diff --git a/.drone.star b/.drone.star
index 22a127991..1dbd504ed 100644
--- a/.drone.star
+++ b/.drone.star
@@ -17,8 +17,8 @@ def main(ctx):
 
   things_to_test = [ "special_fun", "distribution_tests", "mp", "misc", "interpolators", "quadrature", "autodiff", "long-running-tests", "float128_tests" ]
   sanitizer_test = [ "special_fun", "distribution_tests", "misc", "interpolators", "quadrature", "float128_tests" ]
-  gnu_5_stds = [ "gnu++11" ]
-  gnu_6_stds = [ "gnu++11", "gnu++14" ]
+  gnu_5_stds = [ "gnu++11", "c++11" ]
+  gnu_6_stds = [ "gnu++11", "gnu++14", "c++11", "c++14" ]
   gnu_8_stds = [ "gnu++11", "gnu++14", "gnu++17" ]
   gnu_10_stds = [ "gnu++11", "gnu++14", "gnu++17", "gnu++20" ]
 
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 0e3576aed..608760207 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -147,7 +147,7 @@ jobs:
       fail-fast: false
       matrix:
         compiler: [ g++-9, g++-11, clang++-10 ]
-        standard: [ c++11, c++14, c++17, c++2a ]
+        standard: [ c++14, c++17, c++2a ]
     steps:
       - uses: actions/checkout@v2
         with:
@@ -209,8 +209,8 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        compiler: [ g++-6, clang++-6.0, g++-7, g++-8, clang++-7, clang++-8 ]
-        standard: [ c++11, c++14, c++17 ]
+        compiler: [ clang++-6.0, g++-7, g++-8, clang++-7, clang++-8 ]
+        standard: [ c++14, c++17 ]
         suite: [ float128_tests, special_fun, distribution_tests, misc, quadrature, mp, interpolators, autodiff, ../example//examples, ../tools ]
     steps:
       - uses: actions/checkout@v2
@@ -274,7 +274,7 @@ jobs:
       fail-fast: false
       matrix:
         toolset: [ clang ]
-        standard: [ 11, 14, 17, 20 ]
+        standard: [ 14, 17, 20 ]
         suite: [ float128_tests, special_fun, distribution_tests, misc, quadrature, mp, interpolators, autodiff, ../example//examples, ../tools ]
     steps:
       - uses: actions/checkout@v2
@@ -322,7 +322,7 @@ jobs:
       fail-fast: false
       matrix:
         toolset: [ gcc, msvc-14.0, msvc-14.2 ]
-        standard: [ 11, 14, 17 ]
+        standard: [ 14, 17 ]
         suite: [ float128_tests, special_fun, distribution_tests, misc, quadrature, mp, interpolators, autodiff, ../example//examples, ../tools ]
     steps:
       - uses: actions/checkout@v2
@@ -412,7 +412,7 @@ jobs:
       fail-fast: false
       matrix:
         compiler: [ g++-11 ]
-        standard: [ c++17 ]
+        standard: [ c++14, c++17 ]
         suite: [ float128_tests, special_fun, distribution_tests, misc, quadrature, mp, interpolators, autodiff, ../example//examples, ../tools ]
     env:
       TOOLSET: gcc
@@ -542,7 +542,7 @@ jobs:
       fail-fast: false
       matrix:
         compiler: [ g++-10 ]
-        standard: [ c++11, c++14, c++17, c++2a ]
+        standard: [ c++14, c++17, c++2a ]
         suite: [ float128_tests, special_fun, distribution_tests, misc, quadrature, interpolators, autodiff, ../example//examples, ../tools ]
     steps:
       - uses: actions/checkout@v2