diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index b8e89d3..c05ed24 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -10,20 +10,29 @@ env:
 
 jobs:
 
-  gcc_build:
-    name: GCC-${{ matrix.gcc_v}} (${{ matrix.os }})
+  build:
+    name: ${{ matrix.toolchain.compiler }}-${{ matrix.toolchain.version }} (${{ matrix.os }})
     runs-on: ${{ matrix.os }}
     env:
-      FFLAGS: --coverage -fprofile-abs-path
-      LDFLAGS: --coverage
+      # Only collect test coverage with gfortran
+      FFLAGS: ${{ matrix.toolchain.compiler == 'gcc' && '--coverage -fprofile-abs-path' || '' }}
+      LDFLAGS: ${{ matrix.toolchain.compiler == 'gcc' && '--coverage' || '' }}
     strategy:
       fail-fast: false
       matrix:
-         gcc_v: [latest]
-         os: [ubuntu-24.04, macos-15, macos-15-intel]
-         include:
+        os: [ubuntu-24.04]
+        toolchain:
+          - {compiler: gcc, version: '15'}
+          - {compiler: intel, version: latest}
+          - {compiler: nvidia-hpc, version: latest}
+          - {compiler: aocc, version: latest}
+        include:
+          - os: ubuntu-22.04
+            toolchain: {compiler: intel-classic, version: '2021.10'}
+          - os: macos-26
+            toolchain: {compiler: gcc, version: '15'}
           - os: ubuntu-22.04
-            gcc_v: 9
+            toolchain: {compiler: gcc, version: '9'}
 
     steps:
     - uses: actions/checkout@v6
@@ -33,8 +42,8 @@ jobs:
     - uses: fortran-lang/setup-fortran@v1
       id: setup-fortran
       with:
-        compiler: gcc
-        version: ${{ matrix.gcc_v }}
+        compiler: ${{ matrix.toolchain.compiler }}
+        version: ${{ matrix.toolchain.version }}
 
       # Python is needed for tests
     - uses: actions/setup-python@v6
@@ -43,9 +52,6 @@ jobs:
 
     - name: Configure
       run: ./configure.sh
-      env:
-        FC: gfortran${{ matrix.os == 'macos-15-intel' && '-14' || '' }}
-
     - name: Build
       run: make -j
 
@@ -77,7 +83,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-         gcc_v: [14]
+         gcc_v: [15]
          os: [ubuntu-24.04]
 
     steps:
@@ -100,41 +106,8 @@ jobs:
       run: make test
 
 
-  intel_build:
-    name: ${{ matrix.toolchain.compiler }}-${{ matrix.toolchain.version }} build
-    runs-on: ubuntu-22.04
-    env:
-      FFLAGS: -O1 -g0
-    strategy:
-      fail-fast: false
-      matrix:
-        toolchain:
-          - {compiler: intel, version: latest}
-          - {compiler: intel-classic, version: '2021.10'}
-
-    steps:
-    - uses: actions/checkout@v6
-
-    - uses: fortran-lang/setup-fortran@v1
-      id: setup-fortran
-      with:
-        compiler: ${{ matrix.toolchain.compiler }}
-        version: ${{ matrix.toolchain.version }}
-
-    - name: Configure
-      run: ./configure.sh
-
-    - name: Build
-      run: make -j
-
-    - name: Unit tests
-      run: make unittest
-
-    - name: End-to-end tests
-      run: make test
-
   cmake_build:
-    name: CMake ${{ matrix.toolchain.compiler }}-${{ matrix.toolchain.version }} zero
+    name: CMake ${{ matrix.toolchain.compiler }}-${{ matrix.toolchain.version }}
     runs-on: ubuntu-24.04
     strategy:
       fail-fast: false
diff --git a/configure.sh b/configure.sh
index fe7db41..6b69d08 100755
--- a/configure.sh
+++ b/configure.sh
@@ -40,17 +40,19 @@ if [[ -z $FC ]]; then
 fi
 
 # This is a very crude heuristic
-comp=$(basename $FC)
+comp=$(basename "$FC")
 if [[ "$comp" = ifx || "$comp" = ifort || "$comp" = mpiifort ]]; then
     FCTYPE=intel
-else
+elif [[ "$comp" = gfortran ]]; then
     FCTYPE=gnu
+else
+    FCTYPE=unknown
 fi
 
 # Set default FFLAGS
 if [[ $FCTYPE = intel ]]; then
     DEFAULT_FFLAGS="-i4 -check bounds,nouninit,noarg_temp_created -g -traceback -O0 -heap-arrays"
-else
+elif [[ $FCTYPE = gnu ]]; then
     warning_flags="-Wall -Wno-unused-dummy-argument -Wno-integer-division -Wno-unused-function -Wno-maybe-uninitialized"
     # TODO: We should probably trap also "invalid" floating-point exception,
     # but need to fix some tests first that currently trigger them :-(
diff --git a/src/modules/Makefile b/src/modules/Makefile
index 93d50c8..502f942 100644
--- a/src/modules/Makefile
+++ b/src/modules/Makefile
@@ -51,7 +51,11 @@ endif
 # Warning: Fortran 2018 deleted feature: DO termination statement which is not END DO or CONTINUE with label 120 at (1)
 EispackModule.o: EispackModule.f
 	@echo "Compiling $<"
-	@$(FC) $(FFLAGS) $(INCFLAGS) -std=legacy -Wno-maybe-uninitialized -c $<
+ifeq ($(FC),gfortran)
+	@$(FC) $(FFLAGS) $(INCFLAGS) -std=legacy -c $<
+else
+	@$(FC) $(FFLAGS) $(INCFLAGS) -c $<
+endif
 
 RandomModule.o: RandomModule.f90 GlobalModule.o
 
diff --git a/src/modules/TrajectoryIOModule.f90 b/src/modules/TrajectoryIOModule.f90
index 44264ca..4f63280 100644
--- a/src/modules/TrajectoryIOModule.f90
+++ b/src/modules/TrajectoryIOModule.f90
@@ -176,10 +176,7 @@ subroutine FMS_WriteFTrajDump(T)
       integer(DefInt), save :: units(MaxTrajLimit) = 0 ! this keeps track of the
       ! unit number of the files
 
-      integer(kind=DefInt) :: i, j
-
-1     format(a10, 4000a10)
-2     format(f10.2, 4000f10.4)
+      integer(kind=DefInt) :: i
 
       ntraj = T%TrajID
       iunit = units(ntraj)
@@ -194,21 +191,42 @@ subroutine FMS_WriteFTrajDump(T)
             open (newunit=iunit, file=trim(file_name), position='append')
          else
             open (newunit=iunit, file=trim(file_name))
-            write (iunit, 1) '# Time', ([ &
-                                        FMS_NumberedFileName('pos', i)//'x', &
-                                        FMS_NumberedFileName('pos', i)//'y', &
-                                        FMS_NumberedFileName('pos', i)//'z'], i=1, T%NumParticles), &
-               ([FMS_NumberedFileName('mom', i)//'x', &
-                 FMS_NumberedFileName('mom', i)//'y', &
-                 FMS_NumberedFileName('mom', i)//'z'], i=1, T%NumParticles), &
+            ! Header.
+            ! The is a single line with columns for all particles.
+            ! " Time ... positions ... momenta ... phase ... stateID"
+            write (unit=iunit, fmt='(a10)', advance='no') ' # Time'
+            do i = 1, t%numParticles
+               write (unit=iunit, fmt='(3(a10))', advance='no') &
+                  FMS_NumberedFileName('pos', i)//'x', &
+                  FMS_NumberedFileName('pos', i)//'y', &
+                  FMS_NumberedFileName('pos', i)//'z'
+            end do
+            do i = 1, t%numParticles
+               write (unit=iunit, fmt='(3(a10))', advance='no') &
+                  FMS_NumberedFileName('mom', i)//'x', &
+                  FMS_NumberedFileName('mom', i)//'y', &
+                  FMS_NumberedFileName('mom', i)//'z'
+            end do
+            write (unit=iunit, fmt='(5(a10))') &
                'Phase', 'AmpReal', 'AmpImag', 'AmpNorm', 'StateID'
+            ! Data to follow ...
          end if
          units(ntraj) = iunit
       end if
 
-      write (iunit, 2) T%get_time(), (T%Particle(i)%get_pos(), i=1, T%NumParticles), &
-         ((T%Particle(i)%get_mom(j), j=1, T%Particle(i)%NumDimensions), i=1, T%NumParticles), &
-         T%Phase, real(T%Amplitude), aimag(T%Amplitude), FMS_Weight(T), dble(T%StateID)
+      ! Data ...
+      ! (time is a f10.2 format; others are f10.4; stateID could be int)
+      write (unit=iunit, fmt='(f10.2)', advance='no') t%get_time()
+      do i = 1, t%numParticles
+         write (unit=iunit, fmt='(3(f10.4))', advance='no') &
+            t%particle(i)%get_pos()
+      end do
+      do i = 1, t%numParticles
+         write (unit=iunit, fmt='(3(f10.4))', advance='no') &
+            t%particle(i)%get_mom()
+      end do
+      write (unit=iunit, fmt='(5(f10.4))') &
+         t%phase, t%amplitude%re, t%amplitude%im, FMS_Weight(t), real(t%stateID)
 
    end subroutine FMS_WriteFTrajDump
 !>
@@ -715,14 +733,8 @@ subroutine FMS_WriteFDipole(T, file_name, first_time)
       integer(kind=DefInt) :: iunit
       logical :: file_existed
 
-      integer :: nstate
       integer(kind=DefInt) :: k
 
-1     format(a10, 50(a10))
-2     format(f10.2, 1000f11.6)
-
-      nstate = T%NumStates
-
       long_file_name = trim(FMSWorkingDir)//file_name
       file_existed = .true.
       if (first_time) then
@@ -731,11 +743,20 @@ subroutine FMS_WriteFDipole(T, file_name, first_time)
 
       if (.not. file_existed) then
          open (newunit=iunit, file=trim(long_file_name))
-         write (iUnit, 1) '#Time', &
-            (FMS_NumberedFileName('Mag', k), k=1, nstate), &
-            ([FMS_NumberedFileName('D', k)//'x', &
-              FMS_NumberedFileName('D', k)//'y', &
-              FMS_NumberedFileName('D', k)//'z'], k=1, nstate)
+         ! Header
+         ! "Time ... magnitudes ... components"
+         write (unit=iunit, fmt='(a10)', advance='no') '#Time'
+         do k = 1, t%numStates
+            write (unit=iunit, fmt='(a10)', advance='no') &
+               FMS_NumberedFileName('Mag', k)
+         end do
+         do k = 1, t%numStates
+            write (unit=iunit, fmt='(3(a10))', advance='no') &
+               FMS_NumberedFileName('D', k)//'x', &
+               FMS_NumberedFileName('D', k)//'y', &
+               FMS_NumberedFileName('D', k)//'z'
+         end do
+         write (unit=iunit, fmt=*) ! end of header line
       else
          open (newunit=iunit, file=trim(long_file_name), position='append')
       end if
@@ -743,9 +764,16 @@ subroutine FMS_WriteFDipole(T, file_name, first_time)
       ! 4. Write dipoles,
       ! This was writing the square of the dipole, was that
       ! intentional?
-      write (IUnit, 2) T%get_time(), &
-         (sqrt(sum(FMS_Dipole(T, k)**2)), k=1, T%NumStates), &
-         (FMS_Dipole(T, k), k=1, T%NumStates)
+
+      do k = 1, t%numStates
+         write (unit=iunit, fmt='(f11.6)', advance='no') &
+            sqrt(sum(FMS_Dipole(t, k)**2))
+      end do
+      do k = 1, t%numStates
+         write (unit=iunit, fmt='(3(f11.6))', advance='no') &
+            FMS_Dipole(t, k)
+      end do
+      write (unit=iunit, fmt=*) ! end of data line
 
       close (IUnit)
 
@@ -893,29 +921,42 @@ subroutine FMS_WriteFTDipole(T)
       integer(DefInt) :: iunit
       integer(DefInt), save :: units(MaxTrajLimit) = 0 ! this keeps track of the
       logical :: file_existed
-      integer :: nstate, j
+      integer :: j
 
-1     format(a10, 50(a10))
-2     format(f10.2, 50(1x, f9.5))
-
-      nstate = T%NumStates
       iunit = units(T%TrajID)
 
       if (iunit == 0) then
          call FMS_OpenFile(FMS_NumberedFileName('TDip', T%TrajID), iunit, file_existed)
          if (.not. file_existed) then
-            write (iUnit, 1) '#Time', &
-               (FMS_NumberedFileName('Mag', j), j=2, nstate), &
-               ([FMS_NumberedFileName('TD', j)//'x', &
-                 FMS_NumberedFileName('TD', j)//'y', &
-                 FMS_NumberedFileName('TD', j)//'z'], j=2, nstate)
+            ! Header ...
+            write (unit=iunit, fmt='(a10)', advance='no') '#Time'
+            do j = 2, t%numStates
+               write (unit=iunit, fmt='(a10)', advance='no') &
+                  FMS_NumberedFileName('Mag', j)
+            end do
+            do j = 2, t%numStates
+               write (unit=iunit, fmt='(3(a10))', advance='no') &
+                  FMS_NumberedFileName('TD', j)//'x', &
+                  FMS_NumberedFileName('TD', j)//'y', &
+                  FMS_NumberedFileName('TD', j)//'z'
+            end do
+            write (unit=iunit, fmt=*) ! End of header line
          end if
          units(T%TrajID) = iunit
       end if
 
       ! 4. Write transition dipole
-      write (iunit, 2) T%get_time(), (sqrt(sum(FMS_TransDipole(T, j)**2)), j=2, nstate), &
-         (FMS_TransDipole(T, j), j=2, nstate)
+
+      write (unit=iunit, fmt='(f10.2)', advance='no') t%get_time()
+      do j = 2, t%numStates
+         write (unit=iunit, fmt='(1x,f9.5)', advance='no') &
+            sqrt(sum(FMS_TransDipole(t, j)**2))
+      end do
+      do j = 2, t%numStates
+         write (unit=iunit, fmt='(3(1x,f9.5))', advance='no') &
+            FMS_TransDipole(t, j)
+      end do
+      write (unit=iunit, fmt=*) ! End of data line
 
    end subroutine FMS_WriteFTDipole
 !>