Merge pull request #26 from NixOS/ci #21

Job	Run time
Determine GHC versions to test	32s
nix-build (ghc810)	58s
nix-build (ghc8107)	1m 0s
nix-build (ghc90)	59s
nix-build (ghc902)	59s
nix-build (ghc910)	59s
nix-build (ghc9101)	58s
nix-build (ghc912)	1m 6s
nix-build (ghc9121)	1m 8s
nix-build (ghc92)	57s
nix-build (ghc925)	1m 0s
nix-build (ghc926)	59s
nix-build (ghc927)	57s
nix-build (ghc928)	59s
nix-build (ghc94)	1m 1s
nix-build (ghc945)	1m 1s
nix-build (ghc946)	59s
nix-build (ghc947)	59s
nix-build (ghc948)	58s
nix-build (ghc96)	1m 1s
nix-build (ghc963)	59s
nix-build (ghc964)	1m 1s
nix-build (ghc965)	1m 0s
nix-build (ghc966)	57s
nix-build (ghc98)	59s
nix-build (ghc981)	58s
nix-build (ghc982)	1m 0s
nix-build (ghc983)	58s
nix-build (ghc984)	1m 0s
nix-build (ghcHEAD)	1m 5s
	29m 27s

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