diff --git a/.gitattributes b/.gitattributes
index 06d51d28a9..b7e204ab21 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -18,3 +18,4 @@
 #     file gets renamed again ...
 
 ChangeLog       merge=merge-changelog
+*.sh eol=lf
diff --git a/.github/workflows/build.yaml b/.github/workflows/build.yaml
index 4e219c3cea..eb6372c15b 100644
--- a/.github/workflows/build.yaml
+++ b/.github/workflows/build.yaml
@@ -38,6 +38,22 @@ jobs:
           name: install
           path: _dest/
 
+      - name: Build test programs
+        shell: msys2 {0}
+        run: |
+          make -C x86_64-pc-cygwin/winsup/testsuite -j8 \
+            CFLAGS="-O2 -pipe -ggdb -std=gnu89 -w" check_programs
+
+      - name: Bundle up worktree
+        shell: msys2 {0}
+        run: $WINDIR/system32/tar.exe -czf wt.tgz --exclude _dest --exclude .git --exclude wt.tgz .
+
+      - name: Upload worktree archive
+        uses: actions/upload-artifact@v7
+        with:
+          name: wt.tgz
+          path: wt.tgz
+
   generate-msys2-tests-matrix:
     runs-on: ubuntu-latest
     outputs:
@@ -93,3 +109,50 @@ jobs:
       - name: Run tests
         uses: msys2/msys2-tests@main
 
+  cygwin-tests:
+    needs: [build]
+    runs-on: windows-latest
+    steps:
+      - name: setup-msys2
+        uses: msys2/setup-msys2@v2
+        with:
+          msystem: MSYS
+          update: true
+          install: msys2-devel base-devel diffutils make perl busybox cygutils
+
+      - name: Download worktree archive
+        uses: actions/download-artifact@v7
+        with:
+          name: wt.tgz
+
+      - name: Extract worktree
+        shell: msys2 {0}
+        run: $WINDIR/system32/tar.exe -xzf wt.tgz
+
+      - name: Run the test suite of Cygwin
+        shell: msys2 {0}
+        run: |
+          export PATH=/usr/bin:$WINDIR/system32
+          export MAKEFLAGS=-j8
+          export MSYS=winsymlinks:nativestrict
+          WINSUP=$PWD/x86_64-pc-cygwin/winsup
+          cp $WINSUP/cygserver/cygserver.exe $WINSUP/testsuite/testinst/usr/bin/
+          ( cd $WINSUP/testsuite/testinst/usr/bin && PATH=$PWD:$WINDIR/system32 "$WINDIR/System32/WindowsPowerShell/v1.0/powershell.exe" -command '& .\cygserver.exe' & )
+          # cygserver is launched asynchronously; wait for it to come up before
+          # running the SysV IPC tests (semtest/shmtest/msgtest) that depend on
+          # it, otherwise they race its startup and fail intermittently.
+          for i in $(seq 1 60); do
+            "$WINDIR/System32/tasklist.exe" //FI "IMAGENAME eq cygserver.exe" 2>/dev/null | grep -qi cygserver && break
+            sleep 1
+          done
+          sleep 5
+          cd $WINSUP && make check AM_COLOR_TESTS=always
+
+      - name: Upload testsuite logs
+        if: always()
+        uses: actions/upload-artifact@v7
+        with:
+          name: cygwin-testsuite-logs
+          path: |
+            x86_64-pc-cygwin/winsup/testsuite/**/*.log
+            x86_64-pc-cygwin/winsup/testsuite/**/*.trs
diff --git a/.github/workflows/cygwin.yml b/.github/workflows/cygwin.yml
deleted file mode 100644
index 998dc01576..0000000000
--- a/.github/workflows/cygwin.yml
+++ /dev/null
@@ -1,181 +0,0 @@
-name: cygwin
-
-on: workflow_dispatch
-
-jobs:
-  fedora-build:
-    runs-on: ubuntu-latest
-    container: fedora:latest
-    strategy:
-      fail-fast: false
-      matrix:
-        include:
-        - target: x86_64-pc-cygwin
-          pkgarch: 64
-    name: Fedora cross ${{ matrix.target }}
-
-    env:
-      HAS_SSH_KEY: ${{ secrets.SSH_KEY != '' }}
-
-    steps:
-    - uses: actions/checkout@v3
-
-    # install build tools
-    - name: Install build tools
-      run: |
-        dnf install -y autoconf automake gawk make patch perl mingw${{ matrix.pkgarch }}-gcc-c++ mingw${{ matrix.pkgarch }}-winpthreads-static mingw${{ matrix.pkgarch }}-zlib-static
-
-    # enable 'dnf copr'
-    - name: Enable 'dnf copr'
-      run: |
-        dnf install -y dnf-plugins-core
-
-    # install cross-cygwin toolchain and libs from copr
-    - name: Install cross-cygwin toolchain and libs and cocom from copr
-      run: |
-        dnf copr enable -y yselkowitz/cygwin
-        dnf install -y cygwin${{ matrix.pkgarch }}-gcc-c++ cygwin${{ matrix.pkgarch }}-gettext cygwin${{ matrix.pkgarch }}-libbfd cygwin${{ matrix.pkgarch }}-libiconv cygwin${{ matrix.pkgarch }}-zlib cocom
-
-    # install doc tools
-    - name: Install doc tools
-      run: |
-        dnf install -y dblatex docbook2X docbook-xsl xmlto python3 python3-lxml python3-ply openssh-clients
-        fmtutil-sys --byfmt pdflatex && texhash
-
-    # build
-    - name: Configure, build and install
-      run: |
-        mkdir build install
-        (cd winsup && ./autogen.sh)
-        (cd build && ../configure --target=${{ matrix.target }} --prefix=$(realpath $(pwd)/../install) )
-        make -C build
-        make -C build/*/newlib info man
-        make -C build install
-        make -C build/*/newlib install-info install-man
-
-    # deploy documentation
-    - name: Deploy documentation
-      env:
-        SSH_AUTH_SOCK: /tmp/ssh_agent.sock
-      run: |
-        # pushes to main are deployed as preview
-        # pushes to cygwin-n.n.n (but not 'cygwin-n.n.n.dev') tags are deployed as stable
-        # other references are ignored by this step
-        case "${{ github.ref }}" in
-          refs/heads/main)
-            DEST='preview'
-            ;;
-          refs/tags/cygwin-[0-9.]*)
-            DEST='stable'
-            ;;
-          *)
-            exit 0
-            ;;
-        esac
-        # unfuck github fuckery of HOME in a container
-        unset HOME
-        # add the hosts public key to known_hosts
-        mkdir -p ~/.ssh/
-        echo "cygwin.com ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIKoejTnTCbXaIIMYfbX7t4tYUOQ2bTxZC3e/td3BageF" >> ~/.ssh/known_hosts
-        # load the key (restricted to scp only) into ssh-agent
-        ssh-agent -a $SSH_AUTH_SOCK > /dev/null
-        ssh-add - <<< "${{ secrets.SSH_KEY }}"
-        # 'make install' doesn't install faq, so instead just deploy from build directory
-        scp -pr build/*/winsup/doc/{cygwin-api,cygwin-ug-net,faq} cygwin-admin@cygwin.com:/sourceware/www/sourceware/htdocs/cygwin/doc/${DEST}/
-      if: env.HAS_SSH_KEY == 'true'
-
-  windows-build:
-    runs-on: windows-latest
-    strategy:
-      fail-fast: false
-      matrix:
-        include:
-        - target: x86_64-pc-cygwin
-          pkgarch: x86_64
-    name: Windows native ${{ matrix.pkgarch }}
-
-    steps:
-    # checkout action uses the native git (we can avoid this messing up line
-    # endings, but this could still be dangerous e.g if we need symlinks in the
-    # repo)
-    - run: git config --global core.autocrlf input
-    # remove inheritable permissions since they break assumptions testsuite
-    # makes about file modes
-    - name: adjust permissions
-      run: |
-        icacls . /inheritance:r
-        icacls . /grant Administrators:F
-    - uses: actions/checkout@v3
-
-    # install cygwin and build tools
-    - name: Install Cygwin
-      uses: cygwin/cygwin-install-action@master
-      with:
-        platform: ${{ matrix.pkgarch }}
-        packages: >-
-          autoconf,
-          automake,
-          busybox,
-          cocom,
-          cygutils-extra,
-          dblatex,
-          dejagnu,
-          docbook-xml45,
-          docbook-xsl,
-          docbook2X,
-          gcc-g++,
-          gettext-devel,
-          libiconv,
-          libiconv-devel,
-          libzstd-devel,
-          make,
-          mingw64-${{ matrix.pkgarch }}-gcc-g++,
-          mingw64-${{ matrix.pkgarch }}-zlib,
-          patch,
-          perl,
-          python39-lxml,
-          python39-ply,
-          texlive-collection-fontsrecommended,
-          texlive-collection-latexrecommended,
-          texlive-collection-pictures,
-          xmlto,
-          zlib-devel
-
-    # build
-    - name: Build Cygwin
-      run: >-
-        export PATH=/usr/bin:$(cygpath ${SYSTEMROOT})/system32 &&
-        mkdir build install &&
-        (cd winsup; ./autogen.sh) &&
-        cd build &&
-        ../configure --prefix=$(realpath $(pwd)/../install) -v &&
-        export MAKEFLAGS=-j$(nproc) &&
-        make &&
-        make install &&
-        (cd */newlib; make info man) &&
-        (cd */newlib; make install-info install-man)
-      shell: C:\cygwin\bin\bash.exe --noprofile --norc -eo pipefail '{0}'
-
-    # test
-    - name: Test Cygwin
-      run: >-
-        export PATH=/usr/bin:$(cygpath ${SYSTEMROOT})/system32 &&
-        export MAKEFLAGS=-j$(nproc) &&
-        cd build &&
-        (export PATH=${{ matrix.target }}/winsup/testsuite/testinst/bin:${PATH} && cmd /c $(cygpath -wa ${{ matrix.target }}/winsup/cygserver/cygserver) &) &&
-        (cd ${{ matrix.target }}/winsup; make check AM_COLOR_TESTS=always)
-      shell: C:\cygwin\bin\bash.exe --noprofile --norc -eo pipefail '{0}'
-
-    # upload test logs to facilitate investigation of problems
-    - name: Upload test logs
-      uses: actions/upload-artifact@v4
-      with:
-        name: testlogs
-        path: |
-          build/${{ matrix.target }}/winsup/testsuite/**/*.log
-          build/${{ matrix.target }}/winsup/testsuite/**/*.trs
-      if: ${{ !cancelled() }}
-
-    # workaround problems with actions/checkout post-run step using cygwin git
-    - name: Avoid actions/checkout post-run step using Cygwin git
-      run: bash -c 'rm /usr/bin/git.exe'
diff --git a/winsup/cygwin/Makefile.am b/winsup/cygwin/Makefile.am
index 41190bdb7a..f30cfa5652 100644
--- a/winsup/cygwin/Makefile.am
+++ b/winsup/cygwin/Makefile.am
@@ -620,8 +620,8 @@ $(NEW_DLL_NAME): $(LDSCRIPT) libdll.a $(VERSION_OFILES) $(LIBSERVER)\
 	$(newlib_build)/libm.a \
 	$(newlib_build)/libc.a \
 	-lgcc -lkernel32 -lntdll -Wl,-Map,msys.map
-	@$(MKDIR_P) ${target_builddir}/winsup/testsuite/testinst/bin/
-	$(AM_V_at)$(INSTALL_PROGRAM) $(NEW_DLL_NAME) ${target_builddir}/winsup/testsuite/testinst/bin/$(DLL_NAME)
+	@$(MKDIR_P) ${target_builddir}/winsup/testsuite/testinst/usr/bin/
+	$(AM_V_at)$(INSTALL_PROGRAM) $(NEW_DLL_NAME) ${target_builddir}/winsup/testsuite/testinst/usr/bin/$(DLL_NAME)
 
 # msys-2.0 import library
 toolopts=--cpu=@target_cpu@ --ar=@AR@ --as=@AS@ --nm=@NM@ --objcopy=@OBJCOPY@
diff --git a/winsup/testsuite/Makefile.am b/winsup/testsuite/Makefile.am
index 8f2967a6dc..915981a1be 100644
--- a/winsup/testsuite/Makefile.am
+++ b/winsup/testsuite/Makefile.am
@@ -318,7 +318,7 @@ check_PROGRAMS = \
 # flags for linking against the just built implib
 # TODO: use -nostdinc and to-be-installed headers as well?
 LDFLAGS_FOR_TESTDLL = -nodefaultlibs
-LDADD_FOR_TESTDLL = $(builddir)/../cygwin/libcygwin.a -lgcc -lkernel32 -luser32
+LDADD_FOR_TESTDLL = $(builddir)/../cygwin/libmsys-2.0.a -lgcc -lkernel32 -luser32
 
 # flags for test executables
 AM_CPPFLAGS = -I$(srcdir)/libltp/include
@@ -334,16 +334,24 @@ TESTS = $(check_PROGRAMS) \
 
 # expected fail tests
 XFAIL_TESTS = \
+	winsup.api/ltp/access01 \
+	winsup.api/ltp/access05 \
+	winsup.api/ltp/chmod01 \
 	winsup.api/ltp/setgroups01 \
 	winsup.api/ltp/setuid02 \
+	winsup.api/ltp/stat02 \
+	winsup.api/ltp/symlink01 \
+	winsup.api/ltp/symlink03 \
+	winsup.api/ltp/symlink05 \
 	winsup.api/ltp/ulimit01 \
+	winsup.api/ltp/umask03 \
 	winsup.api/ltp/unlink08 \
 	winsup.api/samples/sample-fail
 
 # cygrun.sh test-runner script, and variables used by it:
 LOG_COMPILER = $(srcdir)/cygrun.sh
 
-export runtime_root=$(abs_builddir)/testinst/bin
+export runtime_root=$(abs_builddir)/testinst/usr/bin
 export cygrun=$(builddir)/mingw/cygrun
 
 # Set up things in the Cygwin 'installation' at testsuite/testinst/ to provide
@@ -365,9 +373,9 @@ export cygrun=$(builddir)/mingw/cygrun
 
 check-local:
 	$(MKDIR_P) ${builddir}/testinst/tmp
-	cd ${builddir}/testinst/bin && cp /usr/libexec/busybox/bin/busybox.exe sh.exe
-	cd ${builddir}/testinst/bin && cp /usr/libexec/busybox/bin/busybox.exe sleep.exe
-	cd ${builddir}/testinst/bin && cp /usr/libexec/busybox/bin/busybox.exe ls.exe
+	cd ${builddir}/testinst/usr/bin && cp /usr/bin/busybox.exe sh.exe
+	cd ${builddir}/testinst/usr/bin && cp /usr/bin/busybox.exe sleep.exe
+	cd ${builddir}/testinst/usr/bin && cp /usr/bin/busybox.exe ls.exe
 
 # target to build all the programs needed by check, without running check
 check_programs: $(check_PROGRAMS)
diff --git a/winsup/testsuite/cygrun.sh b/winsup/testsuite/cygrun.sh
index bf1d5cc6b5..5479543ab3 100755
--- a/winsup/testsuite/cygrun.sh
+++ b/winsup/testsuite/cygrun.sh
@@ -11,7 +11,7 @@ export PATH="$runtime_root:${PATH}"
 if [ "$1" = "./mingw/cygload" ]
 then
     windows_runtime_root=$(cygpath -m $runtime_root)
-    $cygrun "$exe -v -cygwin $windows_runtime_root/cygwin1.dll"
+    MSYS_NO_PATHCONV=1 $cygrun "$exe -v -cygwin $windows_runtime_root/msys-2.0.dll"
 else
     cygdrop $cygrun $exe
 fi
diff --git a/winsup/testsuite/libltp/lib/search_path.c b/winsup/testsuite/libltp/lib/search_path.c
index f6936094a1..3e89fe3c0c 100644
--- a/winsup/testsuite/libltp/lib/search_path.c
+++ b/winsup/testsuite/libltp/lib/search_path.c
@@ -139,7 +139,11 @@ printf("search_path: cmd = %s, access_mode = %d, fullpath = %d\n", cmd, access_m
 			PATH_MAX);
 		    return -1;
 		}
-		sprintf(res_path, "%s/%s", curpath, cmd);
+		/* Avoid a leading "//": on Cygwin/MSYS2 a path starting with
+		   "//" denotes a UNC network path.  When cwd is the root "/"
+		   (as in the MSYS2 testsuite install-root) "%s/%s" would yield
+		   "//cmd"; collapse curpath to "" so we emit "/cmd" instead. */
+		sprintf(res_path, "%s/%s", strcmp(curpath, "/") ? curpath : "", cmd);
 	    }
 	    else
 	        strcpy(res_path, cmd);
@@ -202,7 +206,8 @@ printf("search_path: tmppath = %s\n", tmppath);
 	    continue;
 	}
 
-	sprintf(res_path, "%s/%s", tmppath, cmd);
+	/* Same UNC-path guard as above for the PATH-scan branch. */
+	sprintf(res_path, "%s/%s", strcmp(tmppath, "/") ? tmppath : "", cmd);
 #if DEBUG
 printf("search_path: res_path = '%s'\n", res_path);
 #endif