diff --git a/+stdlib/+fileio/md5sum.m b/+stdlib/+fileio/md5sum.m
index 3c4d2f9..edd0c2d 100644
--- a/+stdlib/+fileio/md5sum.m
+++ b/+stdlib/+fileio/md5sum.m
@@ -5,19 +5,17 @@
   file (1,1) string {mustBeFile}
 end
 
-file = stdlib.fileio.expanduser(file);
-
 if ismac
-  [stat,hash] = system("md5 -r " + file);
+  [stat, hash] = system("md5 -r " + file);
 elseif isunix
-  [stat,hash] = system("md5sum " + file);
+  [stat, hash] = system("md5sum " + file);
 elseif ispc
-  [stat,hash] = system("CertUtil -hashfile " + file + " MD5");
+  [stat, hash] = system("CertUtil -hashfile " + file + " MD5");
 else
   error("no sha256sum method for your OS")
 end
 
-assert(stat == 0, hash)
+assert(stat == 0, hash, "failed to compute md5sum of " + file)
 
 hash = regexp(hash,'^\w{32}','match','once','lineanchors');
 hash = string(hash);
diff --git a/+stdlib/+fileio/sha256sum.m b/+stdlib/+fileio/sha256sum.m
index 46be8e8..40db1e8 100644
--- a/+stdlib/+fileio/sha256sum.m
+++ b/+stdlib/+fileio/sha256sum.m
@@ -4,19 +4,17 @@
   file (1,1) string {mustBeFile}
 end
 
-file = stdlib.fileio.expanduser(file);
-
 if ismac
-  [stat,hash] = system("shasum --algorithm 256 --binary " + file);
+  [stat, hash] = system("shasum --algorithm 256 --binary " + file);
 elseif isunix
-  [stat,hash] = system("sha256sum --binary " + file);
+  [stat, hash] = system("sha256sum --binary " + file);
 elseif ispc
-  [stat,hash] = system("CertUtil -hashfile " + file + " SHA256");
+  [stat, hash] = system("CertUtil -hashfile " + file + " SHA256");
 else
-  error("no md5sum method for your OS")
+  error("no sha256sum method for your OS")
 end
 
-assert(stat == 0, hash)
+assert(stat == 0, hash, "failed to compute SHA256 hash of " + file)
 
 hash = regexp(hash,'^\w{64}','match','once','lineanchors');
 hash = string(hash);
diff --git a/+stdlib/+hdf5nc/h5ndims.m b/+stdlib/+hdf5nc/h5ndims.m
index 3cda9b4..6de2ff1 100644
--- a/+stdlib/+hdf5nc/h5ndims.m
+++ b/+stdlib/+hdf5nc/h5ndims.m
@@ -10,7 +10,7 @@
   return
 end
 
-dsi = h5info(stdlib.fileio.expanduser(file), variable).Dataspace;
+dsi = h5info(file, variable).Dataspace;
 if dsi.Type == "scalar"
   frank = 0;
 else
diff --git a/+stdlib/+hdf5nc/h5size.m b/+stdlib/+hdf5nc/h5size.m
index 058a0fb..5013963 100644
--- a/+stdlib/+hdf5nc/h5size.m
+++ b/+stdlib/+hdf5nc/h5size.m
@@ -5,7 +5,7 @@
   variable (1,1) string {mustBeNonzeroLengthText}
 end
 
-dsi = h5info(stdlib.fileio.expanduser(file), variable).Dataspace;
+dsi = h5info(file, variable).Dataspace;
 if dsi.Type == "scalar"
   fsize = [];
 else
diff --git a/+stdlib/+hdf5nc/h5variables.m b/+stdlib/+hdf5nc/h5variables.m
index e8e10f9..5880b80 100644
--- a/+stdlib/+hdf5nc/h5variables.m
+++ b/+stdlib/+hdf5nc/h5variables.m
@@ -8,9 +8,9 @@
 names = string.empty;
 
 if isempty(group) || strlength(group) == 0
-  finf = h5info(stdlib.fileio.expanduser(file));
+  finf = h5info(file);
 else
-  finf = h5info(stdlib.fileio.expanduser(file), group);
+  finf = h5info(file, group);
 end
 
 ds = finf.Datasets;
diff --git a/+stdlib/+hdf5nc/ncndims.m b/+stdlib/+hdf5nc/ncndims.m
index 3e048c2..1862711 100644
--- a/+stdlib/+hdf5nc/ncndims.m
+++ b/+stdlib/+hdf5nc/ncndims.m
@@ -10,7 +10,7 @@
   return
 end
 
-dsi = ncinfo(stdlib.fileio.expanduser(file), variable);
+dsi = ncinfo(file, variable);
 if isempty(dsi.Dimensions)
   frank = 0;
 else
diff --git a/+stdlib/+hdf5nc/ncsize.m b/+stdlib/+hdf5nc/ncsize.m
index bac86e8..4b1c5bb 100644
--- a/+stdlib/+hdf5nc/ncsize.m
+++ b/+stdlib/+hdf5nc/ncsize.m
@@ -5,7 +5,7 @@
   variable (1,1) string {mustBeNonzeroLengthText}
 end
 
-dsi = ncinfo(stdlib.fileio.expanduser(file), variable);
+dsi = ncinfo(file, variable);
 if isempty(dsi.Dimensions)
   fsize = [];
 else
diff --git a/+stdlib/+hdf5nc/ncvariables.m b/+stdlib/+hdf5nc/ncvariables.m
index 50ab67c..6f5b56e 100644
--- a/+stdlib/+hdf5nc/ncvariables.m
+++ b/+stdlib/+hdf5nc/ncvariables.m
@@ -8,9 +8,9 @@
 names = string.empty;
 
 if isempty(group) || strlength(group) == 0
-  finf = ncinfo(stdlib.fileio.expanduser(file));
+  finf = ncinfo(file);
 else
-  finf = ncinfo(stdlib.fileio.expanduser(file), group);
+  finf = ncinfo(file, group);
 end
 
 ds = finf.Variables(:);
diff --git a/+stdlib/+sys/diskfree.m b/+stdlib/+sys/diskfree.m
index 0468a73..fc24d67 100644
--- a/+stdlib/+sys/diskfree.m
+++ b/+stdlib/+sys/diskfree.m
@@ -1,15 +1,11 @@
 function freebytes = diskfree(direc)
 %% diskfree(direc)
 % returns disk free space in bytes
-% example:  diskfree('~')
+% example:  diskfree('/')
 arguments
-  direc (1,1) string
+  direc (1,1) string {mustBeFolder}
 end
 
-direc = stdlib.fileio.expanduser(direc);
-
-assert(isfolder(direc), '%s is not a folder', direc)
-
 freebytes = java.io.File(direc).getUsableSpace;
 
 end
diff --git a/+stdlib/+test/TestIntg.m b/+stdlib/+test/TestIntg.m
index 4f10e08..adc5d45 100644
--- a/+stdlib/+test/TestIntg.m
+++ b/+stdlib/+test/TestIntg.m
@@ -11,8 +11,8 @@ function test_checkRAM(tc)
 function test_diskfree(tc)
 tc.assumeTrue(usejava("jvm"), "Java required for path_tail")
 
-tc.assertTrue(isnumeric(stdlib.sys.diskfree('~')))
-tc.assertTrue(stdlib.sys.diskfree('~') > 0, 'diskfree')
+tc.assertTrue(isnumeric(stdlib.sys.diskfree('/')))
+tc.assertTrue(stdlib.sys.diskfree('/') > 0, 'diskfree')
 end
 
 function test_memory(tc)
diff --git a/Readme.md b/Readme.md
index 6cf951d..dcc6447 100644
--- a/Readme.md
+++ b/Readme.md
@@ -1,4 +1,4 @@
-# Matlab standard library
+# Standard library for Matlab
 
 [![DOI](https://zenodo.org/badge/273830124.svg)](https://zenodo.org/badge/latestdoi/273830124)
 [![View matlab-hdf5 on File Exchange](https://www.mathworks.com/matlabcentral/images/matlab-file-exchange.svg)](https://www.mathworks.com/matlabcentral/fileexchange/78673-matlab-hdf5)