diff --git a/.github/workflows/bash.yml b/.github/workflows/bash.yml
deleted file mode 100644
index eb34e3ad76d..00000000000
--- a/.github/workflows/bash.yml
+++ /dev/null
@@ -1,91 +0,0 @@
-# Workflow for testing multiple bash versions with Docker
-name: bash
-
-on:
-  workflow_dispatch:
-  pull_request:
-    paths-ignore:
-      - '.github/workflows/*.ya?ml'
-      - '!.github/workflows/bash.yml'
-      - 'cylc/flow/etc/syntax/**'
-      - 'etc/syntax/**'
-      - 'tests/unit/**'
-      - 'tests/integration/**'
-      - '**.md'
-      - '**/README*/**'
-  push:
-    branches:
-      - master
-      - '8.*.x'
-    paths-ignore:
-      - '.github/workflows/*.ya?ml'
-      - '!.github/workflows/bash.yml'
-      - 'cylc/flow/etc/syntax/**'
-      - 'etc/syntax/**'
-      - 'tests/unit/**'
-      - 'tests/integration/**'
-      - '**.md'
-      - '**/README*/**'
-
-concurrency:
-  group: ${{ github.workflow }}-${{ github.ref }}
-  cancel-in-progress: true
-
-jobs:
-  bash-docker:
-    runs-on: ubuntu-latest
-    timeout-minutes: 15
-    strategy:
-      matrix:
-        bash-version:
-          - '3.2'
-          - '4.2'
-          # if you use a value like 5.0, YAML will round it to 5, which will cause an error later on
-          - '5.0'
-    steps:
-      - name: Checkout
-        uses: actions/checkout@v4
-
-      - name: Run Docker container
-        run: |
-          docker pull ghcr.io/cylc/cylc-bash-testing:master
-          docker run --name bash -v $(pwd -P):/root/cylc-flow --rm -t -d -m 1G --memory-swap 1G ghcr.io/cylc/cylc-bash-testing:master /bin/bash
-          docker ps -a
-
-      - name: Install Cylc dependencies in the container
-        run: |
-          docker exec bash python3.7 -m pip install six==1.12
-          docker exec -w /root/cylc-flow bash python3.7 -m pip install .[all]
-
-      - name: Set the container bash version
-        run: docker exec bash update-alternatives --set bash /bash/bash-${{ matrix.bash-version }}
-
-      - name: Run functional tests that validate or are related to how Cylc uses bash
-        run: |
-          docker exec -w /root/cylc-flow bash \
-            ./etc/bin/run-functional-tests -v \
-            tests/functional/broadcast/00-simple.t \
-            tests/functional/cylc-poll/11-event-time.t \
-            tests/functional/cylc-poll/15-job-st-file-no-batch.t \
-            tests/functional/events/28-inactivity.t \
-            tests/functional/events/34-task-abort.t \
-            tests/functional/job-file-trap/00-sigusr1.t \
-            tests/functional/job-file-trap/02-pipefail.t \
-            tests/functional/job-file-trap/03-user-trap.t \
-            tests/functional/jobscript/00-torture.t \
-            tests/functional/pause-resume/12-pause-then-retry.t \
-            tests/functional/shutdown/09-now2.t \
-            tests/functional/shutdown/13-no-port-file-check.t \
-            tests/functional/shutdown/14-no-dir-check.t
-
-      - name: Copy cylc-run out of container
-        if: failure()
-        run: |
-          docker cp bash:/root/cylc-run .
-
-      - name: Upload artifact
-        if: failure()
-        uses: actions/upload-artifact@v4
-        with:
-          name: 'cylc-run (bash-${{ matrix.bash-version }})'
-          path: cylc-run
diff --git a/.github/workflows/test_fast.yml b/.github/workflows/test_fast.yml
deleted file mode 100644
index 5776185557e..00000000000
--- a/.github/workflows/test_fast.yml
+++ /dev/null
@@ -1,151 +0,0 @@
-name: fast tests
-
-on:
-  pull_request:
-  workflow_dispatch:
-  push:
-    branches:
-      - master
-      - '8.*.x'
-
-concurrency:
-  group: ${{ github.workflow }}-${{ github.ref }}
-  cancel-in-progress: true
-
-jobs:
-  test:
-    runs-on: ${{ matrix.os }}
-    timeout-minutes: 20
-    strategy:
-      fail-fast: false # don't stop on first failure
-      matrix:
-        os: ['ubuntu-latest']
-        python-version: ['3.7', '3.8', '3.10', '3.11', '3']
-        include:
-          # mac os test
-          - os: 'macos-11'
-            python-version: '3.7'  # oldest supported version
-
-          # non-utc timezone test
-          - os: 'ubuntu-latest'
-            python-version: '3.9'  # not the oldest, not the most recent version
-            time-zone: 'XXX-09:35'
-
-    env:
-      TZ: ${{ matrix.time-zone }}
-      PYTEST_ADDOPTS: --cov --cov-append -n 5 --color=yes
-
-    steps:
-      - name: Checkout
-        uses: actions/checkout@v4
-
-      - name: Configure Python
-        uses: actions/setup-python@v5
-        with:
-          python-version: ${{ matrix.python-version }}
-
-      - name: Apt-Get Install
-        if: startsWith(matrix.os, 'ubuntu')
-        run: |
-          sudo apt-get update
-          sudo apt-get install -y sqlite3
-
-      - name: Install
-        run: |
-          pip install -e ."[all]"
-
-      - name: Configure git  # Needed by the odd test
-        uses: cylc/release-actions/configure-git@v1
-
-      - name: Unit Tests
-        timeout-minutes: 5
-        run: |
-          pytest cylc/flow tests/unit
-
-      - name: Integration Tests
-        timeout-minutes: 6
-        run: |
-          pytest tests/integration
-
-      - name: Upload failed tests artifact
-        if: failure()
-        uses: actions/upload-artifact@v4
-        with:
-          name: cylc-run (${{ matrix.os }} py-${{ matrix.python-version }})
-          path: ~/cylc-run/
-
-      - name: Coverage report
-        run: |
-          coverage xml
-          coverage report
-
-      - name: Upload coverage artifact
-        uses: actions/upload-artifact@v4
-        with:
-          name: coverage_${{ matrix.os }}_py-${{ matrix.python-version }}
-          path: coverage.xml
-          retention-days: 7
-
-  lint:
-    runs-on: 'ubuntu-latest'
-    timeout-minutes: 10
-    steps:
-      - name: Apt-Get Install
-        run: |
-          sudo apt-get update
-          sudo apt-get install -y shellcheck
-
-      - name: Checkout
-        uses: actions/checkout@v4
-
-      # note: exclude python 3.10+ from mypy checks as these produce false
-      # positives in installed libraries for python 3.7
-      - name: Configure Python
-        uses: actions/setup-python@v5
-        with:
-          python-version: 3.9
-
-      - name: Install
-        run: |
-          pip install -e ."[tests]"
-
-      - name: Flake8
-        run: flake8
-
-      - name: Bandit
-        run: |
-          bandit -r --ini .bandit cylc/flow
-
-      - name: Shellchecker
-        run: etc/bin/shellchecker
-
-      - name: MyPy
-        run: mypy
-
-      - name: Towncrier
-        run: towncrier build --draft
-
-      - name: Linkcheck
-        run: pytest -m linkcheck --dist=load --color=yes -n 10 tests/unit/test_links.py
-
-  codecov:
-    needs: test
-    runs-on: ubuntu-latest
-    timeout-minutes: 2
-    steps:
-      - name: Checkout
-        uses: actions/checkout@v4
-
-      - name: Download coverage artifacts
-        uses: actions/download-artifact@v4
-
-      - name: Codecov upload
-        uses: codecov/codecov-action@v4
-        with:
-          name: ${{ github.workflow }}
-          flags: fast-tests
-          fail_ci_if_error: true
-          verbose: true
-          # Token not required for public repos, but avoids upload failure due
-          # to rate-limiting (but not for PRs opened from forks)
-          token: ${{ secrets.CODECOV_TOKEN }}
diff --git a/.github/workflows/test_functional.yml b/.github/workflows/test_functional.yml
index f54f3b3d710..c83bbe9db7f 100644
--- a/.github/workflows/test_functional.yml
+++ b/.github/workflows/test_functional.yml
@@ -33,7 +33,7 @@ concurrency:
 jobs:
   test:
     runs-on: ${{ matrix.os }}
-    name: ${{ matrix.name || matrix.chunk }}
+    name: ${{ matrix.name }}
     timeout-minutes: 45
     strategy:
       fail-fast: false
@@ -41,58 +41,12 @@ jobs:
         os: ['ubuntu-latest']
         python-version: ['3.7']
         test-base: ['tests/f']
-        chunk: ['1/4', '2/4', '3/4', '4/4']
-        platform: ['_local_background* _local_at*']
-        # NOTE: includes must define ALL of the matrix values
-        include:
-          # latest python
-          - name: 'py-3-latest'
-            os: 'ubuntu-latest'
-            python-version: '3'
-            test-base: 'tests/f'
-            chunk: '1/4'
-            platform: '_local_background*'
-          # tests/k
-          - name: 'flaky'
-            os: 'ubuntu-latest'
-            python-version: '3.7'
-            test-base: 'tests/k'
-            chunk: '1/1'
-            platform: '_local_background* _local_at*'
-          # remote platforms
-          - name: '_remote_background_indep_poll'
-            os: 'ubuntu-latest'
-            python-version: '3.7'
-            test-base: 'tests/f tests/k'
-            chunk: '1/1'
-            platform: '_remote_background_indep_poll _remote_at_indep_poll'
-          - name: '_remote_background_indep_tcp'
-            os: 'ubuntu-latest'
-            test-base: 'tests/f tests/k'
-            python-version: '3.7'
-            chunk: '1/1'
-            platform: '_remote_background_indep_tcp _remote_at_indep_tcp'
-          # macos
-          - name: 'macos 1/5'
-            os: 'macos-11'
-            python-version: '3.7'
-            test-base: 'tests/f'
-            chunk: '1/5'
-            platform: '_local_background*'
-          - name: 'macos 2/5'
-            os: 'macos-11'
-            python-version: '3.7'
-            test-base: 'tests/f'
-            chunk: '2/5'
-            platform: '_local_background*'
 
     env:
       # Use non-UTC time zone
       TZ: XXX-05:30
       # these vars are used by etc/bin/run-functional-tests
-      CYLC_TEST_PLATFORMS: ${{ matrix.platform }}
       CYLC_COVERAGE: 1
-      REMOTE_PLATFORM: ${{ contains(matrix.platform, '_remote') }}
 
     steps:
       - name: Checkout
@@ -144,12 +98,15 @@ jobs:
           mkdir "$HOME/cylc-run"
 
       - name: Configure Atrun
-        if: contains(matrix.platform, '_local_at')
         run: |
           PTH="$HOME/.cylc/flow/"
           mkdir -p "${PTH}"
           cat > "${PTH}/global.cylc" << __HERE__
             [platforms]
+                [[_local_background_indep_tcp]]
+                    hosts = localhost
+                    install target = localhost
+                    job runner = background
                 [[_local_at_indep_tcp]]
                     hosts = localhost
                     install target = localhost
@@ -157,87 +114,16 @@ jobs:
           __HERE__
           cp "${PTH}/global.cylc" "${PTH}/global-tests.cylc"
 
-      - name: Swarm Configure
-        run: |
-          etc/bin/swarm --yes --debug configure
-
-      - name: Swarm Build
-        if: env.REMOTE_PLATFORM == 'true'
-        run: |
-          # `swarm configure` seems to get ignored so override the user config
-          cp etc/conf/ssh_config $HOME/.ssh/config
-          # build and run the swarm
-          etc/bin/swarm --yes --debug build
-          etc/bin/swarm --yes --debug run
-          # test that it's up and running before proceeding
-          sleep 1
-          ssh -vv _remote_background_indep_poll hostname
-
-      - name: Configure git  # Needed by the odd test
-        uses: cylc/release-actions/configure-git@v1
-
-      - name: Filter Tests
-        env:
-          # NOTE: we only want the CHUNK set in this step else we will
-          # re-chunk tests later when they run
-          CHUNK: ${{ matrix.chunk }}
-        run: |
-          etc/bin/run-functional-tests \
-            --dry \
-            ${{ matrix.test-base }} \
-            > test-file
-          if [[ $REMOTE_PLATFORM == 'true' ]]; then
-            # skip tests that don't configure platform requirements
-            grep -l --color=never REQUIRE_PLATFORM $(cat test-file) > test-file
-          fi
-
       - name: Test
         id: test
-        timeout-minutes: 35
-        continue-on-error: true
+        timeout-minutes: 15
         run: |
-          echo "finished=false" >> $GITHUB_OUTPUT
-          if [[ '${{ matrix.test-base }}' == 'tests/k' ]]; then
-              NPROC=4
-          else
-              NPROC=8
-          fi
-          # NOTE: test base is purposefully un-quoted
           etc/bin/run-functional-tests \
-              -j "${NPROC}" \
-              --state=save \
-              $(cat test-file) \
-              || (echo "finished=true" >> $GITHUB_OUTPUT && false)
-
-      - name: Time Out
-        if: steps.test.outcome == 'failure' && steps.test.outputs.finished != 'true'
-        run: |
-          echo '::error:: tests timed-out'
-          # help to identify the tests that were running at the time
-          cylc scan --state=all --format=rich --color-blind
-          # fail the workflow
-          false
-
-      - name: Re-run failed tests
-        timeout-minutes: 10
-        if: steps.test.outcome == 'failure' && steps.test.outputs.finished == 'true'
-        run: |
-          # re-run failed tests providing that they didn't time out first time
-          # TODO: make the tests deterministic so we don't need to do this
-          etc/bin/run-functional-tests \
-              -j 1 \
               -v \
-              --state=save,failed $(cat test-file)
-
-      - name: Copy cylc-run out of container
-        if: failure() && steps.test.outcome == 'failure' && env.REMOTE_PLATFORM == 'true'
-        run: |
-          # pick the first host in the list
-          host="$(cut -d ' ' -f 1 <<< "${{ matrix.platform }}")"
-          # copy back the remote cylc-run dir
-          rsync -av \
-            "${host}:/root/cylc-run/" \
-            "${HOME}/cylc-run/${host}/"
+              -j 1 \
+              -p _local_background_indep_tcp \
+              tests/f/spawn-on-demand/19-submitted-compat.t \
+              tests/f/optional-outputs/01-stall-on-incomplete.t
 
       - name: Debug
         if: failure() && steps.test.outcome == 'failure'
@@ -255,7 +141,7 @@ jobs:
         id: uploadname
         run: |
           # artifact name cannot contain '/' characters
-          CID="$(sed 's|/|-|g' <<< "${{ matrix.name || matrix.chunk }}")"
+          CID="$(sed 's|/|-|g' <<< "${{ matrix.name }}")"
           echo "uploadname=$CID" >> $GITHUB_OUTPUT
 
       - name: Upload failed tests artifact
@@ -265,27 +151,6 @@ jobs:
           name: cylc-run (${{ steps.uploadname.outputs.uploadname }})
           path: ~/cylc-run/
 
-      - name: Fetch Remote Coverage
-        if: env.REMOTE_PLATFORM == 'true'
-        run: |
-          # pick the first host in the list
-          host="$(cut -d ' ' -f 1 <<< "${{ matrix.platform }}")"
-          # copy back the remote coverage files
-          rsync -av \
-            "${host}:/cylc/" \
-            '.' \
-            --include='.coverage*' \
-            --exclude='*' \
-            >rsyncout
-          cat rsyncout
-          # fiddle the python source location to match the local system
-          for db in $(grep --color=never '.coverage\.' rsyncout); do
-            sqlite3 "$db" "
-              UPDATE file
-              SET path = REPLACE(path, '/cylc/cylc/', '$PWD/cylc/')
-            "
-          done
-
       - name: Shutdown
         if: always()
         run: |
diff --git a/.github/workflows/test_tutorial_workflow.yml b/.github/workflows/test_tutorial_workflow.yml
deleted file mode 100644
index 7859b8588e2..00000000000
--- a/.github/workflows/test_tutorial_workflow.yml
+++ /dev/null
@@ -1,51 +0,0 @@
-name: test-tutorial-workflow
-
-on:
-  push:
-    branches:
-      - master
-      - '8.*.x'
-  pull_request:
-    paths-ignore:
-      - '.github/workflows/*.ya?ml'
-      - '!.github/workflows/test_tutorial_workflow.yml'
-      - 'tests/**'
-      - '**.md'
-  workflow_dispatch:
-
-concurrency:
-  group: ${{ github.workflow }}-${{ github.ref }}
-  cancel-in-progress: true
-
-jobs:
-  test:
-    strategy:
-      matrix:
-        python-version: ['3.7', '3']
-    runs-on: ubuntu-latest
-    timeout-minutes: 10
-    steps:
-      - name: configure python
-        uses: actions/setup-python@v5
-        with:
-          python-version: ${{ matrix.python-version }}
-
-      - name: checkout
-        uses: actions/checkout@v4
-
-      - name: Install docs/tutorial dependencies
-        uses: cylc/cylc-doc/.github/actions/install-dependencies@master
-
-      - name: install cylc-flow
-        run: pip install .[all]
-
-      - name: run tutorial workflow
-        timeout-minutes: 6
-        run: |
-          mkdir -p "${HOME}/cylc-run"
-          etc/bin/run-validate-tutorials
-
-      - name: debug
-        if: failure()
-        run: |
-          find ~/cylc-run -name job.err -exec cat {} +  # cylc error files