octopus.Client.Util.PackageIdentityParser]::TryParsePackageIdAndVersion(
-					$packageOnFeed, [ref]$packageName, [ref]$packageVersion)) {
-					throw "The output from Nuget packages API did not consist of a valid package ID and version: '$packageOnFeed'"
-				}
-				$preserveMessage = "Preserving package $packageOnFeed on $($script:AllFeeds[$inUseFeedId].FeedUri)"
-				if ($inUsePackageNamesWithHighestVersion.ContainsKey($packageName)) {
-					$hash = [string]::Join(' ', @($inUseFeedId, $packageName, $packageVersion.ToNormalizedString()))
-					if ($inUsePackages.ContainsKey($hash)) {
-						Write-Verbose "$preserveMessage. It is associated with an Octopus release."
-					} elseif ($packageVersion -gt $inUsePackageNamesWithHighestVersion[$packageName]) { # uses semantic comparison operator override
-						Write-Verbose "$preserveMessage. Its version ($($packageVersion.ToNormalizedString())) is higher than the highest version of '$packageName' associated with an Octopus release ($($inUsePackageNamesWithHighestVersion[$packageName])), so it may have been published for a future release."
-					} else {
-						Remove-Package -Feed $script:AllFeeds[$inUseFeedId] -PackageName $packageName -PackageVersion $packageVersion
-					}
-				} else {
-					Write-Verbose "$preserveMessage. No package named '$packageName' is associated with an Octopus release, so it may have been published for a future release."
-				}
-			}
-		}
-	}
-}
-
-if ($VerbosePreference -eq 'SilentlyContinue') { 
-	$script:NugetVerbosity = 'quiet' 
-} else {
-	$script:NugetVerbosity = 'normal' 
-}
-AcquireAssemblies
-LoadAssemblies
-$script:AllFeeds = New-Object 'System.Collections.Generic.Dictionary[string,Octopus.Client.Model.NuGetFeedResource]'
-$script:ExcludedFeedIds = @()
-$script:IncludedFeedIds = @()
-if (!(Test-Path $PathToStoreDataAcrossRuns -PathType Container)) {
-	New-Item -Path $PathToStoreDataAcrossRuns -ItemType 'directory' -Force  -WhatIf:$false -Confirm:$false
-}
-PurgeNugetFeeds
diff --git a/Octopus.Client/PowerShell/Feeds/Remove-PackageVersionsNotUsedByOctopus.ps1 b/Octopus.Client/PowerShell/Feeds/Remove-PackageVersionsNotUsedByOctopus.ps1
new file mode 100644
index 00000000..cb638562
--- /dev/null
+++ b/Octopus.Client/PowerShell/Feeds/Remove-PackageVersionsNotUsedByOctopus.ps1
@@ -0,0 +1,885 @@
+<#
+
+.SYNOPSIS
+Important: Tested for deployment packages on ProGet (https://inedo.com/proget) NuGet feeds. When
+using with other feed providers, set -DoDeletes $False to test-- it may turn out to be necessary to add a
+variation of the Get-PackageOnFeed function.
+
+Deletes from one or more feeds any package meeting all of these criteria:
+ - ID in Octopus release(s) or runbook snapshot(s)
+ - version not in Octopus release(s) or runbook snapshot(s)
+ - published more than a specified timespan ago
+
+Generates a .txt summary. Example:
+  Feed 'https://foo.com/nuget/foo/v3/index.json' package counts:
+   - 21251 total
+   - 64 to retain because published after 11/16/2021 18:04:57 -05:00
+   - 7803 to retain because no version of package ID referenced by any Octopus Release or Runbook Snapshot
+   - 13384 will now be checked against package versions referenced by Octopus...
+    - 266 to retain because referenced by Octopus Release(s) or Runbook Snapshot(s)
+    - 13118 to delete because published more than 720 hours ago and Releases or Runbook Snapshots reference other versions of the package's ID but not the package's own version
+  Feed 'https://bar.com/nuget/bar/v3/index.json' package counts:
+  [...]
+
+Generates a .csv report with one row for every package version on the specified feed(s) and these columns:
+ - Author
+ - DetailsUri
+ - DownloadUri
+ - Id
+ - NormalizedVersion
+ - Published
+ - FeedUri
+ - HoursSincePublished
+ - Delete (TRUE or FALSE)
+ - Reason -- one of the following:
+  - "delete because published more than [specified] hours ago and Releases or Runbook Snapshots reference other versions of the package's ID but not the package's own version"
+  - "retain because no Release references any version of this package ID"
+  - "retain because published within the past 720 hours"
+  - "retain because referenced by Release(s) or Runbook Snapshot(s)"
+ - ReferencedByReleasesOrRunbookSnapshots ("NA" or newline-separated URLs)
+
+ Generates a .csv deletions report with one row for every attempted package deletion
+ - Author
+ - DetailsUri
+ - DownloadUri
+ - Id
+ - NormalizedVersion
+ - Published
+ - FeedUri
+ - HoursSincePublished
+ - DeleteSucceeded
+ - TimeDeletedOrAttempted
+
+.PARAMETER DoDeletes
+Required. Boolean. Report files are generated regardless of value but packages are deleted only if True.
+Value must be $True, $False, 0 (equivalent to $False) or a number greater than 0 (equivalent to $True)
+Example:
+-DoDeletes $True
+
+.PARAMETER FeedApiKeys
+Required. Hashtable of NuGet feed URLs and API keys, Example:
+-FeedApiKeys @{'https://foo/feedA/v3/index.json' = 'foO0key'; 'https://foo/feedB/v3/index.json' = 'bArk3y'}
+
+.PARAMETER OctopusApiKey
+Required.
+
+.PARAMETER OctopusUri
+Required. Example:
+-OctopusUri 'https://octopus.foo.com/api'
+
+.PARAMETER PreserveRecentPackagesThresholdInHours
+The script will ignore packages with Published timestamps less than this many hours before the start of the
+script run. Decimals are allowed.
+Default: 720 (30 days)
+Example:
+-PreserveRecentPackagesThresholdInHours ([int]([timespan]::FromDays(60).TotalHours))
+
+.PARAMETER ReportFolder
+The full path to a folder where files about the script run can be written before being added to Octopus as
+artifacts
+
+.PARAMETER NugetExePath
+Local path where nuget.exe is present or to which this script will download it
+Default: 'c:\temp\nuget-commandline\nuget.exe'
+
+.PARAMETER NugetExeUrl
+URL from which this script will download nuget.exe if not already present at NugetExePath
+Default: 'https://dist.nuget.org/win-x86-commandline/latest/nuget.exe'
+
+.PARAMETER FeedForOctopusAssemblies
+Feed from which this script will download the Octopus Deploy packages Octopus.Client and Octostache, and their
+dependencies.
+Default: 'https://api.nuget.org/v3/index.json'
+
+.PARAMETER NugetRequestTimeoutInSeconds
+Number of seconds before queries for lists of packages from nuget feeds time out.
+Default: 30
+
+.NOTES
+TODO: Add support for parallel deletes if running in PowerShell 7.1+
+
+.OUTPUTS
+None, but generates report files. See Synopsis for details.
+
+.EXAMPLE
+. .\Remove-PackageVersionsNotUsedByOctopus.ps1 `
+  -DoDeletes $True `
+  -FeedApiKeys @{'https://foo/feedA/v3/index.json' = 'foO0key'; 'https://foo/feedB/v3/index.json' = 'bArk3y'} `
+  -OctopusApiKey 'FOO API KEY' `
+  -OctopusUri 'https://octopus.foo.com/api' `
+  -PreserveRecentPackagesThresholdInHours ([int]([timespan]::FromDays(30).TotalHours)) `
+  -Verbose
+
+#>
+[CmdletBinding()] # Enable -Verbose switch
+[Diagnostics.CodeAnalysis.SuppressMessageAttribute('PSUseApprovedVerbs', '', Scope='Function')]
+Param(
+	[parameter(Mandatory = $true)][bool]$DoDeletes,
+	[parameter(Mandatory = $true)][hashtable]$FeedApiKeys,
+	[parameter(Mandatory = $true)][string]$OctopusApiKey,
+	[parameter(Mandatory = $true)][string]$OctopusUri,
+	[parameter(Mandatory = $false)][int]$PreserveRecentPackagesThresholdInHours = ([int]([timespan]::FromDays(30).TotalHours)),
+	[parameter(Mandatory = $false)][string]$ReportFolder = (Join-Path $PWD 'Reports'),
+	[parameter(Mandatory = $false)][string]$NugetExePath = 'c:\temp\nuget-commandline\nuget.exe',
+	[parameter(Mandatory = $false)][string]$NugetExeUrl = 'https://dist.nuget.org/win-x86-commandline/latest/nuget.exe',
+	[parameter(Mandatory = $false)][string]$FeedForOctopusAssemblies = 'https://api.nuget.org/v3/index.json',
+	[parameter(Mandatory = $false)][int]$NugetRequestTimeoutInSeconds = 30
+)
+Set-StrictMode -Version 3
+$ErrorActionPreference = 'Stop'
+Write-Host "Executing script: $(Split-Path -Path $PSCommandPath -Leaf)"
+Write-Host "Executing on $($env:COMPUTERNAME) as $(& whoami)"
+if ($PSBoundParameters['Debug']) {
+	$DebugPreference = 'Continue' # avoid Inquire
+}
+[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12
+
+Write-Host "`$VerbosePreference`: $($VerbosePreference)"
+Write-Host "`$OctopusUri`: $OctopusUri"
+Write-Host "`$OctopusApiKey`: $([string]::new('*', $OctopusApiKey.Length))"
+Write-Host "`$PreserveRecentPackagesThresholdInHours`: $PreserveRecentPackagesThresholdInHours"
+
+foreach ($feedUri in $FeedApiKeys.Keys) {
+	Write-Host "`$FeedApiKeys['$feedUri']`: $([string]::new('*', $FeedApiKeys[$feedUri].Length))"
+	if (-not [uri]::IsWellFormedUriString($feedUri, [System.UriKind]::Absolute)) {
+		throw [System.FormatException]::new("Feed URI is not in a valid format: $feedUri")
+	}
+	Write-Host "Testing Feed URI '$feedUri'"
+	$statusCode = (Invoke-WebRequest $feedUri -UseBasicParsing -Verbose:$false).StatusCode
+	if ($statusCode -ne 200) {
+		throw "Status code was '$statusCode' rather than 200. Requested Feed URI '$feedUri' from computer '$env:COMPUTERNAME'."
+	}
+}
+
+if (Test-Path Function:\Update-Progress) {
+	function Write-Progress {
+		[CmdletBinding()]
+		[Diagnostics.CodeAnalysis.SuppressMessageAttribute('PSAvoidOverwritingBuiltInCmdlets', '', Justification = 'For Octopus Deploy context')]
+		param(
+			[string]$Activity,
+			[string]$CurrentOperation,
+			[int] $PercentComplete,
+			[int] $SecondsRemaining
+		)
+  
+		process {
+			$message = $Activity
+			if ($CurrentOperation) {
+				$message += " / $CurrentOperation"
+			}
+			if ($SecondsRemaining) {
+				$message += " - $([System.TimeSpan]::FromSeconds($SecondsRemaining).ToString('g')) remaining"
+			}
+			Update-Progress -Percentage $PercentComplete -Message $message
+		}
+	}
+}
+
+# Adapted from (ASD's own SO answer) https://stackoverflow.com/questions/5565029/check-if-full-path-given/35046453#35046453
+function IsFullPath {
+	[CmdletBinding()]
+	[OutputType([bool])]
+	Param(
+		[parameter()][string]$Path
+	)
+	( `
+	(-not [string]::IsNullOrWhiteSpace($Path)) `
+		-and $Path.IndexOfAny([System.IO.Path]::GetInvalidPathChars()) -eq -1 `
+		-and [System.IO.Path]::IsPathRooted($Path) `
+		-and (-not [System.IO.Path]::GetPathRoot($Path).Equals([System.IO.Path]::DirectorySeparatorChar.ToString(), [StringComparison]::Ordinal)) `
+		-and (-not [System.IO.Path]::GetPathRoot($Path).EndsWith([System.IO.Path]::VolumeSeparatorChar)) `
+		)
+}
+
+if (-not (IsFullPath $ReportFolder)) {
+	throw [System.ArgumentException]::new("ReportFolder must be a file system absolute path. Value: '$ReportFolder'", 'ReportFolder')
+}
+if (!(Test-Path $ReportFolder -PathType Container)) {
+	New-Item -Path $ReportFolder -ItemType 'directory' -Force -WhatIf:$false -Confirm:$false | Out-Null
+	Write-Host "Created ReportFolder $ReportFolder"
+}
+
+function Get-NugetExe {
+	[CmdletBinding()]
+	[OutputType([System.IO.FileInfo])]
+	Param()
+	if ((Test-Path $NugetExePath -PathType Leaf)) {
+		Write-Host "'$NugetExePath' exists; no need to download"
+	} else {
+		Write-Host "'$NugetExePath' does not exist. Downloading from '$NugetExeUrl'"
+		$nugetExeFolder = [System.IO.Path]::GetDirectoryName($NugetExePath)
+		if (-not (Test-Path $nugetExeFolder -PathType Container)) {
+			mkdir $nugetExeFolder | Out-Null
+		}
+		Invoke-WebRequest $NugetExeUrl -OutFile $NugetExePath -UseBasicParsing -Verbose:$false
+	}
+	[System.IO.FileInfo](Get-Item $NugetExePath)
+}
+
+function Get-OctopusAssemblies {
+	[CmdletBinding()]
+	[OutputType([System.Void])]
+	Param(
+		[parameter()][System.IO.DirectoryInfo]$NugetOutputDirectory,
+		[parameter()][System.IO.FileInfo]$NugetExe
+	)
+	Write-Host "Acquiring packages containing Octopus assemblies from feed '$FeedForOctopusAssemblies'"
+	Write-Host " - Will use '$($NugetExe.FullName)'"
+	Write-Host " - Will extract to '$($NugetOutputDirectory.FullName)'"
+	@('Octopus.Client', 'Octostache') | ForEach-Object { 
+		. $NugetExe.FullName install $_ -Source $FeedForOctopusAssemblies -OutputDirectory $NugetOutputDirectory.FullName -ExcludeVersion -PackageSaveMode nuspec -Framework net40 -Verbosity $script:NugetVerbosity -NonInteractive | Out-Null
+	}
+}
+
+function Load-OctopusAssemblies {
+	[CmdletBinding()]
+	[OutputType([System.Void])]
+	Param(
+		[parameter()][System.IO.DirectoryInfo]$NugetOutputDirectory,
+		[parameter()][switch]$CheckExistingOnly
+	)
+	if ($CheckExistingOnly.IsPresent) {
+		Write-Host 'Checking whether Octopus assemblies are already present'
+	} else {
+		Write-Host 'Consolidating Octopus assemblies'
+	}
+	$markdigLibParentPath = Join-Path $NugetOutputDirectory.FullName 'Markdig\lib'
+	$destination = Join-Path $NugetOutputDirectory.FullName 'Octostache\lib\net40\'
+	foreach ($path in $NugetOutputDirectory.FullName, $destination, $markdigLibParentPath) {
+		if (-not (Test-Path $path -PathType Container)) {
+			$message = "Folder '$path' not found"
+			if ($CheckExistingOnly.IsPresent) {
+				Write-Verbose $message
+				return $false
+			} else {
+				throw [System.IO.DirectoryNotFoundException]::new($message)
+			}
+		}
+	}
+	$markdigLibPath = Get-ChildItem $markdigLibParentPath -Filter 'net4*' | Where-Object { $_.PSIsContainer } | Sort-Object Name -Descending | Select-Object -First 1 | ForEach-Object { $_.FullName }
+	if (-not $markdigLibPath) {
+		$message = "Did not find a folder matching '$(Join-Path $markdigLibParentPath 'net4*')'"
+		if ($CheckExistingOnly.IsPresent) {
+			Write-Verbose $message
+			return $false
+		} else {
+			throw [System.IO.DirectoryNotFoundException]::new($message)
+		}
+	}
+	$markdigPath = Join-Path $markdigLibPath 'Markdig.dll'
+	$sprachePath = Join-Path $NugetOutputDirectory.FullName 'Sprache\lib\net40\Sprache.dll'
+	foreach ($path in $markdigPath, $sprachePath) {
+		$assemblyName = (Split-Path $path -Leaf)
+		if ((Test-Path -LiteralPath (Join-Path $destination $assemblyName) -PathType Leaf)) {
+			if (-not $CheckExistingOnly.IsPresent) {
+				Write-Verbose "Octopus assembly '$assemblyName' is already present in '$destination'"
+			}
+		} else {
+			if ($CheckExistingOnly.IsPresent) {
+				return $false
+			} else {
+				Copy-Item $path $destination -WhatIf:$false
+			}
+		}
+	}
+	if ($CheckExistingOnly.IsPresent) {
+		return $true
+	}
+	Write-Host 'Loading Octopus assemblies'
+	@(
+		'Newtonsoft.Json\lib\net40\Newtonsoft.Json.dll',
+		'Octopus.Client\lib\net462\Octopus.Client.dll',
+		'Octostache\lib\net40\Octostache.dll'
+	) | ForEach-Object { 
+		Add-Type -Path (Join-Path $NugetOutputDirectory.FullName $_)
+	}
+}
+
+function Get-InUsePackages {
+	[CmdletBinding()] # Enable -Verbose switch
+	[OutputType('System.Collections.Generic.Dictionary[string, Octopus.Client.Model.PackageResource]')]
+	Param ( 
+		[parameter(Mandatory = $true)][Octopus.Client.Model.ISnapshotResource]$RunbookSnapshotOrRelease
+	)
+	$packageVersions = @{ }
+	foreach ($selectedPackage in $RunbookSnapshotOrRelease.SelectedPackages) {
+		$packageVersions[$selectedPackage.ActionName] = $selectedPackage.Version
+	}
+	$headers = @{ "X-Octopus-ApiKey" = $OctopusApiKey }
+	if ([bool]$RunbookSnapshotOrRelease.PSObject.Properties['ProjectDeploymentProcessSnapshotId']) {
+		$snapshotType = 'deploymentprocesses'
+		$processSnapshotId = $RunbookSnapshotOrRelease.ProjectDeploymentProcessSnapshotId
+	} else {
+		$snapshotType = 'runbookProcesses'
+		$processSnapshotId = $RunbookSnapshotOrRelease.FrozenRunbookProcessId
+	}
+	$uri = [string]::Join('/', @(
+			$OctopusUri.TrimEnd('/'), 
+			$RunbookSnapshotOrRelease.SpaceId,
+			$snapshotType, 
+			$processSnapshotId)
+	)
+	if (-not (Test-Path variable:script:CachedResponses)) {
+		$script:CachedResponses = @{}
+	}
+	if ($script:CachedResponses.ContainsKey($uri)) {
+		$processSnapshot = $script:CachedResponses[$uri]
+	} else {
+		#Write-Verbose "Process snapshot URI: $uri"
+		$progPref = $ProgressPreference
+		$ProgressPreference = 'SilentlyContinue'
+		try {
+			$processSnapshot = Invoke-RestMethod -Uri $uri -Headers $headers -Method Get -Verbose:$false
+		} catch {
+			Write-Warning "Request to process snapshot URI '$uri' failed"
+			throw
+		}
+		$ProgressPreference = $progPref
+		$script:CachedResponses.Add($uri, $processSnapshot)
+	}
+
+	$selectedPackageVersions = New-Object 'System.Collections.Generic.Dictionary[string,Octopus.Client.Model.PackageResource]'
+	foreach ($step in $processSnapshot.Steps) {
+		foreach ($action in $step.Actions) {
+			if ((!$action.IsDisabled) -and $packageVersions[$action.Name] -and $action.ActionType -ne 'Octopus.DeployRelease') {
+				foreach ($package in $action.Packages) {
+					$packageDiagnosticText = "($($RunbookSnapshotOrRelease.SpaceId)/$($package.FeedId))/$(($OctopusUri -replace '/api$') + $RunbookSnapshotOrRelease.Links.Self)"
+					$selectedPackageVersion = New-Object 'Octopus.Client.Model.PackageResource'
+					$packageIDResult = Get-PackageId -RunbookSnapshotOrRelease $RunbookSnapshotOrRelease -PossibleOctostacheExpression $package.PackageId
+					if (-not $packageIDResult.DefinitelyFullyResolved) {
+						Write-Warning "'$($package.PackageId)' evaluated to '$($packageIDResult.Evaluated)'. $packageDiagnosticText"
+						if (-not (Test-Path variable:script:CachedResponses)) {
+							$script:CachedResponses = @{}
+						}
+					}
+					$selectedPackageVersion.PackageId = $selectedPackageVersion.Id = `
+						$selectedPackageVersion.Title = $packageIDResult.Evaluated
+					try {
+						$normalizedVersion = `
+							[Octopus.Client.Model.SemanticVersion]::new($packageVersions[$action.Name]).ToNormalizedString()
+					} catch {
+						throw [System.FormatException]::new("Unable to normalize version number '$($packageVersions[$action.Name])' of '$($package.PackageId)' from $packageDiagnosticText. Exception was: $_", $_.Exception)
+					}
+					$selectedPackageVersion.Version = $normalizedVersion
+					$packageHash = [string]::Join(' ', @($selectedPackageVersion.PackageId, $selectedPackageVersion.Version))
+					$selectedPackageVersions[$packageHash] = $selectedPackageVersion
+				}
+			}
+		}
+	}
+	$selectedPackageVersions
+}
+
+<#
+	.SYNOPSIS
+	Get-PackageId attempts to evaluate an Octostache expression from a release's or runbook snapshot's
+	deployment process snapshot using the corresponding variable snapshots.
+	
+	Get-PackageId was implemented to address this scenario: Some process steps may define Octostache expressions 
+	for the names of packages, for example to define different package names to use depending on a release's 
+	channel. Unfortunately, process snapshots contain only the octostache variable name, not the evaluated
+	package name (even though the dynamically-selected package version is recorded alongside it).
+	
+	Processing accounts for channels.
+#>
+function Get-PackageId {
+	[CmdletBinding()] # Enable -Verbose switch
+	Param (
+		[parameter(Mandatory = $true)][Octopus.Client.Model.ISnapshotResource]$RunbookSnapshotOrRelease,
+		[parameter(Mandatory = $true)][string]$PossibleOctostacheExpression
+	)
+	if ([Octostache.VariableDictionary]::CanEvaluationBeSkippedForExpression($PossibleOctostacheExpression)) {
+		[PSCustomObject]@{
+			Evaluated               = $PossibleOctostacheExpression
+			DefinitelyFullyResolved = $true
+		}
+	} else {
+		#Write-Verbose "Attempting to evaluate possible Octostache expression '$PossibleOctostacheExpression'"
+		$headers = @{ "X-Octopus-ApiKey" = $OctopusApiKey }
+		if (-not (Test-Path variable:script:CachedResponses)) {
+			$script:CachedResponses = @{}
+		}
+		$uri = [string]::Join('/', @(
+				$OctopusUri.TrimEnd('/'), 
+				$RunbookSnapshotOrRelease.SpaceId,
+				'variables', 
+				$RunbookSnapshotOrRelease.ProjectVariableSetSnapshotId))
+		if ($script:CachedResponses.ContainsKey($uri)) {
+			$variableSetSnapshots = $script:CachedResponses[$uri]
+		} else {
+			$progPref = $ProgressPreference
+			$ProgressPreference = 'SilentlyContinue'
+			$variableSetSnapshots = @(Invoke-RestMethod -Uri $uri -Headers $headers -Method Get -Verbose:$false)
+			$ProgressPreference = $progPref
+			$script:CachedResponses.Add($uri, $variableSetSnapshots)
+		}
+		foreach ($libraryVariableSetSnapshotId in $RunbookSnapshotOrRelease.LibraryVariableSetSnapshotIds) {
+			$uri = [string]::Join('/', @(
+					$OctopusUri.TrimEnd('/'), 
+					$RunbookSnapshotOrRelease.SpaceId,
+					'variables', 
+					$libraryVariableSetSnapshotId)
+			)
+			if ($script:CachedResponses.ContainsKey($uri)) {
+				$variableSetSnapshots += $script:CachedResponses[$uri]
+			} else {
+				$progPref = $ProgressPreference
+				$ProgressPreference = 'SilentlyContinue'
+				$libraryVariableSetSnapshot = Invoke-RestMethod -Uri $uri -Headers $headers -Method Get -Verbose:$false
+				$variableSetSnapshots += $libraryVariableSetSnapshot
+				$ProgressPreference = $progPref
+				$script:CachedResponses.Add($uri, $libraryVariableSetSnapshot)
+			}
+		}
+		$snapshottedVariables = New-Object 'Octostache.VariableDictionary'
+		foreach ($variableSetSnapshot in $variableSetSnapshots) {
+			foreach ($variable in $variableSetSnapshot.Variables) {
+				if (
+					((-not $RunbookSnapshotOrRelease.ChannelId) -or (-not $variable.Scope) -or (-not $variable.Scope.psobject.Properties['Channel'])) `
+						-or `
+					($variable.Scope.psobject.Properties['Channel'] -and $variable.Scope.Channel.Contains($RunbookSnapshotOrRelease.ChannelId))
+				) {
+					$snapshottedVariables[$variable.Name] = $variable.Value
+				}
+			}
+		}
+		#Write-Verbose "'$PossibleOctostacheExpression' evaluated to '$evaluated'"
+		$result = [PSCustomObject]@{
+			Evaluated               = $snapshottedVariables.Evaluate($PossibleOctostacheExpression)
+			DefinitelyFullyResolved = $false
+		}
+		if ([Octostache.VariableDictionary]::CanEvaluationBeSkippedForExpression($result.Evaluated)) {
+			$result.DefinitelyFullyResolved = $true
+		}
+		$result
+	}
+}
+
+function Get-PackageOnFeed {
+	[CmdletBinding()]
+	Param(
+		[parameter(Mandatory = $true)][string]$FeedUri,
+		[parameter(Mandatory = $true)][System.DateTimeOffset]$PublishedNoLaterThan,
+		[parameter(Mandatory = $true)][System.Collections.Generic.HashSet[string]]$IncludeIds
+	)
+	# We consume the nuget API directly because of the following shortcomings of various API clients.
+	# - NuGet CLI (list command from nuget.exe or NuGet.Commands.ListCommandRunner from
+	#   nuget.client.dll): data corrpution possible due to wrapping of output if, for example,
+	#   WindowsSize.Width or BufferSize.Width is less than the combined length of the package ID and version.
+	#   refs:
+	#   https://github.com/NuGet/NuGet.Client/blob/3803820961f4d61c06d07b179dab1d0439ec0d91/src/NuGet.Clients/NuGet.CommandLine/Common/Console.cs#L264
+	#   https://github.com/NuGet/NuGet.Client/blob/dev/src/NuGet.Core/NuGet.Commands/ListCommand/ListCommandRunner.cs#L154
+	# - PackageManagement PowerShell module (Find-Package): not available on all environments; requires
+	#   PowerShell 5.0
+	# - Package Manager Console: Lacks a command to list packages without specifying a package ID
+
+	$v2FeedUri = $FeedUri -replace '/v3/index.json$'
+	$uri = [string]::Join('/', @(
+			$v2FeedUri.TrimEnd('/'), 
+			'Packages?$skip=0&$select=Id,NormalizedVersion,Published&$orderby=Id,NormalizedVersion&$filter=Listed%20eq%20true')
+	) # ref: https://www.odata.org/documentation/odata-version-2-0/uri-conventions/
+	$toBeChecked = [System.Collections.Generic.Dictionary[string, PSCustomObject]]::new()
+	$retainedBecausePublishedRecently = [System.Collections.Generic.Dictionary[string, PSCustomObject]]::new()
+	$retainedBecauseIDNotUsedByOctopus = [System.Collections.Generic.Dictionary[string, PSCustomObject]]::new()
+	$resultPage = 1
+	do {
+		$progPref = $ProgressPreference
+		$ProgressPreference = 'SilentlyContinue'
+		$response = Invoke-WebRequest -Uri $uri -Method Get -TimeoutSec $NugetRequestTimeoutInSeconds -UseBasicParsing -Verbose:$false
+		$ProgressPreference = $progPref
+		Write-Progress -Activity "Parsing page $($resultPage++;$resultPage) of packages on $v2FeedUri"
+		foreach ($packageEntry in ([xml]($response.Content)).feed.entry) {
+			$author = $packageEntry.author.name
+			$detailsUri = $packageEntry.id
+			$downloadUri = $packageEntry.content.src
+			$id = $packageEntry.title.InnerText
+			$normalizedVersion = $packageEntry.properties.NormalizedVersion
+			$published = [System.DateTimeOffset]::Parse($packageEntry.properties.Published.InnerText)
+			$package = [PSCustomObject]@{
+				Author              = $author
+				DetailsUri          = $detailsUri
+				DownloadUri         = $downloadUri
+				ID                  = $id
+				Published           = $published
+				NormalizedVersion   = $normalizedVersion
+				HoursSincePublished = [System.Math]::Round($inUsePackageInfo.QueryStartTime.Subtract($published).TotalHours, 1)
+			}
+			$packageHash = [string]::Join(' ', @($id, $normalizedVersion))
+			if (-not $IncludeIds.Contains($id)) {
+				$retainedBecauseIDNotUsedByOctopus[$packageHash] = $package
+			} elseif ($published -gt $PublishedNoLaterThan) {
+				$retainedBecausePublishedRecently[$packageHash] = $package
+			} else {
+				$toBeChecked[$packageHash] = $package
+			}
+		}
+		$uri = ([xml]($response.Content)).feed.link | Where-Object { $_.rel -eq 'next' } | ForEach-Object { $_.href }
+	} while ($uri)
+	#Write-Progress -Activity "Parsing packages on $v2FeedUri" -Completed
+	[PSCustomObject]@{
+		RetainedBecauseIDNotUsedByOctopus = $retainedBecauseIDNotUsedByOctopus
+		RetainedBecausePublishedRecently  = $retainedBecausePublishedRecently
+		ToBeChecked                       = $toBeChecked
+	}
+}
+
+<#
+
+.SYNOPSIS
+Throws if any required  system-level permissions are not present.
+refs:
+https://octopus.com/docs/security/users-and-teams/system-and-space-permissions
+https://octopus.com/docs/security/users-and-teams/default-permissions#DefaultPermissions-SystemManager
+https://octopus.com/docs/security/users-and-teams/default-permissions#DefaultPermissions-SpaceManager
+
+#>
+function Test-Permissions {
+	[CmdletBinding()] # Enable -Verbose switch
+	Param (
+		[parameter(Mandatory = $true)][Octopus.Client.OctopusRepository]$OctopusRepository
+	)
+
+	$requiredSystemPermissions = @('SpaceView')
+	$requiredSpacePermissions = @('ProjectView', 'ProcessView', 'VariableView',
+		'VariableViewUnscoped', 'ReleaseView', 'LibraryVariableSetView',
+		'ActionTemplateView', 'TenantView', 'RunbookView', 'RunbookRunView')
+
+	$currentUser = $OctopusRepository.Users.GetCurrent()
+	$uniqueIdentifyingClaims = $currentUser.Identities | ForEach-Object { $_.Claims.Keys | ForEach-Object { 
+			$currentUser.Identities[0].Claims[$_] } | Where-Object { $_.IsIdentifyingClaim } } | 
+		Select-Object Value -Unique | ForEach-Object { $_.Value }
+	Write-Host "Connected to Octopus as: " +
+	"$($currentUser | Select-Object Username, DisplayName, EmailAddress, Id); " +
+	"Provider Claims=$($uniqueIdentifyingClaims -join ', ')"
+	$userPermissionSet = $OctopusRepository.UserPermissions.Get($currentUser)
+	foreach ($requiredPermission in $requiredSystemPermissions) {
+		if (-not $userPermissionSet.SystemPermissions.Contains($requiredPermission)) {
+			throw [System.Security.SecurityException]::new("Identity lacks the $requiredPermission system permission")
+		}
+	}
+	$spaces = $octopusRepository.Spaces.GetAll()
+	foreach ($requiredPermission in $requiredSpacePermissions) {
+		$spacePermissions = $userPermissionSet.SpacePermissions[$requiredPermission]
+		foreach ($space in $spaces) {
+			$checkPassed = $false
+			foreach ($spacePermission in $spacePermissions) {
+				if ($spacePermission.SpaceId -eq $space.Id -and
+					($spacePermission.RestrictedToProjectIds.Contains('projects-all') -or
+					$spacePermission.RestrictedToProjectIds.Contains('projects-unrelated'))) {
+					$checkPassed = $true
+					break
+				}
+			}
+			if (-not $checkPassed) {
+				throw [System.Security.SecurityException]::new("Identity lacks the $requiredPermission permission in space $($space.Name)")
+			}
+		}
+	}
+}
+
+function Remove-Package {
+	[CmdletBinding()] # Enable -Verbose switch
+	[OutputType([bool])]
+	Param(
+		[parameter(Mandatory = $true)][string]$FeedUri,
+		[parameter(Mandatory = $true)][string]$ApiKey,
+		[parameter(Mandatory = $true)][string]$PackageID,
+		[parameter(Mandatory = $true)][string]$PackageVersion
+	)
+	$operation = "Deleting package '$PackageID $PackageVersion'"
+	#Write-Host "$operation from feed $FeedUri"
+	try {
+		Write-Host "##octopus[stderr-progress]"
+		. $nugetExe delete $PackageID $PackageVersion -Source $FeedUri -ApiKey $ApiKey -Verbosity detailed -NonInteractive | Out-Null
+		$nugetExeSucceeded = $?
+	} catch {
+		$nugetExeSucceeded = $false
+	} finally {
+		Write-Host "##octopus[stderr-default]"
+		if (-not $nugetExeSucceeded) {
+			Write-Warning "nuget.exe failed during this operation: $operation"
+			Write-Warning 'There may be verbose log output with additional details'
+		}
+	}
+	$nugetExeSucceeded
+}
+
+function New-ReportRow {
+	[CmdletBinding()] # Enable -Verbose switch
+	Param (
+		[parameter(Mandatory = $true)][string]$FeedUri,
+		[parameter(Mandatory = $true)]$Package,
+		[parameter(Mandatory = $true)][string]$Reason,
+		[parameter(Mandatory = $true)][bool]$Delete,
+		[parameter(Mandatory = $false)]$ReferencedByReleasesOrRunbookSnapshots
+	)
+	if ($ReferencedByReleasesOrRunbookSnapshots) {
+		$Links = ($ReferencedByReleasesOrRunbookSnapshots | ForEach-Object { ($OctopusUri -replace '/api$') + $_.Links.Self } ) -join "`n"
+	} else {
+		$Links = 'NA'
+	}
+	[PSCustomObject]@{
+		Author               = $Package.Author
+		DetailsUri           = $Package.DetailsUri
+		DownloadUri          = $Package.DownloadUri
+		Id                   = $Package.Id
+		NormalizedVersion    = $Package.NormalizedVersion
+		Published            = $Package.Published
+		FeedUri              = $FeedUri
+		HoursSincePublished  = $Package.HoursSincePublished
+		Delete               = $Delete
+		Reason               = $Reason
+		ReferencedByReleasesOrRunbookSnapshots = $Links
+	}
+}
+
+function New-DeletionsReportRow {
+	[CmdletBinding()] # Enable -Verbose switch
+	Param (
+		[parameter(Mandatory = $true)][string]$FeedUri,
+		[parameter(Mandatory = $true)]$Package,
+		[parameter(Mandatory = $true)][bool]$DeleteSucceeded,
+		[parameter(Mandatory = $true)][System.DateTimeOffset]$TimeDeletedOrAttempted
+	)
+	[PSCustomObject]@{
+		DeleteSucceeded        = $DeleteSucceeded
+		TimeDeletedOrAttempted = $TimeDeletedOrAttempted
+		Author                 = $Package.Author
+		DetailsUri             = $Package.DetailsUri
+		DownloadUri            = $Package.DownloadUri
+		Id                     = $Package.Id
+		NormalizedVersion      = $Package.NormalizedVersion
+		Published              = $Package.Published
+		FeedUri                = $FeedUri
+		HoursSincePublished    = $Package.HoursSincePublished
+	}
+}
+
+if ($VerbosePreference -eq 'SilentlyContinue') { 
+	$script:NugetVerbosity = 'quiet' 
+} else {
+	$script:NugetVerbosity = 'normal' 
+}
+$reportFile = Join-Path $ReportFolder (
+	[string]::Concat(@(
+			[System.IO.Path]::GetFileNameWithoutExtension($PSCommandPath),
+			' report ',
+		([datetime]::Now.ToString('u') -replace ':'),
+			'.csv'
+		)
+	)
+)
+$summaryFile = [System.IO.Path]::ChangeExtension(
+	($reportFile -replace ' report ', ' summary '),
+	'.txt'
+)
+$deletionsReportFile = $reportFile -replace ' report ', ' deletions '
+$summaryFile, $reportFile, $deletionsReportFile | ForEach-Object {
+	if (Test-Path $_) {
+		throw "File already exists: $_"
+	}
+}
+$nugetExe = Get-NugetExe
+if ((Load-OctopusAssemblies -CheckExistingOnly -NugetOutputDirectory $nugetExe.Directory) -eq $true) {
+	Write-Verbose 'Octopus assembly packages are already downloaded and extracted'
+} else {
+	Get-OctopusAssemblies -NugetExe $nugetExe -NugetOutputDirectory $nugetExe.Directory
+}
+Load-OctopusAssemblies -NugetOutputDirectory $nugetExe.Directory
+$octopusRepository = (New-Object Octopus.Client.OctopusRepository (New-Object Octopus.Client.OctopusServerEndpoint $OctopusURI, $OctopusApiKey))
+Test-Permissions -OctopusRepository $octopusRepository
+$inUsePackagesDescription = 'list of packages associated with Octopus releases or runbook snapshots'
+$inUsePackageInfo = [PSCustomObject]@{
+	Packages       = [System.Collections.Generic.Dictionary[string, PSCustomObject]]::new()
+	PackageIds     = [System.Collections.Generic.HashSet[string]]::new()
+	QueryStartTime = [System.DateTimeOffset]::Now
+	QueryEndTime   = [System.DateTimeOffset]::MaxValue # placeholder
+}
+Write-Host 'Querying Octopus for Spaces'
+$headers = @{ "X-Octopus-ApiKey" = $OctopusApiKey }
+$uri = [string]::Join('/', @(
+		$OctopusUri.TrimEnd('/'), 
+		'spaces',
+		'all'))
+$progPref = $ProgressPreference
+$ProgressPreference = 'SilentlyContinue'
+$spaces = Invoke-RestMethod -Uri $uri -Headers $headers -Method Get -Verbose:$false
+$ProgressPreference = $progPref
+$releasesAndRunbookSnapshots = @()
+$spaces | ForEach-Object {
+	$space = [Octopus.Client.Model.SpaceResource]::new()
+	$space.Id = $_.Id
+	$space.Name = $_.Name
+	$space.IsDefault = $_.IsDefault
+	$space.Links = [Octopus.Client.Extensibility.LinkCollection]::new()
+	$space.Links.Add('SpaceHome', [Octopus.Client.Extensibility.Href]::new($_.Links.SpaceHome)) | Out-Null
+	$spaceClient = $octopusRepository.Client.ForSpace($space)
+	Write-Host "Querying Octopus for releases in $($space.Id) ($($space.Name))"
+	$releasesAndRunbookSnapshots += $spaceClient.Releases.FindAll()
+	Write-Host "Querying Octopus for runbook snapshots in $($space.Id) ($($space.Name))"
+	$releasesAndRunbookSnapshots += $spaceClient.RunbookSnapshots.FindAll()
+}
+Write-Host "Compiling $inUsePackagesDescription"
+$releasesAndRunbookSnapshotsCount = $releasesAndRunbookSnapshots.Count
+$releasesOrRunbookSnapshotsStartTime = [System.DateTimeOffset]::Now
+$releasesOrRunbookSnapshotsProgress = 0
+foreach ($releaseOrRunbookSnapshot in $releasesAndRunbookSnapshots) {
+	$proportionComplete = $releasesOrRunbookSnapshotsProgress / $releasesAndRunbookSnapshotsCount
+	if ($releasesOrRunbookSnapshotsProgress -eq 0) {
+		$secondsRemaining = -1
+	} else {
+		$secondsElapsed = [System.DateTimeOffset]::Now.Subtract($releasesOrRunbookSnapshotsStartTime).TotalSeconds
+		$estimatedSeconds = $secondsElapsed / $proportionComplete
+		$secondsRemaining = $estimatedSeconds - $secondsElapsed
+	}
+	Write-Progress -Activity "Compiling $inUsePackagesDescription" `
+		-PercentComplete ($proportionComplete * 100) `
+		-SecondsRemaining $secondsRemaining
+	#Write-Verbose "Requesting deployment process snapshot for release or runbook snapshot $releasesOrRunbookSnapshotsProgress of $releasesAndRunbookSnapshotsCount with ID $($releaseOrRunbookSnapshot.id)"
+	$inUsePackages = Get-InUsePackages -RunbookSnapshotOrRelease $releaseOrRunbookSnapshot
+	foreach ($key in $inUsePackages.Keys) {
+		if ($inUsePackages[$key].PackageId -eq '') {
+			throw "The process snapshot for '$($releaseOrRunbookSnapshot.id)' references a package with an ID that evaluates to empty string (''). The package's version is '$($inUsePackages[$key].Version)'"
+		}
+		$inUsePackageInfo.PackageIds.Add($inUsePackages[$key].PackageId) | Out-Null
+		if (!$inUsePackageInfo.Packages[$key]) {
+			$inUsePackageInfo.Packages[$key] = [PSCustomObject]@{
+				Package  = $inUsePackages[$key]
+				ReleasesOrRunbookSnaphots = @($releaseOrRunbookSnapshot)
+			}
+		} else {
+			$inUsePackageInfo.Packages[$key].ReleasesOrRunbookSnaphots += $releaseOrRunbookSnapshot
+		}
+	}
+	$releasesOrRunbookSnapshotsProgress++
+}
+$inUsePackageInfo.QueryEndTime = [System.DateTimeOffset]::Now
+#Write-Progress -Activity "Compiling $inUsePackagesDescription" -PercentComplete 100 -Completed
+$publishedNoLaterThan = $inUsePackageInfo.QueryStartTime.Subtract( `
+		[System.TimeSpan]::FromHours($PreserveRecentPackagesThresholdInHours))
+$inUsePackageInfoQueryMinutes = [System.Math]::Round($inUsePackageInfo.QueryEndTime.Subtract( `
+			$inUsePackageInfo.QueryStartTime).TotalMinutes, 1)
+Write-Verbose "It took $inUsePackageInfoQueryMinutes minutes to compile $inUsePackagesDescription"
+
+$summaryReportLines = @(
+	"How we will determine which packages were published too recently to consider deleting:",
+	" - PreserveRecentPackagesThresholdInHours is set to $PreserveRecentPackagesThresholdInHours.",
+	" - The $inUsePackagesDescription was pulled from Octopus beginning $($inUsePackageInfo.QueryStartTime).",
+	" - So packages published after $publishedNoLaterThan will not be considered for deletion."
+)
+$summaryReportLines | Write-Host
+$summaryReportLines | Out-File $summaryFile -Append
+
+$packagesToDelete = @{}
+$feedUris = $FeedApiKeys.Keys
+try {
+	foreach ($feedUri in $feedUris) {
+		$packagesOnFeed = Get-PackageOnFeed -FeedUri $feedUri -PublishedNoLaterThan $publishedNoLaterThan -IncludeIds $inUsePackageInfo.PackageIds
+		$totalPackagesOnFeed = (
+			$packagesOnFeed.ToBeChecked.Count + `
+				$packagesOnFeed.RetainedBecausePublishedRecently.Count + `
+				$packagesOnFeed.RetainedBecauseIDNotUsedByOctopus.Count
+		)
+		$summaryReportLines = @(
+			'',
+			"Feed '$feedUri' package counts:",
+			" - $totalPackagesOnFeed total",
+			" - $($packagesOnFeed.RetainedBecausePublishedRecently.Count) to retain because published after $PublishedNoLaterThan",
+			" - $($packagesOnFeed.RetainedBecauseIDNotUsedByOctopus.Count) to retain because no version of package ID referenced by any Octopus Release or Runbook Snapshot",
+			" - $($packagesOnFeed.ToBeChecked.Count) will now be checked against package versions referenced by Octopus..."
+		)
+		$summaryReportLines | Write-Host
+		$summaryReportLines | Out-File $summaryFile -Append
+		$packagesOnFeedReferencedByOctopus = [System.Collections.Generic.Dictionary[string, PSCustomObject]]::new()
+		$packagesToDelete.Add($feedUri, [System.Collections.Generic.Dictionary[string, PSCustomObject]]::new())
+		foreach ($packageId_VersionOnFeed in $packagesOnFeed.ToBeChecked.Keys) {
+			if ($inUsePackageInfo.Packages.Keys.Contains($packageId_VersionOnFeed)) {
+				$packagesOnFeedReferencedByOctopus.Add($packageId_VersionOnFeed, $packagesOnFeed.ToBeChecked[$packageId_VersionOnFeed])
+			} else {
+				$packagesToDelete[$feedUri].Add($packageId_VersionOnFeed, $packagesOnFeed.ToBeChecked[$packageId_VersionOnFeed])
+			}
+		}
+		$deleteReason = "published more than $PreserveRecentPackagesThresholdInHours hours ago and Releases or Runbook Snapshots reference other versions of the package's ID but not the package's own version"
+		$summaryReportLines = @(
+			"  - $($packagesOnFeedReferencedByOctopus.Count) to retain because referenced by Octopus Release(s) or Runbook Snapshot(s)",
+			"  - $($packagesToDelete[$feedUri].Count) to delete because $deleteReason"
+		)
+		$summaryReportLines | Write-Host
+		$summaryReportLines | Out-File $summaryFile -Append
+
+		$reportRows = [System.Collections.Generic.List[PSCustomObject]]::new()
+		foreach ($package in $packagesOnFeed.RetainedBecausePublishedRecently.Values) {
+			$reason = "retain because published within the past $PreserveRecentPackagesThresholdInHours hours"
+			$reportRows.Add((New-ReportRow -FeedUri $feedUri -Package $package -Reason $reason -Delete $false))
+		}
+		foreach ($package in $packagesOnFeed.RetainedBecauseIDNotUsedByOctopus.Values) {
+			$reason = 'retain because no Release or Runbook Snapshot references any version of this package ID'
+			$reportRows.Add((New-ReportRow -FeedUri $feedUri -Package $package -Reason $reason -Delete $false))
+		}
+		foreach ($package in $packagesOnFeedReferencedByOctopus.Values) {
+			$reason = 'retain because referenced by Release(s) or Runbook Snapshot(s)'
+			$packageInfoFromOctopus = $inUsePackageInfo.Packages[([string]::Join(' ', @($package.ID, $package.NormalizedVersion)))]
+			$reportRows.Add((New-ReportRow -FeedUri $feedUri -Package $package -Reason $reason -ReferencedByReleasesOrRunbookSnapshots $packageInfoFromOctopus.ReleasesOrRunbookSnaphots -Delete $false))
+		}	
+		foreach ($package in $packagesToDelete[$feedUri].Values) {
+			$reason = "delete because $deleteReason"
+			$reportRows.Add((New-ReportRow -FeedUri $feedUri -Package $package -Reason $reason -Delete $true))
+		}
+		$reportRows | Export-Csv $reportFile -NoTypeInformation -Append -WhatIf:$false -Confirm:$false
+	}
+} finally {
+	if (Test-Path Function:\New-OctopusArtifact) {
+		New-OctopusArtifact	-FullPath $summaryFile -Name 'summary.txt'
+		New-OctopusArtifact	-FullPath $reportFile -Name 'details.csv'
+		Set-OctopusVariable -name 'Summary' -value ([string]::Join("`n", (Get-Content $summaryFile)))
+	} else {
+		Write-Host "PACKAGES REPORT: ""$reportFile"""
+		Write-Host "PACKAGES SUMMARY: ""$summaryFile"""
+	}
+}
+
+if ($DoDeletes) {
+	$deletionsReportRows = [System.Collections.Generic.List[PSCustomObject]]::new()
+	$packageCount = ($packagesToDelete.Values | Measure-Object -Sum -Property 'Count').Sum
+	$activity = "Deleting $packageCount packages $deleteReason"
+	$deletionsStartTime = [System.DateTimeOffset]::Now
+	$deletionsProgress = 0
+	try {
+		foreach ($feedUri in $feedUris) {
+			$currentOperation = "Deleting from '$feedUri'"
+			foreach ($package in $packagesToDelete[$feedUri].Values) {
+				$proportionComplete = $deletionsProgress / $packageCount
+				if ($deletionsProgress -eq 0) {
+					$secondsRemaining = -1
+				} else {
+					$secondsElapsed = [System.DateTimeOffset]::Now.Subtract($deletionsStartTime).TotalSeconds
+					$estimatedSeconds = $secondsElapsed / $proportionComplete
+					$secondsRemaining = $estimatedSeconds - $secondsElapsed
+				}
+				Write-Progress -Activity $activity -CurrentOperation $currentOperation `
+					-PercentComplete ($proportionComplete * 100) `
+					-SecondsRemaining $secondsRemaining
+				$deleteSucceeded = Remove-Package -FeedUri $feedUri -ApiKey $FeedApiKeys[$feedUri] -PackageID $package.ID -PackageVersion ([Octopus.Client.Model.SemanticVersion]::new($package.NormalizedVersion))
+				$deletionsReportRows.Add((New-DeletionsReportRow -FeedUri $feedUri -Package $package `
+							-DeleteSucceeded $deleteSucceeded -TimeDeletedOrAttempted ([DateTimeOffset]::Now)
+					))
+				$deletionsProgress++				
+			}
+			$deletionsReportRows | Export-Csv $deletionsReportFile -NoTypeInformation -Append -WhatIf:$false -Confirm:$false
+			$deletionsReportRows.Clear()
+		}
+	} finally {
+		#Write-Progress -Activity $activity -PercentComplete ($proportionComplete * 100)
+		Write-Host "Deletions finished in $([System.DateTimeOffset]::Now.Subtract($deletionsStartTime).ToString('g'))"
+		if (Test-Path $deletionsReportFile -PathType Leaf) {
+			if (Test-Path Function:\New-OctopusArtifact) {
+				New-OctopusArtifact -FullPath $deletionsReportFile -Name 'deletions.csv'
+			} else {
+				Write-Host "DELETIONS REPORT: ""$deletionsReportFile"""
+			}
+		} else {
+			Write-Warning "Deletions report not found (expected path: ""$deletionsReportFile"")"
+		}
+	}
+}
+Write-Host "Script finished in $([System.DateTimeOffset]::Now.Subtract($inUsePackageInfo.QueryStartTime).ToString('g'))"