diff --git a/lib/LaTeXML/Util/Test.pm b/lib/LaTeXML/Util/Test.pm
index 6b49d3201..43be8d555 100644
--- a/lib/LaTeXML/Util/Test.pm
+++ b/lib/LaTeXML/Util/Test.pm
@@ -86,12 +86,14 @@ sub check_requirements {
     next unless $reqmts;
     my @required_packages = ();
     my $texlive_min       = 0;
+    my $required_env;
     if (!(ref $reqmts)) {
       @required_packages = ($reqmts); }
     elsif (ref $reqmts eq 'ARRAY') {
       @required_packages = @$reqmts; }
     elsif (ref $reqmts eq 'HASH') {
       @required_packages = (ref $$reqmts{packages} eq 'ARRAY' ? @{ $$reqmts{packages} } : $$reqmts{packages});
+      $required_env      = $$reqmts{env};
       $texlive_min       = $$reqmts{texlive_min} || 0; }
     foreach my $reqmt (@required_packages) {
       if (pathname_kpsewhich($reqmt) || pathname_find($reqmt)) { }
@@ -105,6 +107,11 @@ sub check_requirements {
       my $message = "Minimal texlive $texlive_min requirement not met for $test";
       diag("Skip: $message");
       skip($message, $ntests);
+      return 0; }
+    elsif ($required_env && !$ENV{$required_env}) {
+      my $message = "$test is only checked in continuous integration. (use make test CI=true)";
+      diag("Skip: $message");
+      skip($message, $ntests);
       return 0; } }
   return 1; }
 
diff --git a/t/50_structure.t b/t/50_structure.t
index 8d7b3cbcc..ab576bd31 100644
--- a/t/50_structure.t
+++ b/t/50_structure.t
@@ -9,5 +9,6 @@ latexml_tests("t/structure",
     amsarticle => 'amsart.cls',
     csquotes   => 'csquotes.sty',
     glossary   => {
+      env => 'CI', # only run in continuous integration
       texlive_min => 2016,
       packages    => 'glossaries.sty' } });
diff --git a/t/80_complex.t b/t/80_complex.t
index f6f2b4795..28918d36c 100644
--- a/t/80_complex.t
+++ b/t/80_complex.t
@@ -7,4 +7,6 @@ use LaTeXML::Util::Test;
 latexml_tests("t/complex",
   requires => {
     cleveref_minimal => 'cleveref.sty',
-    si               => { packages => 'siunitx.sty', texlive_min => 2015 } });
+    si               => {
+      env=>'CI', # only runs in continuous integration
+      packages => 'siunitx.sty', texlive_min => 2015 } });