diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 5da60e13bd310..0eb68ef44511f 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -1,270 +1,23 @@
-# Copyright (c) 2023 The Bitcoin Core developers
-# Distributed under the MIT software license, see the accompanying
-# file COPYING or http://www.opensource.org/licenses/mit-license.php.
-
 name: CI
 on:
-  # See: https://docs.github.com/en/actions/using-workflows/events-that-trigger-workflows#pull_request.
   pull_request:
-  # See: https://docs.github.com/en/actions/using-workflows/events-that-trigger-workflows#push.
   push:
     branches:
       - '**'
     tags-ignore:
       - '**'
-
-concurrency:
-  group: ${{ github.event_name != 'pull_request' && github.run_id || github.ref }}
-  cancel-in-progress: true
-
-env:
-  CI_FAILFAST_TEST_LEAVE_DANGLING: 1  # GHA does not care about dangling processes and setting this variable avoids killing the CI script itself on error
-  MAKEJOBS: '-j10'
-
 jobs:
-  test-each-commit:
-    name: 'test each commit'
-    runs-on: ubuntu-24.04
-    if: github.event_name == 'pull_request' && github.event.pull_request.commits != 1
-    timeout-minutes: 360  # Use maximum time, see https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions#jobsjob_idtimeout-minutes. Assuming a worst case time of 1 hour per commit, this leads to a --max-count=6 below.
-    env:
-      MAX_COUNT: 6
+  build-and-test:
+    runs-on: [self-hosted, linux, x64]
+    timeout-minutes: 20
     steps:
-      - name: Determine fetch depth
-        run: echo "FETCH_DEPTH=$((${{ github.event.pull_request.commits }} + 2))" >> "$GITHUB_ENV"
-      - uses: actions/checkout@v4
-        with:
-          ref: ${{ github.event.pull_request.head.sha }}
-          fetch-depth: ${{ env.FETCH_DEPTH }}
-      - name: Determine commit range
-        run: |
-          # Checkout HEAD~ and find the test base commit
-          # Checkout HEAD~ because it would be wasteful to rerun tests on the PR
-          # head commit that are already run by other jobs.
-          git checkout HEAD~
-          # Figure out test base commit by listing ancestors of HEAD, excluding
-          # ancestors of the most recent merge commit, limiting the list to the
-          # newest MAX_COUNT ancestors, ordering it from oldest to newest, and
-          # taking the first one.
-          #
-          # If the branch contains up to MAX_COUNT ancestor commits after the
-          # most recent merge commit, all of those commits will be tested. If it
-          # contains more, only the most recent MAX_COUNT commits will be
-          # tested.
-          #
-          # In the command below, the ^@ suffix is used to refer to all parents
-          # of the merge commit as described in:
-          # https://git-scm.com/docs/git-rev-parse#_other_rev_parent_shorthand_notations
-          # and the ^ prefix is used to exclude these parents and all their
-          # ancestors from the rev-list output as described in:
-          # https://git-scm.com/docs/git-rev-list
-          MERGE_BASE=$(git rev-list -n1 --merges HEAD)
-          EXCLUDE_MERGE_BASE_ANCESTORS=
-          # MERGE_BASE can be empty due to limited fetch-depth
-          if test -n "$MERGE_BASE"; then
-            EXCLUDE_MERGE_BASE_ANCESTORS=^${MERGE_BASE}^@
-          fi
-          echo "TEST_BASE=$(git rev-list -n$((${{ env.MAX_COUNT }} + 1)) --reverse HEAD $EXCLUDE_MERGE_BASE_ANCESTORS | head -1)" >> "$GITHUB_ENV"
-      - run: |
-          sudo apt-get update
-          sudo apt-get install clang ccache build-essential cmake pkg-config python3-zmq libevent-dev libboost-dev libsqlite3-dev libdb++-dev systemtap-sdt-dev libzmq3-dev qtbase5-dev qttools5-dev qttools5-dev-tools qtwayland5 libqrencode-dev -y
-      - name: Compile and run tests
-        run: |
-          # Run tests on commits after the last merge commit and before the PR head commit
-          # Use clang++, because it is a bit faster and uses less memory than g++
-          git rebase --exec "echo Running test-one-commit on \$( git log -1 ) && CC=clang CXX=clang++ cmake -B build -DWERROR=ON -DWITH_ZMQ=ON -DBUILD_GUI=ON -DBUILD_BENCH=ON -DBUILD_FUZZ_BINARY=ON -DWITH_BDB=ON -DWITH_USDT=ON && cmake --build build -j $(nproc) && ctest --output-on-failure --test-dir build -j $(nproc) && ./build/test/functional/test_runner.py -j $(( $(nproc) * 2 ))" ${{ env.TEST_BASE }}
-
-  macos-native-arm64:
-    name: 'macOS 14 native, arm64, no depends, sqlite only, gui'
-    # Use latest image, but hardcode version to avoid silent upgrades (and breaks).
-    # See: https://github.com/actions/runner-images#available-images.
-    runs-on: macos-14
-
-    # No need to run on the read-only mirror, unless it is a PR.
-    if: github.repository != 'bitcoin-core/gui' || github.event_name == 'pull_request'
-
-    timeout-minutes: 120
-
-    env:
-      DANGER_RUN_CI_ON_HOST: 1
-      FILE_ENV: './ci/test/00_setup_env_mac_native.sh'
-      BASE_ROOT_DIR: ${{ github.workspace }}
-
-    steps:
-      - name: Checkout
-        uses: actions/checkout@v4
-
-      - name: Clang version
-        run: |
-          sudo xcode-select --switch /Applications/Xcode_15.0.app
-          clang --version
-
-      - name: Install Homebrew packages
-        env:
-          HOMEBREW_NO_INSTALLED_DEPENDENTS_CHECK: 1
-        run: |
-          # A workaround for "The `brew link` step did not complete successfully" error.
-          brew install --quiet python@3 || brew link --overwrite python@3
-          brew install --quiet coreutils ninja pkg-config gnu-getopt ccache boost libevent zeromq qt@5 qrencode
-
-      - name: Set Ccache directory
-        run: echo "CCACHE_DIR=${RUNNER_TEMP}/ccache_dir" >> "$GITHUB_ENV"
-
-      - name: Restore Ccache cache
-        id: ccache-cache
-        uses: actions/cache/restore@v4
-        with:
-          path: ${{ env.CCACHE_DIR }}
-          key: ${{ github.job }}-ccache-${{ github.run_id }}
-          restore-keys: ${{ github.job }}-ccache-
-
-      - name: CI script
-        run: ./ci/test_run_all.sh
-
-      - name: Save Ccache cache
-        uses: actions/cache/save@v4
-        if: github.event_name != 'pull_request' && steps.ccache-cache.outputs.cache-hit != 'true'
-        with:
-          path: ${{ env.CCACHE_DIR }}
-          # https://github.com/actions/cache/blob/main/tips-and-workarounds.md#update-a-cache
-          key: ${{ github.job }}-ccache-${{ github.run_id }}
-
-  win64-native:
-    name: 'Win64 native, VS 2022'
-    # Use latest image, but hardcode version to avoid silent upgrades (and breaks).
-    # See: https://github.com/actions/runner-images#available-images.
-    runs-on: windows-2022
-
-    # No need to run on the read-only mirror, unless it is a PR.
-    if: github.repository != 'bitcoin-core/gui' || github.event_name == 'pull_request'
-
-    env:
-      PYTHONUTF8: 1
-      TEST_RUNNER_TIMEOUT_FACTOR: 40
-
-    steps:
-      - name: Checkout
+      - name: Checkout repo
         uses: actions/checkout@v4
-
-      - name: Configure Developer Command Prompt for Microsoft Visual C++
-        # Using microsoft/setup-msbuild is not enough.
-        uses: ilammy/msvc-dev-cmd@v1
-        with:
-          arch: x64
-
-      - name: Get tool information
-        run: |
-          cmake -version | Tee-Object -FilePath "cmake_version"
-          Write-Output "---"
-          msbuild -version | Tee-Object -FilePath "msbuild_version"
-          $env:VCToolsVersion | Tee-Object -FilePath "toolset_version"
-          py -3 --version
-          Write-Host "PowerShell version $($PSVersionTable.PSVersion.ToString())"
-
-      - name: Using vcpkg with MSBuild
-        run: |
-          Set-Location "$env:VCPKG_INSTALLATION_ROOT"
-          Add-Content -Path "triplets\x64-windows.cmake" -Value "set(VCPKG_BUILD_TYPE release)"
-          Add-Content -Path "triplets\x64-windows-static.cmake" -Value "set(VCPKG_BUILD_TYPE release)"
-
-      - name: vcpkg tools cache
-        uses: actions/cache@v4
-        with:
-          path: C:/vcpkg/downloads/tools
-          key: ${{ github.job }}-vcpkg-tools
-
-      - name: Restore vcpkg binary cache
-        uses: actions/cache/restore@v4
-        id: vcpkg-binary-cache
+      - uses: cachix/install-nix-action@v27
         with:
-          path: ~/AppData/Local/vcpkg/archives
-          key: ${{ github.job }}-vcpkg-binary-${{ hashFiles('cmake_version', 'msbuild_version', 'toolset_version', 'vcpkg.json') }}
-
-      - name: Generate build system
-        run: |
-          cmake -B build --preset vs2022-static -DCMAKE_TOOLCHAIN_FILE="$env:VCPKG_INSTALLATION_ROOT\scripts\buildsystems\vcpkg.cmake" -DBUILD_GUI=ON -DWITH_BDB=ON -DWITH_ZMQ=ON -DBUILD_BENCH=ON -DBUILD_FUZZ_BINARY=ON -DWERROR=ON
-
-      - name: Save vcpkg binary cache
-        uses: actions/cache/save@v4
-        if: github.event_name != 'pull_request' && steps.vcpkg-binary-cache.outputs.cache-hit != 'true'
-        with:
-          path: ~/AppData/Local/vcpkg/archives
-          key: ${{ github.job }}-vcpkg-binary-${{ hashFiles('cmake_version', 'msbuild_version', 'toolset_version', 'vcpkg.json') }}
-
-      - name: Build
-        working-directory: build
-        run: |
-          cmake --build . -j $env:NUMBER_OF_PROCESSORS --config Release
-
-      - name: Run test suite
-        working-directory: build
-        run: |
-          ctest --output-on-failure -j $env:NUMBER_OF_PROCESSORS -C Release
-
-      - name: Run functional tests
-        working-directory: build
+          nix_path: nixpkgs=channel:nixos-unstable
+      - name: Build & test release
         env:
-          BITCOIND: '${{ github.workspace }}\build\src\Release\bitcoind.exe'
-          BITCOINCLI: '${{ github.workspace }}\build\src\Release\bitcoin-cli.exe'
-          BITCOINUTIL: '${{ github.workspace }}\build\src\Release\bitcoin-util.exe'
-          BITCOINWALLET: '${{ github.workspace }}\build\src\Release\bitcoin-wallet.exe'
-          TEST_RUNNER_EXTRA: ${{ github.event_name != 'pull_request' && '--extended' || '' }}
-        shell: cmd
-        run: py -3 test\functional\test_runner.py --jobs %NUMBER_OF_PROCESSORS% --ci --quiet --tmpdirprefix=%RUNNER_TEMP% --combinedlogslen=99999999 --timeout-factor=%TEST_RUNNER_TIMEOUT_FACTOR% %TEST_RUNNER_EXTRA%
-
-      - name: Clone fuzz corpus
+          NIX_PATH: nixpkgs=channel:nixos-unstable
         run: |
-          git clone --depth=1 https://github.com/bitcoin-core/qa-assets "$env:RUNNER_TEMP\qa-assets"
-          Set-Location "$env:RUNNER_TEMP\qa-assets"
-          Write-Host "Using qa-assets repo from commit ..."
-          git log -1
-
-      - name: Run fuzz binaries
-        working-directory: build
-        env:
-          BITCOINFUZZ: '${{ github.workspace }}\build\src\test\fuzz\Release\fuzz.exe'
-        shell: cmd
-        run: py -3 test\fuzz\test_runner.py --par %NUMBER_OF_PROCESSORS% --loglevel DEBUG %RUNNER_TEMP%\qa-assets\fuzz_corpora
-
-  asan-lsan-ubsan-integer-no-depends-usdt:
-    name: 'ASan + LSan + UBSan + integer, no depends, USDT'
-    runs-on: ubuntu-24.04 # has to match container in ci/test/00_setup_env_native_asan.sh for tracing tools
-    # No need to run on the read-only mirror, unless it is a PR.
-    if: github.repository != 'bitcoin-core/gui' || github.event_name == 'pull_request'
-    timeout-minutes: 120
-    env:
-      FILE_ENV: "./ci/test/00_setup_env_native_asan.sh"
-      DANGER_CI_ON_HOST_CACHE_FOLDERS: 1
-    steps:
-      - name: Checkout
-        uses: actions/checkout@v4
-
-      - name: Set Ccache directory
-        run: echo "CCACHE_DIR=${RUNNER_TEMP}/ccache_dir" >> "$GITHUB_ENV"
-
-      - name: Set base root directory
-        run: echo "BASE_ROOT_DIR=${RUNNER_TEMP}" >> "$GITHUB_ENV"
-
-      - name: Restore Ccache cache
-        id: ccache-cache
-        uses: actions/cache/restore@v4
-        with:
-          path: ${{ env.CCACHE_DIR }}
-          key: ${{ github.job }}-ccache-${{ github.run_id }}
-          restore-keys: ${{ github.job }}-ccache-
-
-      - name: Enable bpfcc script
-        # In the image build step, no external environment variables are available,
-        # so any settings will need to be written to the settings env file:
-        run: sed -i "s|\${INSTALL_BCC_TRACING_TOOLS}|true|g" ./ci/test/00_setup_env_native_asan.sh
-
-      - name: CI script
-        run: ./ci/test_run_all.sh
-
-      - name: Save Ccache cache
-        uses: actions/cache/save@v4
-        if: github.event_name != 'pull_request' && steps.ccache-cache.outputs.cache-hit != 'true'
-        with:
-          path: ${{ env.CCACHE_DIR }}
-          # https://github.com/actions/cache/blob/main/tips-and-workarounds.md#update-a-cache
-          key: ${{ github.job }}-ccache-${{ github.run_id }}
+          nix-shell --command "just run-ci"
diff --git a/justfile b/justfile
new file mode 100644
index 0000000000000..0feef8a422371
--- /dev/null
+++ b/justfile
@@ -0,0 +1,67 @@
+set shell := ["bash", "-uc"]
+
+os := os()
+
+default:
+    just --list
+
+# Build default project
+[group('build')]
+build *args: clean
+    cmake -B build {{ args }}
+    cmake --build build -j {{ num_cpus() }}
+
+# Build with all optional modules
+[group('build')]
+build-dev *args: clean
+    cmake -B build --preset dev-mode {{ args }}
+    cmake --build build -j {{ num_cpus() }}
+
+# Build for the CI, including bench_bitcoin
+[private]
+[group('ci')]
+build-ci: clean
+    cmake -B build -DBUILD_BENCH=ON
+    cmake --build build -j {{ num_cpus() }}
+# Re-build current config
+[group('build')]
+rebuild:
+    cmake --build build -j {{ num_cpus() }}
+
+# Clean build dir using git clean -dfx
+[group('build')]
+clean:
+    git clean -dfx
+
+# Run unit tests
+[group('test')]
+test-unit:
+    ctest --test-dir build -j {{ num_cpus() }}
+
+# Run all functional tests
+[group('test')]
+test-func:
+    build/test/functional/test_runner.py -j {{ num_cpus() }}
+
+# Run all unit and functional tests
+[group('test')]
+test: test-unit test-func
+
+# Run a single functional test (filename.py)
+[group('test')]
+test-func1 test:
+    build/test/functional/test_runner.py {{ test }}
+
+# Run a single unit test suite
+[group('test')]
+test-unit1 suite:
+    build/src/test/test_bitcoin --log_level=all --run_test={{ suite }}
+
+# Run benchmarks
+[group('perf')]
+bench:
+    build/src/bench/bench_bitcoin
+
+# Run the CI workflow
+[group('ci')]
+run-ci: build-ci bench test
diff --git a/shell.nix b/shell.nix
new file mode 100644
index 0000000000000..6cf45818c220a
--- /dev/null
+++ b/shell.nix
@@ -0,0 +1,125 @@
+# Copyright 0xB10C
+
+{ pkgs ? import (fetchTarball "https://github.com/nixos/nixpkgs/archive/nixos-unstable.tar.gz") {},
+  bdbVersion ? "",
+  spareCores ? 0,
+  withClang ? false,
+  withDebug ? false,
+  withGui ? false,
+}:
+let
+  inherit (pkgs.lib) optionals strings;
+  binDirs =
+    [ "\$PWD/src" ]
+    ++ optionals withGui [ "\$PWD/src/qt" ];
+  configureFlags =
+    [ "--with-boost-libdir=$NIX_BOOST_LIB_DIR" ]
+    ++ optionals ((builtins.elem bdbVersion ["" "db48" "db5"]) || abort "Unsupported bdbVersion value: ${bdbVersion}") []
+    ++ optionals (bdbVersion == "") [ "--without-bdb" ]
+    ++ optionals (!(builtins.elem bdbVersion ["" "db48"])) [ "--with-incompatible-bdb" ]
+    ++ optionals withClang [ "CXX=clang++" "CC=clang" ]
+    ++ optionals withDebug [ "--enable-debug" ]
+    ++ optionals withGui [
+      "--with-gui=qt5"
+      "--with-qt-bindir=${pkgs.qt5.qtbase.dev}/bin:${pkgs.qt5.qttools.dev}/bin"
+    ];
+  jobs =
+    if (strings.hasSuffix "linux" builtins.currentSystem) then "$(($(nproc)-${toString spareCores}))"
+    else if (strings.hasSuffix "darwin" builtins.currentSystem) then "$(($(sysctl -n hw.physicalcpu)-${toString spareCores}))"
+    else "6";
+in pkgs.mkShell {
+    nativeBuildInputs = with pkgs; [
+      autoconf
+      automake
+      libtool
+      pkg-config
+      boost
+      libevent
+      zeromq
+      sqlite
+      clang_18
+
+      # tests
+      hexdump
+
+      # compiler output caching per
+      # https://github.com/bitcoin/bitcoin/blob/master/doc/productivity.md#cache-compilations-with-ccache
+      ccache
+
+      # generating compile_commands.json for clang-format, clang-tidy, LSPs etc
+      # https://github.com/bitcoin/bitcoin/blob/master/doc/developer-notes.md#running-clang-tidy
+      # $ a && c && m clean && bear --config src/.bear-tidy-config -- make -j6
+      clang-tools_18
+      bear
+
+      # for newer cmake building
+      cmake
+
+      # depends
+      byacc
+
+      # functional tests & linting
+      python3
+      python3Packages.flake8
+      python3Packages.lief
+      python3Packages.autopep8
+      python3Packages.mypy
+      python3Packages.requests
+      python3Packages.pyzmq
+
+      # benchmarking
+      python3Packages.pyperf
+
+      # debugging
+      gdb
+
+      # tracing
+      libsystemtap
+      linuxPackages.bpftrace
+      linuxPackages.bcc
+
+    ]
+    ++ lib.optionals (bdbVersion == "db48") [
+      db48
+    ]
+    ++ lib.optionals (bdbVersion == "db5") [
+      db5
+    ]
+    ++ lib.optionals withGui [
+      # bitcoin-qt
+      qt5.qtbase
+      # required for bitcoin-qt for "LRELEASE" etc
+      qt5.qttools
+    ];
+    buildInputs = with pkgs; [
+      just
+      bash
+    ];
+
+
+
+    # Modifies the Nix clang++ wrapper to avoid warning:
+    # "_FORTIFY_SOURCE requires compiling with optimization (-O)"
+    hardeningDisable = if withDebug then [ "all" ] else [ ];
+
+    # Fixes xcb plugin error when trying to launch bitcoin-qt
+    QT_QPA_PLATFORM_PLUGIN_PATH = if withGui then "${pkgs.qt5.qtbase.bin}/lib/qt-${pkgs.qt5.qtbase.version}/plugins/platforms" else "";
+
+    shellHook = ''
+      echo "Bitcoin Core build nix-shell"
+      echo ""
+
+      BCC_EGG=${pkgs.linuxPackages.bcc}/${pkgs.python3.sitePackages}/bcc-${pkgs.linuxPackages.bcc.version}-py3.${pkgs.python3.sourceVersion.minor}.egg
+
+      echo "adding bcc egg to PYTHONPATH: $BCC_EGG"
+      if [ -f $BCC_EGG ]; then
+        export PYTHONPATH="$PYTHONPATH:$BCC_EGG"
+        echo ""
+      else
+        echo "The bcc egg $BCC_EGG does not exist. Maybe the python or bcc version is different?"
+      fi
+
+      echo "adding ${builtins.concatStringsSep ":" binDirs} to \$PATH to make running built binaries more natural"
+      export PATH=$PATH:${builtins.concatStringsSep ":" binDirs};
+    '';
+}