diff --git a/regtest/basic/rt-ghost-1/config b/regtest/basic/rt-ghost-1/config
index 83a65f73deebe98818dbfac0e5425d34d2ae4ece..7b2cb650eca9bfb72f527abb05ddd223845c270d 100644
--- a/regtest/basic/rt-ghost-1/config
+++ b/regtest/basic/rt-ghost-1/config
@@ -1,3 +1,3 @@
 type=driver
-plumed_needs="matheval"
 arg="--plumed plumed.dat --ixyz trajectory.xyz --dump-forces ff --dump-forces-fmt=%10.6f --dump-full-virial"
+export PLUMED_USE_LEPTON=yes
diff --git a/regtest/basic/rt-maxent-1/config b/regtest/basic/rt-maxent-1/config
index 513d265c869bb65e1bd07da88e3ab255321a7323..abf1fa487167a6bdeba340ddc13b6cf79a0e2cf2 100644
--- a/regtest/basic/rt-maxent-1/config
+++ b/regtest/basic/rt-maxent-1/config
@@ -1,3 +1,3 @@
 type=driver
-plumed_needs="matheval"
 arg="--plumed plumed.dat --mf_xtc traj.xtc --dump-forces forces --dump-forces-fmt=%8.4f"
+export PLUMED_USE_LEPTON=yes
diff --git a/regtest/basic/rt-maxent-2/config b/regtest/basic/rt-maxent-2/config
index 513d265c869bb65e1bd07da88e3ab255321a7323..8d96fd6b8431a783fa3daea5750f3a6ceeacb8a7 100644
--- a/regtest/basic/rt-maxent-2/config
+++ b/regtest/basic/rt-maxent-2/config
@@ -1,3 +1,4 @@
 type=driver
-plumed_needs="matheval"
 arg="--plumed plumed.dat --mf_xtc traj.xtc --dump-forces forces --dump-forces-fmt=%8.4f"
+export PLUMED_USE_LEPTON=yes
+
diff --git a/regtest/basic/rt-maxent-3/config b/regtest/basic/rt-maxent-3/config
index c19de798f61b0fddd8483b71f4a109280861b366..cf1eacb4d9aa90082258c6789bca47bb32ea75ea 100644
--- a/regtest/basic/rt-maxent-3/config
+++ b/regtest/basic/rt-maxent-3/config
@@ -1,5 +1,6 @@
 mpiprocs=6
 type=driver
-plumed_needs="matheval"
 # this is to test a different name
 arg="--plumed plumed.dat --mf_xtc traj.xtc --dump-forces forces --multi 6 --dump-forces-fmt=%8.4f"
+export PLUMED_USE_LEPTON=yes
+
diff --git a/regtest/basic/rt-maxent-4/config b/regtest/basic/rt-maxent-4/config
index 2dacd25cd89921389b17a1a6019890a5751e11b0..2cd7d1f8cca7e0781d485f9a5f8b946052234ee6 100644
--- a/regtest/basic/rt-maxent-4/config
+++ b/regtest/basic/rt-maxent-4/config
@@ -1,4 +1,4 @@
 mpiprocs=6
 type=driver
-plumed_needs="matheval"
 arg="--plumed plumed.dat --mf_xtc traj.xtc --dump-forces forces --dump-forces-fmt=%8.4f --debug-dd"
+export PLUMED_USE_LEPTON=yes
diff --git a/regtest/basic/rt-maxent-5/config b/regtest/basic/rt-maxent-5/config
index 3d1aed0c16555f2509e379339e224f2b928d378a..16036960e46df27dd70d14d0dfbbfe62535dc50a 100644
--- a/regtest/basic/rt-maxent-5/config
+++ b/regtest/basic/rt-maxent-5/config
@@ -1,4 +1,4 @@
 mpiprocs=6
 type=driver
-plumed_needs="matheval"
 arg="--plumed plumed.dat --mf_xtc traj.xtc --dump-forces forces --multi 3 --dump-forces-fmt=%8.4f --debug-dd"
+export PLUMED_USE_LEPTON=yes
diff --git a/regtest/basic/rt23/config b/regtest/basic/rt23/config
index 36ac598179e9e45f286fbfc5db818537a5b30621..4fae92952b661a103d125802ec6c1a6d036a34cc 100644
--- a/regtest/basic/rt23/config
+++ b/regtest/basic/rt23/config
@@ -1,4 +1,5 @@
 type=driver
 # this is to test a different name
 arg="--plumed plumed.dat --ixyz trajectory.xyz --dump-forces forces.xyz --dump-forces-fmt=%10.6f"
-plumed_needs="matheval"
+export PLUMED_USE_LEPTON=yes
+
diff --git a/regtest/basic/rt63c-mpi/config b/regtest/basic/rt63c-mpi/config
index 9e7954b34313fa58bce88d8294912400f67f0ffa..fbe364f0b0b10654c99085eb2dd1a27b57131923 100644
--- a/regtest/basic/rt63c-mpi/config
+++ b/regtest/basic/rt63c-mpi/config
@@ -1,4 +1,4 @@
 type=driver
 mpiprocs=2
-plumed_needs="matheval"
 arg="--plumed plumed.dat --trajectory-stride 10 --timestep 0.005 --igro helix.input.gro --dump-forces ff --dump-full-virial --dump-forces-fmt=%7.4f --debug-dd"
+export PLUMED_USE_LEPTON=yes
diff --git a/regtest/basic/rt63c/config b/regtest/basic/rt63c/config
index 20ada5f7126539dc5784ccabdb4da927c9b423ff..fc77b1e66d84156546fbe0abc8d573cbcf686bfb 100644
--- a/regtest/basic/rt63c/config
+++ b/regtest/basic/rt63c/config
@@ -1,3 +1,3 @@
 type=driver
-plumed_needs="matheval"
 arg="--plumed plumed.dat --trajectory-stride 10 --timestep 0.005 --igro helix.input.gro --dump-forces ff --dump-full-virial --dump-forces-fmt=%7.4f"
+export PLUMED_USE_LEPTON=yes