[[!comment format=mdwn
 username="joey"
 subject="""comment 3"""
 date="2019-03-06T22:11:45Z"
 content="""
Something like this (only tested it compiles):

	diff --git a/src/Propellor/Property/Sbuild.hs b/src/Propellor/Property/Sbuild.hs
	index 8cc2e3bec..25d5f6236 100644
	--- a/src/Propellor/Property/Sbuild.hs
	+++ b/src/Propellor/Property/Sbuild.hs
	@@ -29,6 +29,7 @@ Suggested usage in @config.hs@:
	 >    where
	 >  	sidSchrootBuilt = Sbuild.built Sbuild.UseCcache $ props
	 >  		& osDebian Unstable X86_32
	+>		& Sbuild.standard
	 >  		& Sbuild.update `period` Weekly (Just 1)
	 >  		& Sbuild.useHostProxy mybox
	 
	@@ -64,6 +65,7 @@ module Propellor.Property.Sbuild (
	 	built,
	 	-- * Properties for use inside sbuild schroots
 		update,
	+	standard,
 		useHostProxy,
 		-- * Global sbuild configuration
	 	-- blockNetwork,
	@@ -126,7 +128,7 @@ built'
	 	-> String
	 	-> String
	 	-> RevertableProperty (HasInfo + DebianLike) Linux
	-built' cc (Props ps) suite arch = provisioned <!> deleted
	+built' cc ps suite arch = provisioned <!> deleted
	   where
	 	provisioned :: Property (HasInfo + DebianLike)
	 	provisioned = combineProperties desc $ props
	@@ -220,10 +222,7 @@ built' cc (Props ps) suite arch = provisioned <!> deleted
	 
	 	-- the schroot itself
	 	schroot = Chroot.debootstrapped Debootstrap.BuilddD
	-			schrootRoot (Props schrootProps)
	-	schrootProps =
	-		ps ++ [toChildProperty Apt.stdSourcesList
	-		, toChildProperty $ Apt.installed ["eatmydata", "ccache"]]
	+			schrootRoot ps
	 
	 	-- static values
	 	suiteArch = suite ++ "-" ++ arch
	@@ -251,6 +250,14 @@ built' cc (Props ps) suite arch = provisioned <!> deleted
	 	  where
	 		base = ["eatmydata"]
	 
	+-- | Some properties that will be wanted in most any Debian schroot.
	+--
	+-- Compiler caching, eatmydata, and standard apt sources.
	+standard :: Property Debian
	+standard = propertyList "standard sbuild properties" $ props
	+	& Apt.stdSourcesList
	+	& Apt.installed ["eatmydata", "ccache"]
	+
	 -- | Ensure that an sbuild schroot's packages and apt indexes are updated
	 --
	 -- This replaces use of sbuild-update(1).
"""]]
