diff --git a/.github/workflows/osx.yml b/.github/workflows/osx.yml
deleted file mode 100644
index b170e795e..000000000
--- a/.github/workflows/osx.yml
+++ /dev/null
@@ -1,36 +0,0 @@
-name: Mathics (OSX)
-
-on:
-  push:
-    branches: [ master ]
-  pull_request:
-    branches: [ master ]
-
-jobs:
-  build:
-    env:
-      NO_CYTHON: 1
-    runs-on: macos-latest
-    strategy:
-      matrix:
-        os: [macOS]
-        python-version: [3.6, 3.7, 3.8, 3.9]
-    steps:
-    - uses: actions/checkout@v3
-    - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v2
-      with:
-        python-version: ${{ matrix.python-version }}
-    - name: Install dependencies
-      run: |
-        brew install llvm@11
-        python -m pip install --upgrade pip
-        LLVM_CONFIG=/usr/local/Cellar/llvm@11/11.1.0/bin/llvm-config pip install llvmlite
-        # Can remove after next Mathics-Scanner release
-        # python -m pip install -e git+https://github.com/Mathics3/mathics-scanner#egg=Mathics-Scanner[full]
-    - name: Install Mathics with full dependencies
-      run: |
-        make develop-full
-    - name: Test Mathics
-      run: |
-        make -j3 check
diff --git a/.github/workflows/ubuntu-cython.yml b/.github/workflows/ubuntu-cython.yml
deleted file mode 100644
index 19a990dcb..000000000
--- a/.github/workflows/ubuntu-cython.yml
+++ /dev/null
@@ -1,32 +0,0 @@
-name: Mathics (ubuntu full with Cython)
-
-on:
-  push:
-    branches: [ master ]
-  pull_request:
-    branches: [ master ]
-
-jobs:
-  build:
-    runs-on: ubuntu-20.04
-    strategy:
-      matrix:
-        python-version: [3.9]
-    steps:
-    - uses: actions/checkout@v3
-    - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v2
-      with:
-        python-version: ${{ matrix.python-version }}
-    - name: Install dependencies
-      run: |
-        sudo apt-get update -qq && sudo apt-get install -qq liblapack-dev llvm-dev
-        python -m pip install --upgrade pip
-        # Can remove after next Mathics-Scanner release
-        # python -m pip install -e git+https://github.com/Mathics3/mathics-scanner#egg=Mathics-Scanner[full]
-    - name: Install Mathics with full dependencies
-      run: |
-        make develop-full-cython
-    - name: Test Mathics
-      run: |
-        make -j3 check
diff --git a/.github/workflows/ubuntu-pyston.yml b/.github/workflows/ubuntu-pyston.yml
new file mode 100644
index 000000000..62bab8ed5
--- /dev/null
+++ b/.github/workflows/ubuntu-pyston.yml
@@ -0,0 +1,35 @@
+name: Mathics (ubuntu full with Pyston)
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  build:
+    runs-on: ubuntu-22.04
+    strategy:
+      matrix:
+        pyston-version: [2.3.4]
+    steps:
+    - uses: actions/checkout@v3
+    - name: Set up Pyston ${{ matrix.pyston-version }}
+      run: |
+        wget https://github.com/pyston/pyston/releases/download/pyston_2.3.4/pyston_2.3.4_20.04_amd64.deb
+        sudo apt-get install tk8.6-blt2.5 libffi7
+        sudo dpkg -i pyston_2.3.4_20.04_amd64.deb
+    - name: Install dependencies
+      run: |
+        sudo apt-get update -qq && sudo apt-get install -qq liblapack-dev llvm-11 llvm-11-dev
+        # sudo /usr/lib/llvm-11/bin/llvm-config --version
+        sudo pyston -m pip install --upgrade pip
+        sudo LLVM_CONFIG=/usr/lib/llvm-11/bin/llvm-config  pyston -m pip install llvmlite
+    - name: Install Mathics with minimal dependencies
+      run: |
+        make develop
+    - name: Test Mathics
+      run: |
+        # py.test seems to use always the default python interpreter of the system. Any idea about how to
+        # change this behaviour?
+        make -j3 PYTHON=pyston doctest
diff --git a/.github/workflows/ubuntu.yml b/.github/workflows/ubuntu.yml
deleted file mode 100644
index 7a8b7796c..000000000
--- a/.github/workflows/ubuntu.yml
+++ /dev/null
@@ -1,34 +0,0 @@
-name: Mathics (ubuntu)
-
-on:
-  push:
-    branches: [ master ]
-  pull_request:
-    branches: [ master ]
-
-jobs:
-  build:
-    env:
-      NO_CYTHON: 1
-    runs-on: ubuntu-20.04
-    strategy:
-      matrix:
-        python-version: [3.6, 3.7, 3.8, 3.9]
-    steps:
-    - uses: actions/checkout@v3
-    - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v2
-      with:
-        python-version: ${{ matrix.python-version }}
-    - name: Install dependencies
-      run: |
-        sudo apt-get update -qq && sudo apt-get install -qq liblapack-dev llvm-dev
-        python -m pip install --upgrade pip
-        # Can remove after next Mathics-Scanner release
-        # python -m pip install -e git+https://github.com/Mathics3/mathics-scanner#egg=Mathics-Scanner[full]
-    - name: Install Mathics with full dependencies
-      run: |
-        make develop-full
-    - name: Test Mathics
-      run: |
-        make -j3 check
diff --git a/.github/workflows/windows.yml b/.github/workflows/windows.yml
deleted file mode 100755
index e91bc7127..000000000
--- a/.github/workflows/windows.yml
+++ /dev/null
@@ -1,40 +0,0 @@
-name: Mathics (Windows)
-
-on:
-  push:
-    branches: [ master ]
-  pull_request:
-    branches: [ master ]
-
-jobs:
-  build:
-    env:
-      NO_CYTHON: 1
-    runs-on: windows-latest
-    strategy:
-      matrix:
-        os: [windows]
-        python-version: [3.7, 3.8]
-    steps:
-    - uses: actions/checkout@v3
-    - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v2
-      with:
-        python-version: ${{ matrix.python-version }}
-    - name: Install dependencies
-      run: |
-        python -m pip install --upgrade pip
-        python -m pip install wheel
-        choco install llvm
-        set LLVM_DIR="C:\Program Files\LLVM"
-        # Can remove after next Mathics-Scanner release
-        # python -m pip install -e git+https://github.com/Mathics3/mathics-scanner#egg=Mathics-Scanner[full]
-        pip install -e .
-    - name: Install Mathics
-      run: |
-        python setup.py install
-    - name: Test Mathics
-      run: |
-        pip install -e .[dev,full]
-        set PYTEST_WORKERS="-n3"
-        make check
diff --git a/mathics/algorithm/integrators.py b/mathics/algorithm/integrators.py
index 2466c4bee..dbb6818bb 100644
--- a/mathics/algorithm/integrators.py
+++ b/mathics/algorithm/integrators.py
@@ -229,3 +229,5 @@ def apply_D_to_Integral(func, domain, var, evaluation, options, head):
 }
 integrator_methods["Simpson"] = integrator_methods["Internal"]
 integrator_methods["Automatic"] = integrator_methods["Internal"]
+
+integrator_messages = {}
diff --git a/mathics/builtin/numbers/calculus.py b/mathics/builtin/numbers/calculus.py
index 6e7d953b0..8b9715974 100644
--- a/mathics/builtin/numbers/calculus.py
+++ b/mathics/builtin/numbers/calculus.py
@@ -1285,18 +1285,9 @@ class _BaseFinder(Builtin):
     This class is the basis class for FindRoot, FindMinimum and FindMaximum.
     """
 
-    options = {
-        "MaxIterations": "100",
-        "Method": "Automatic",
-        "AccuracyGoal": "Automatic",
-        "PrecisionGoal": "Automatic",
-        "StepMonitor": "None",
-        "EvaluationMonitor": "None",
-        "Jacobian": "Automatic",
-    }
-
     attributes = hold_all | protected
-
+    requires = ["scipy"]
+    methods = {}
     messages = {
         "snum": "Value `1` is not a number.",
         "nnum": "The function value is not a number at `1` = `2`.",
@@ -1313,7 +1304,15 @@ class _BaseFinder(Builtin):
         ),
     }
 
-    methods = {}
+    options = {
+        "MaxIterations": "100",
+        "Method": "Automatic",
+        "AccuracyGoal": "Automatic",
+        "PrecisionGoal": "Automatic",
+        "StepMonitor": "None",
+        "EvaluationMonitor": "None",
+        "Jacobian": "Automatic",
+    }
 
     def apply(self, f, x, x0, evaluation, options):
         "%(name)s[f_, {x_, x0_}, OptionsPattern[]]"
@@ -2048,6 +2047,7 @@ class NIntegrate(Builtin):
 
     """
 
+    requires = ["scipy"]
     summary_text = "numerical integration in one or several variables"
     messages = {
         "bdmtd": "The Method option should be a built-in method name.",
@@ -2077,6 +2077,7 @@ class NIntegrate(Builtin):
         "Automatic": (None, False),
     }
     try:
+        # builtin integrators
         from mathics.algorithm.integrators import (
             integrator_methods,
             integrator_messages,
@@ -2088,6 +2089,7 @@ class NIntegrate(Builtin):
         pass
 
     try:
+        # scipy integrators
         from mathics.builtin.scipy_utils.integrators import (
             scipy_nintegrate_methods,
             scipy_nintegrate_messages,
@@ -2096,11 +2098,9 @@ class NIntegrate(Builtin):
         methods.update(scipy_nintegrate_methods)
         messages.update(scipy_nintegrate_messages)
     except Exception as e:
-        print(e)
-        print("scipy integrators was not loaded.")
         pass
 
-    methods.update(
+    messages.update(
         {
             "bdmtd": "The Method option should be a "
             + "built-in method name in {`"
diff --git a/mathics/builtin/optiondoc.py b/mathics/builtin/optiondoc.py
index c49ccde1d..27f665222 100644
--- a/mathics/builtin/optiondoc.py
+++ b/mathics/builtin/optiondoc.py
@@ -176,10 +176,14 @@ class MaxRecursion(Builtin):
       <dd>is an option for functions like NIntegrate and Plot that specifies how many recursive subdivisions can be made.
     </dl>
 
-    >> NIntegrate[Exp[-10^8 x^2], {x, -1, 1}, MaxRecursion -> 10]
-     =  1.97519×10^-207
+    >> NIntegrate[Exp[-10^8 x^2], {x, -1, 1}, Method->"Internal", MaxRecursion -> 3]
+     =  0.0777778
+    >> NIntegrate[Exp[-10^8 x^2], {x, -1, 1}, Method->"Internal", MaxRecursion -> 6]
+     =  0.00972222
     """
 
+    # This test does not pass if scipy is not available...
+
     summary_text = "maximum number of recursive subdivisions"
 
 
diff --git a/mathics/doc/common_doc.py b/mathics/doc/common_doc.py
index b6ad88e52..dbf071825 100644
--- a/mathics/doc/common_doc.py
+++ b/mathics/doc/common_doc.py
@@ -138,6 +138,28 @@
 test_result_map = {}
 
 
+# TODO: Use this when checking requires for modules.
+requires_lib_cache = {}
+
+
+def check_requires_list(requires: list) -> bool:
+    global requires_cache
+
+    for package in requires:
+        lib_is_installed = requires_lib_cache.get(package, None)
+        if lib_is_installed is None:
+            lib_is_installed = True
+            try:
+                importlib.import_module(package)
+            except ImportError:
+                lib_is_installed = False
+            requires_lib_cache[package] = lib_is_installed
+
+        if not lib_is_installed:
+            return False
+    return True
+
+
 def get_results_by_test(test_expr: str, full_test_key: list, doc_data: dict) -> list:
     """
     Sometimes test numbering is off, either due to bugs or changes since the
@@ -665,6 +687,8 @@ def get_tests(self):
                                     # iterated below. Probably some other code is faulty and
                                     # when fixed the below loop and collection into doctest_list[]
                                     # will be removed.
+                                    if not docsubsection.installed:
+                                        continue
                                     doctest_list = []
                                     index = 1
                                     for doctests in docsubsection.items:
@@ -906,13 +930,8 @@ def add_section(
         object to the chapter, a DocChapter object.
         "section_object" is either a Python module or a Class object instance.
         """
-        installed = True
-        for package in getattr(section_object, "requires", []):
-            try:
-                importlib.import_module(package)
-            except ImportError:
-                installed = False
-                break
+        installed = check_requires_list(getattr(section_object, "requires", []))
+
         # FIXME add an additional mechanism in the module
         # to allow a docstring and indicate it is not to go in the
         # user manual
@@ -949,17 +968,12 @@ def add_subsection(
         operator=None,
         in_guide=False,
     ):
-        installed = True
-        for package in getattr(instance, "requires", []):
-            try:
-                importlib.import_module(package)
-            except ImportError:
-                installed = False
-                break
+        installed = check_requires_list(getattr(instance, "requires", []))
 
         # FIXME add an additional mechanism in the module
         # to allow a docstring and indicate it is not to go in the
         # user manual
+
         if not instance.__doc__:
             return
         subsection = DocSubsection(
@@ -1058,6 +1072,8 @@ def __init__(self, module=None):
                 and var.__module__[: len(self.pymathicsmodule.__name__)]
                 == self.pymathicsmodule.__name__
             ):  # nopep8
+                if not check_requires_list(var):
+                    continue
                 instance = var(expression=False)
                 if isinstance(instance, Builtin):
                     self.symbols[instance.get_name()] = instance
@@ -1105,13 +1121,7 @@ def __init__(self, module=None):
         chapter = DocChapter(builtin_part, title, XMLDoc(text))
         for name in self.symbols:
             instance = self.symbols[name]
-            installed = True
-            for package in getattr(instance, "requires", []):
-                try:
-                    importlib.import_module(package)
-                except ImportError:
-                    installed = False
-                    break
+            installed = check_requires_list(getattr(instance, "requires", []))
             section = DocSection(
                 chapter,
                 strip_system_prefix(name),
@@ -1329,8 +1339,12 @@ def get_tests(self):
         # A guide section's subsection are Sections without the Guide.
         # it is *their* subsections where we generally find tests.
         for section in self.subsections:
+            if not section.installed:
+                continue
             for subsection in section.subsections:
                 # FIXME we are omitting the section title here...
+                if not subsection.installed:
+                    continue
                 for doctests in subsection.items:
                     yield doctests.get_tests()