diff --git a/var/spack/repos/builtin/packages/libtomlc99/package.py b/var/spack/repos/builtin/packages/libtomlc99/package.py
new file mode 100644
index 0000000000000000000000000000000000000000..3055bba12ef198e3c8de8fb68fa3cd2f9a5cd07f
--- /dev/null
+++ b/var/spack/repos/builtin/packages/libtomlc99/package.py
@@ -0,0 +1,33 @@
+# Copyright 2013-2019 Lawrence Livermore National Security, LLC and other
+# Spack Project Developers. See the top-level COPYRIGHT file for details.
+#
+# SPDX-License-Identifier: (Apache-2.0 OR MIT)
+
+from spack import *
+
+
+class Libtomlc99(Package):
+    """TOML in c99; v0.4.0 compliant."""
+
+    homepage = "https://github.com/cktan/tomlc99"
+    git      = "https://github.com/cktan/tomlc99.git"
+
+    # Since there is no official versioning, yet, just use the date and prefix
+    # with '0.' to make switching to proper versioning easier later.
+    # Unfortunately, upstream Makefile does not build shared libaries, so use
+    # local changes for now.
+    version('0.2019.05.02', commit='35118431263dec2a2a7b55e4dd717a5f54992e3e',
+            sha256sum='f131679131c1fcb012004a3334abb2b77a329490549c4d68455ba4ec55af9b10',
+            git="https://github.com/obreitwi/tomlc99.git")
+    # Does not build shared libraries.
+    version('0.2019.03.06', commit='bd76f1276ee5f5df0eb064f1842af5ad1737cf1e')
+
+    variant('debug', default=False, description="Build with debug enabled.")
+
+    def install(self, spec, prefix):
+        make_args = []
+        if spec.satisfies("+debug"):
+            make_args.append("DEBUG=1")
+
+        make(*make_args)
+        make('prefix={0}'.format(prefix), 'install')