diff --git a/var/spack/repos/builtin/packages/nseg/package.py b/var/spack/repos/builtin/packages/nseg/package.py
new file mode 100644
index 0000000000000000000000000000000000000000..ed5f903516f0d3a6dc23682347160c98e0a0c15b
--- /dev/null
+++ b/var/spack/repos/builtin/packages/nseg/package.py
@@ -0,0 +1,81 @@
+# 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 Nseg(MakefilePackage):
+    """NSEG - Low complexity sequence identification"""
+
+    homepage = "ftp://ftp.ncbi.nih.gov/pub/seg/nseg/"
+    url      = "ftp://ftp.ncbi.nih.gov/pub/seg/nseg/nseg.c"
+
+    version('1.0', sha256='afae364fbe51caa1eccb704ed0b954437a3ef48a0cd3bf473f4b61d6fde9617e',
+            expand=False)
+
+    resource(
+        name='makefile',
+        url="ftp://ftp.ncbi.nih.gov/pub/seg/nseg/makefile",
+        sha256='32937aef6969550ca3c762b5dd61b1520635cc46e773e35e56c5718f75838cee',
+        expand=False,
+    )
+
+    resource(
+        name='genwin.c',
+        url="ftp://ftp.ncbi.nih.gov/pub/seg/nseg/genwin.c",
+        sha256='d392d2db625dc8c90b00f2a86028a3a45d121e15eb403b51c2f9b01692ab10d9',
+        expand=False,
+    )
+
+    resource(
+        name='genwin.h',
+        url="ftp://ftp.ncbi.nih.gov/pub/seg/nseg/genwin.h",
+        sha256='1c701d87bf6200bfa40faa16fe665828a010727ef1aa0e8a1e5823605165fb86',
+        expand=False,
+    )
+
+    resource(
+        name='lnfac.h',
+        url="ftp://ftp.ncbi.nih.gov/pub/seg/nseg/lnfac.h",
+        sha256='5048e4f3dc3a7ea420d4eb4912a661f285634fbb205411b647b1f00c3fe3a0d2',
+        expand=False,
+    )
+
+    resource(
+        name='nmerge.c',
+        url="ftp://ftp.ncbi.nih.gov/pub/seg/nseg/nmerge.c",
+        sha256='c8a4bb4c960acf7fcd7509b635766b618efdab9f09aec36443040759eca3bce3',
+        expand=False,
+    )
+
+    resource(
+        name='runnseg',
+        url="ftp://ftp.ncbi.nih.gov/pub/seg/nseg/runnseg",
+        sha256='2830a5a1c5ea1a879cf3a415dfbb23db7a81e84d41698ddf765f2e1ef42e7c78',
+        expand=False,
+    )
+
+    build_directory = 'nseg'
+
+    @run_before('build')
+    def prepare_source(self):
+        # create the build dir
+        mkdirp(self.build_directory)
+
+        # move the primary source file in
+        copy('nseg.c', join_path(self.build_directory, 'nseg.c'))
+
+        # move all of the single-file resources into the build dir
+        for key in self.resources:
+            for res in self.resources[key]:
+                res_name = res.name
+                res_path = join_path(res.fetcher.stage.path, res.name)
+                copy(res_path, join_path(self.build_directory, res_name))
+
+    def install(self, spec, prefix):
+        with working_dir(self.build_directory):
+            mkdirp(prefix.bin)
+            install('nseg', prefix.bin)
+            install('nmerge', prefix.bin)