diff --git a/var/spack/repos/builtin/packages/tar/package.py b/var/spack/repos/builtin/packages/tar/package.py
index f5995cb0076975984de2b324d05c1cd665b104dd..7b6313827fe89a773a32be69c6008c74db635e1e 100644
--- a/var/spack/repos/builtin/packages/tar/package.py
+++ b/var/spack/repos/builtin/packages/tar/package.py
@@ -25,11 +25,11 @@
 from spack import *
 
 
-class Tar(Package):
+class Tar(AutotoolsPackage):
     """GNU Tar provides the ability to create tar archives, as well as various
     other kinds of manipulation."""
     homepage = "https://www.gnu.org/software/tar/"
-    url      = "https://ftp.gnu.org/gnu/tar/tar-1.28.tar.gz"
+    url = "https://ftp.gnu.org/gnu/tar/tar-1.28.tar.gz"
 
     version('1.29', 'cae466e6e58c7292355e7080248f244db3a4cf755f33f4fa25ca7f9a7ed09af0')
     version('1.28', '6ea3dbea1f2b0409b234048e021a9fd7')
@@ -38,8 +38,3 @@ class Tar(Package):
     # https://github.com/Homebrew/homebrew-core/commit/aef9a1792de4648d0322b4b04d32287532f046bb
     # TODO: when=sys.platform=='darwin' ?
     patch('gnutar-configure-xattrs.patch', when='@1.28')
-
-    def install(self, spec, prefix):
-        configure("--prefix=%s" % prefix)
-        make()
-        make('install')
diff --git a/var/spack/repos/builtin/packages/zlib/package.py b/var/spack/repos/builtin/packages/zlib/package.py
index 6f4d8a5bb8e741aeb1e7ebd064d59a0d5d832337..dfe7b4fdc11ea8b69d0b0a7e91ee1eeabbff28ee 100644
--- a/var/spack/repos/builtin/packages/zlib/package.py
+++ b/var/spack/repos/builtin/packages/zlib/package.py
@@ -25,19 +25,11 @@
 from spack import *
 
 
-class Zlib(Package):
+class Zlib(AutotoolsPackage):
     """A free, general-purpose, legally unencumbered lossless
        data-compression library."""
 
     homepage = "http://zlib.net"
-    url      = "http://zlib.net/zlib-1.2.8.tar.gz"
+    url = "http://zlib.net/zlib-1.2.8.tar.gz"
 
     version('1.2.8', '44d667c142d7cda120332623eab69f40')
-
-    def install(self, spec, prefix):
-        configure('--prefix={0}'.format(prefix))
-
-        make()
-        if self.run_tests:
-            make('test')
-        make('install')