diff --git a/.travis.yml b/.travis.yml
index 83470ab45..80434fa73 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,39 +1,39 @@
 language: cpp
 
 notifications:
   email:
     recipients:
       - akohlmey@gmail.com
     on_successs: change
     on_failure: always
 
 compiler:
   - gcc
   - clang
 
 before_install:
   - sudo apt-get update -qq
   - sudo apt-get install -y mpi-default-bin mpi-default-dev libfftw3-dev libjpeg-dev libpng12-dev python-dev
 
 env:
-  - MACH=serial LMPFLAGS="-sf off" LMP_INC="-DLAMMPS_GZIP -DLAMMPS_PNG -DLAMMPS_JPEG" JPG_LIB="-ljpeg -lpng -lz"
-  - MACH=mpi MPICMD="mpirun -np 4" LMPFLAGS="-pk omp 2 -sf omp" LMP_INC="-DFFT_FFTW3 -DLAMMPS_GZIP -DLAMMPS_PNG -DLAMMPS_JPEG -DLAMMPS_SMALLBIG" JPG_LIB="-lfftw3 -ljpeg -lpng -lz"
-  - MACH=mpi MPICMD="mpirun -np 4" LMPFLAGS="-pk omp 2 -sf omp" LMP_INC="-DFFT_FFTW3 -DLAMMPS_GZIP -DLAMMPS_PNG -DLAMMPS_JPEG -DLAMMPS_SMALLSMALL" JPG_LIB="-lfftw3 -ljpeg -lpng -lz"
-  - MACH=mpi MPICMD="mpirun -np 4" LMPFLAGS="-pk omp 2 -sf omp" LMP_INC="-DFFT_FFTW3 -DLAMMPS_GZIP -DLAMMPS_PNG -DLAMMPS_JPEG -DLAMMPS_BIGBIG" JPG_LIB="-lfftw3 -ljpeg -lpng -lz"
+  - MACH=serial LMPFLAGS="-sf off" LMP_INC="-DFFT_KISSFFT -DLAMMPS_GZIP -DLAMMPS_PNG -DLAMMPS_JPEG" JPG_LIB="-ljpeg -lpng -lz"
+  - MACH=mpi MPICMD="mpirun -np 2" LMPFLAGS="-pk omp 2 -sf omp" LMP_INC="-DFFT_FFTW3 -DLAMMPS_GZIP -DLAMMPS_PNG -DLAMMPS_JPEG -DLAMMPS_SMALLBIG" JPG_LIB="-lfftw3 -ljpeg -lpng -lz"
+  - MACH=mpi MPICMD="mpirun -np 4" LMPFLAGS="-pk omp 1 -sf omp" LMP_INC="-DFFT_KISSFFT -DLAMMPS_GZIP -DLAMMPS_PNG -DLAMMPS_JPEG -DLAMMPS_SMALLSMALL" JPG_LIB="-ljpeg -lpng -lz"
+  - MACH=mpi MPICMD="mpirun -np 1" LMPFLAGS="-pk omp 4 -sf omp" LMP_INC="-DFFT_FFTW3 -DLAMMPS_GZIP -DLAMMPS_PNG -DLAMMPS_JPEG -DLAMMPS_BIGBIG" JPG_LIB="-lfftw3 -ljpeg -lpng -lz"
 
 install:
   - export OMPI_CC=$CC
   - export OMPI_CXX=$CXX
   - test "$MACH" = "mpi" && export COMP="mpicxx -fopenmp" || export COMP="$CXX"
 
 script:
   - make -C src clean-all
   - make -C src yes-all
   - make -C src no-lib
   - make -C src yes-user-smd yes-user-molfile yes-compress yes-python
   - make -C lib/colvars -f Makefile.g++ CXX="${COMP}"
   - make -C lib/poems -f Makefile.g++ CXX="${COMP}"
   - make -C lib/voronoi -f Makefile.g++ CXX="${COMP}"
   - make -C src yes-poems yes-voronoi yes-user-colvars 
   - test "$MACH" = mpi && make -C src yes-mpiio yes-user-lb || true
   - make -C src test-${MACH} MPICMD="${MPICMD}" CC="${COMP}" LINK="${COMP}" LMP_INC="${LMP_INC}" JPG_LIB="${JPG_LIB}" TAG="${TAG}-$CC" LMPFLAGS="${LMPFLAGS}"