diff --git a/.github/workflows/amd64-linux.yml b/.github/workflows/amd64-linux.yml
index f1b2742..fd9fff0 100644
--- a/.github/workflows/amd64-linux.yml
+++ b/.github/workflows/amd64-linux.yml
@@ -15,6 +15,8 @@ jobs:
     steps:
       - name: checkout
         uses: actions/checkout@v4
+      - name: preprocess
+        run: make -j$JOBS -C src/ CI=1 preprocess-inplace
 
       - name: check safety
         run: make -j$JOBS -C src/ CI=1 check-safety
@@ -28,6 +30,8 @@ jobs:
     steps:
       - name: checkout
         uses: actions/checkout@v4
+      - name: preprocess
+        run: make -j$JOBS -C src/ CI=1 preprocess-inplace
 
       - name: check speculative constant-time (v1)
         run: make -j$JOBS -C src/ CI=1 check-sct
@@ -41,6 +45,8 @@ jobs:
     steps:
       - name: checkout
         uses: actions/checkout@v4
+      - name: preprocess
+        run: make -j$JOBS -C src/ CI=1 preprocess-inplace
 
       - name: check extraction from Jasmin to EasyCrypt
         run: make -j$JOBS -C src/ CI=1 extract-to-easycrypt
@@ -54,6 +60,8 @@ jobs:
     steps:
       - name: checkout
         uses: actions/checkout@v4
+      - name: preprocess
+        run: make -j$JOBS -C src/ CI=1 preprocess-inplace
 
       - name: check compilation of libformosa25519.a
         run: make -j$JOBS -C src/ CI=1 libformosa25519.a
@@ -68,6 +76,8 @@ jobs:
     steps:
       - name: checkout
         uses: actions/checkout@v4
+      - name: preprocess
+        run: make -j$JOBS -C src/ CI=1 preprocess-inplace
 
       - name: run tests
         run: make -j$JOBS -C test/
@@ -80,6 +90,8 @@ jobs:
         uses: actions/checkout@v4
         with:
           submodules: recursive
+      - name: preprocess
+        run: make -j$JOBS -C src/ CI=1 preprocess-inplace
 
       - name: run benchmarks
         run: make -j$JOBS -C bench/
@@ -90,6 +102,8 @@ jobs:
     steps:
       - name: checkout
         uses: actions/checkout@v4
+      - name: preprocess
+        run: make -j$JOBS -C src/ CI=1 preprocess-inplace
 
       - name: run proof
         run: make -j$JOBS -C proof/ all-no-report
diff --git a/scripts/releaser/jpp-slim b/scripts/releaser/jpp-slim
new file mode 100755
index 0000000..c084ba7
--- /dev/null
+++ b/scripts/releaser/jpp-slim
@@ -0,0 +1,37 @@
+#!/usr/bin/env perl
+
+use strict;
+use warnings;
+
+our $R = '^'.'[\s]*'.'(?:from[\s]+(\w+)[\s+])?'.'[\s]*'.'require'.'[\s]*'.'"'.'([\w./_-]+)'.'"';
+
+sub jpp_slim_main()
+{ my $f = rp($ARGV[0]);
+  my %i = map { my ($a,$b) = split /:/; $b = rp($b); ($a, $b) } split /;/, $ARGV[1];
+  pp($f, \%i, {});
+}
+
+sub rp { chomp(my $p = `realpath $_[0]`); $p }
+sub ld { open my $f, '<', $_[0]; chomp(my @s = <$f>); @s }
+sub pc { print "//$_\n" }
+sub pn { print "$_\n" }
+
+sub ppl
+{ my ($d, $l, $i, $v) = @_;
+  ($l =~ m/$R/) ?
+  do { pc $l; pp( rp((defined $1)?$i->{$1}."/".$2 : rp($d."/".$2)), $i, $v) } :
+  pn $l
+}
+
+sub pp
+{ my ($f, $i, $v) = @_;
+  return if defined $v->{$f};
+  $v->{$f} = 1;
+  chomp(my $d = `dirname $f`);
+  map { ppl($d, $_, $i, $v) } (ld $f)
+}
+
+unless (caller) { jpp_slim_main(); }
+
+1;
+
diff --git a/src/Makefile b/src/Makefile
index 30831c1..b44d8bd 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -192,7 +192,7 @@ all:
 	$(MAKE) extract-to-easycrypt
 	$(MAKE) libformosa25519.a
 	$(MAKE) libformosa25519.h
-	$(MAKE) reporter
+	$(MAKE) -j1 reporter
 	$(MAKE) err
 
 all-with-preprocess-inplace: CI=1
@@ -204,7 +204,7 @@ all-with-preprocess-inplace:
 	$(MAKE) extract-to-easycrypt
 	$(MAKE) libformosa25519.a
 	$(MAKE) libformosa25519.h
-	$(MAKE) reporter
+	$(MAKE) -j1 reporter
 	$(MAKE) err
 
 
diff --git a/src/Makefile.common b/src/Makefile.common
index cb7f304..a1873f1 100644
--- a/src/Makefile.common
+++ b/src/Makefile.common
@@ -47,7 +47,7 @@ JASMIN ?= jasminc
 
 JEXT ?= jazz
 override JFLAGS += -stack-zero loopSCT -noinsertarraycopy
-JINCLUDE ?= -I formosa25519:$(SRC)
+JINCLUDE ?=-I formosa25519:$(SRC)
 
 JASMIN_COMPILE = ($(JASMIN) $(JFLAGS) $(JINCLUDE) -o $@ $<) $(CI_CMD)
 
@@ -56,9 +56,10 @@ ASSEMBLY_FILES = $(SRCS:%.$(JEXT)=%.s)
 
 # preprocessing vars
 
-JPP ?= $(PROJECT_DIR)/scripts/releaser/jpp
+JPP ?= $(PROJECT_DIR)/scripts/releaser/jpp-slim
+JPP_JINCLUDE := $(subst -I,,$(JINCLUDE))
 PREPROCESSED_FILES := $(SRCS:%.$(JEXT)=%.jpp)
-JASMIN_PREPROCESS = ($(JPP) $(JINCLUDE) -b $(PROJECT_PARENT_DIR)/ -out $@ -in $<) $(CI_CMD)
+JASMIN_PREPROCESS = ($(JPP) $< $(JPP_JINCLUDE) > $@) $(CI_CMD)
 
 
 # -----------------------------------------------------------------------------