diff --git a/.github/workflows/basic-tests.yml b/.github/workflows/basic-tests.yml
index 54d5ee2c9b8..45cd7248d07 100644
--- a/.github/workflows/basic-tests.yml
+++ b/.github/workflows/basic-tests.yml
@@ -25,7 +25,7 @@ jobs:
       run: |
         sudo apt-get -o Acquire::Retries=3 update
         sudo apt-get -o Acquire::Retries=3 install *fftw3* mpi intel-mkl* git-lfs graphviz
-        pip install "tox<4.0.0" pip setuptools --upgrade
+        pip install tox pip setuptools --upgrade
     - name: installing auxiliary data files
       run: |
         GIT_LFS_SKIP_SMUDGE=1 git clone https://git.ligo.org/lscsoft/lalsuite-extra
diff --git a/.github/workflows/mac-test.yml b/.github/workflows/mac-test.yml
index 2a26882d7ae..8062a81fe6b 100644
--- a/.github/workflows/mac-test.yml
+++ b/.github/workflows/mac-test.yml
@@ -13,16 +13,46 @@ jobs:
       max-parallel: 4
       matrix:
         os: [macos-latest]
-        python-version: ['3.10', '3.11', '3.12']
+        python-version:
+          - '3.10'
+          - '3.11'
+          - '3.12'
+
+    # this is needed for conda environments to activate automatically
+    defaults:
+      run:
+        shell: bash -el {0}
+
     steps:
     - uses: actions/checkout@v1
-    - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v5
+
+    - name: Cache conda packages
+      uses: actions/cache@v4
+      env:
+        # increment to reset cache
+        CACHE_NUMBER: 0
+      with:
+        path: ~/conda_pkgs_dir
+        key: ${{ runner.os }}-conda-${{ matrix.python-version}}-${{ env.CACHE_NUMBER }}
+
+    - name: Configure conda
+      uses: conda-incubator/setup-miniconda@v3
       with:
+        activate-environment: test
+        channels: conda-forge
+        miniforge-version: latest
         python-version: ${{ matrix.python-version }}
-    - run: |
-        brew install fftw openssl gsl
-        pip install --upgrade pip setuptools "tox<4.0.0"
-    - name: run basic pycbc test suite
+
+    - name: Conda info
+      run: conda info --all
+
+    - name: Install tox
+      run: |
+        conda install \
+            pip \
+            setuptools \
+            tox
+
+    - name: Run basic pycbc test suite
       run: |
         tox -e py-unittest
diff --git a/test/validation_code/old_coinc.py b/test/validation_code/old_coinc.py
index 4d150d64a31..a8eb869f8a5 100644
--- a/test/validation_code/old_coinc.py
+++ b/test/validation_code/old_coinc.py
@@ -361,8 +361,8 @@ def cluster_coincs(stat, time1, time2, timeslide_id, slide, window, argmax=numpy
     else:
         time = 0.5 * (time2 + time1)
 
-    tslide = timeslide_id.astype(numpy.float128)
-    time = time.astype(numpy.float128)
+    tslide = timeslide_id.astype(numpy.longdouble)
+    time = time.astype(numpy.longdouble)
 
     span = (time.max() - time.min()) + window * 10
     time = time + span * tslide
@@ -411,8 +411,8 @@ def cluster_coincs_multiifo(stat, time_coincs, timeslide_id, slide, window, argm
         nifos_minusone = (num_ifos - numpy.ones_like(num_ifos))
         time_avg = time_avg + (nifos_minusone * timeslide_id * slide)/num_ifos
 
-    tslide = timeslide_id.astype(numpy.float128)
-    time_avg = time_avg.astype(numpy.float128)
+    tslide = timeslide_id.astype(numpy.longdouble)
+    time_avg = time_avg.astype(numpy.longdouble)
 
     span = (time_avg.max() - time_avg.min()) + window * 10
     time_avg = time_avg + span * tslide
diff --git a/tox.ini b/tox.ini
index d3d96b2039b..4c160e9c846 100644
--- a/tox.ini
+++ b/tox.ini
@@ -11,38 +11,45 @@ deps =
     :preinstall: -rrequirements.txt
     -rcompanion.txt
     mkl;'arm' not in platform_machine
+conda_deps =
+    c-compiler
+    cxx-compiler
+    gsl
+    mysqlclient
+    ; these packages don't install cleanly with pip, conda has patches
+    ligo-segments
+    python-ligo-lw
 
-[testenv]
-allowlist_externals = bash
-passenv=LAL_DATA_PATH
-conda_deps=openssl
-conda_channels=conda-forge
-platform = lin: linux
-           mac: darwin
-
-# This test should run on almost anybody's environment
-[testenv:py-unittest]
+[bbhx]
 deps =
-    {[base]deps}
-    pytest
-    ; Needed for `BBHx` package to work with PyCBC
     git+https://github.com/titodalcanton/BBHx.git@py39-and-cleanup; sys_platform == 'linux'
     git+https://github.com/gwastro/BBHX-waveform-model.git; sys_platform == 'linux'
-conda_deps=
-    mysqlclient
-    lin: gcc_linux-64>=12.2.0
-    lin: gxx_linux-64>=12.2.0
-    ; mac doesn't work, need fix
-    ; mac: clang_osx-64
-    ; mac: clangxx_osx-64
-    gsl
-    lapack==3.6.1
+conda_deps =
+    liblapacke
+    openblas
+
+[testenv]
+allowlist_externals =
+    bash
+    conda
 conda_channels=conda-forge
-setenv =
-    ; Tell the linker to look for shared libs inside the temporary Conda env.
-    ; Needed to build BBHx's wheel, whick links to LAPACK.
-    LIBRARY_PATH={envdir}/lib:{env:LIBRARY_PATH:}
+conda_deps =
+    {[base]conda_deps}
+    {[bbhx]conda_deps}
+commands_pre =
+    conda list
 commands = pytest
+deps =
+    {[base]deps}
+    {[bbhx]deps}
+    pytest
+passenv=LAL_DATA_PATH
+platform =
+    lin: linux
+    mac: darwin
+
+# This test should run on almost anybody's environment
+[testenv:py-unittest]
 
 # The following are long running or may require
 # some extra system-level dependencies or static files.
@@ -68,26 +75,6 @@ setenv = PYCBC_TEST_TYPE=inference
 commands = bash tools/pycbc_test_suite.sh
 
 [testenv:py-docs]
-deps =
-    {[base]deps}
-    ; Needed for `BBHx` package to work with PyCBC
-    git+https://github.com/titodalcanton/BBHx.git@py39-and-cleanup; sys_platform == 'linux'
-    git+https://github.com/gwastro/BBHX-waveform-model.git; sys_platform == 'linux'
-conda_deps=
-    mysqlclient
-    lin: gcc_linux-64>=12.2.0
-    lin: gxx_linux-64>=12.2.0
-    ; mac doesn't work, need fix
-    ; mac: clang_osx-64
-    ; mac: clangxx_osx-64
-    binutils_linux-64>=2.39
-    gsl
-    lapack==3.6.1
-    openmpi
-conda_channels=conda-forge
 setenv =
     PYCBC_TEST_TYPE=docs
-    ; Tell the linker to look for shared libs inside the temporary Conda env.
-    ; Needed to build BBHx's wheel, whick links to LAPACK.
-    LIBRARY_PATH={envdir}/lib:{env:LIBRARY_PATH:}
 commands = bash tools/pycbc_test_suite.sh