diff --git a/app/Makefile b/app/Makefile
index d55f6591..e73cd652 100644
--- a/app/Makefile
+++ b/app/Makefile
@@ -46,11 +46,19 @@ MORE_OBJECTS=
 NO_LTO=0
 
 ifeq ($(DEBUG),1)
+  NO_LTO=1
   DBG_SUBDIR+=dbg
 else
   DBG_SUBDIR+=rel
 endif
 
+ifeq ($(NO_LTO),1)
+  CFLAGS+= -fno-lto
+else
+  CFLAGS+=${CFLAGS_LTO}
+  LDFLAGS_OPT+= ${LDFLAGS_OPT_LTO}
+endif
+
 NO_STDIN=
 ifeq ($(NO_STDIN),1)
   CFLAGS+= -DNO_STDIN
@@ -91,7 +99,6 @@ ifeq ($(DEBUG),0)
       $(echo "No profiling set. To use PGO, compile with PGO=1, then run with data, then compile again with PGO=2")
     endif
   endif
-
 else
   CFLAGS += -g
 endif
@@ -161,12 +168,6 @@ endif
 CLI_OBJECTS=$(addprefix ${CLI_OBJ_PFX},$(addsuffix .o,${CLI_SOURCES}))
 
 CFLAGS+=${CFLAGS_AUTO}
-ifeq ($(NO_LTO),1)
-  CFLAGS+= -fno-lto
-else
-  CFLAGS+=${CFLAGS_LTO}
-  LDFLAGS_OPT+= ${LDFLAGS_OPT_LTO}
-endif
 
 ifeq ($(VERBOSE),1)
   CFLAGS+= ${CFLAGS_VECTORIZE_OPTIMIZED} ${CFLAGS_VECTORIZE_MISSED} ${CFLAGS_VECTORIZE_ALL}
diff --git a/app/benchmark/README.md b/app/benchmark/README.md
index 6af86e8f..57ace323 100644
--- a/app/benchmark/README.md
+++ b/app/benchmark/README.md
@@ -87,7 +87,7 @@ The following utilities were compared:
 * Our test system shown in the above graph was a pre-M1 OSX MBA.
   We also tested on Linux, BSD
   and Windows. In each case, zsv was the fastest, but in some cases the margin
-  was smaller (e.g. 20%+ instead of 50% vs xsv on Win). 
+  was smaller (e.g. 20%+ instead of 50% vs xsv on Win).
 
 ### Results in above graph (pre-M1 OSX MBA)
 
diff --git a/app/builtin/help.c b/app/builtin/help.c
index ebae9fd4..f6bcce3a 100644
--- a/app/builtin/help.c
+++ b/app/builtin/help.c
@@ -16,7 +16,17 @@ static int main_help(int argc, const char *argv[]) {
     "",
     "Usage:",
     "  zsv version: display version info (and if applicable, extension info)",
+#ifndef __EMSCRIPTEN__
     "  zsv (un)register [<extension_id>]: (un)register an extension",
+    "      Registration info is saved in zsv.ini located in a directory determined as:",
+    "        ZSV_CONFIG_DIR environment variable value, if set",
+# if defined(_WIN32)
+    "        LOCALAPPDATA environment variable value, if set",
+    "        otherwise, C:\\temp",
+#else
+    "        otherwise, " PREFIX "/etc",
+# endif
+#endif
     "  zsv help [<command>]",
     "  zsv <command> <options> <arguments>: run a command on data (see below for details)",
     "  zsv <id>-<cmd> <options> <arguments>: invoke command 'cmd' of extension 'id'",
@@ -72,8 +82,8 @@ static int main_help(int argc, const char *argv[]) {
         for(struct zsv_ext_command *cmd = ext->commands; cmd; cmd = cmd->next)
           fprintf(f, "    %s-%s%s%s\n", ext->id, cmd->id, cmd->help ? ": " : "", cmd->help ? cmd->help : "");
       }
-      config_free(&config);
     }
+    config_free(&config);
   }
   if(!printed_init)
     fprintf(f, "\n(No extended commands)\n");
diff --git a/app/builtin/license.c b/app/builtin/license.c
index b3b6b0fa..8090c1ef 100644
--- a/app/builtin/license.c
+++ b/app/builtin/license.c
@@ -11,19 +11,19 @@ static int main_license(int argc, const char *argv[]) {
   (void)(argv);
 
   fprintf(stderr, "Note: for third-party licenses & acknowledgements, run `zsv thirdparty`\n");
-  printf("\n==========================\n");
+  printf("\n====================================================\n");
   printf("ZSV/lib license");
   printf(" ");
-  printf("\n==========================\n");
+  printf("\n====================================================\n");
 
   fwrite(zsv_license_text_MIT, 1, strlen(zsv_license_text_MIT), stdout);
 
   struct cli_config config;
   if(!config_init(&config, 0, 1, 0)) {
     for(struct zsv_ext *ext = config.extensions; ext; ext = ext->next) {
-      printf("\n==========================\n");
+      printf("\n====================================================\n");
       printf("License for extension '%s'", ext->id);
-      printf("\n==========================\n");
+      printf("\n====================================================\n");
       if(ext->license && *ext->license) {
         size_t len = strlen(ext->license);
         fwrite(ext->license, 1, len, stdout);
diff --git a/app/ext_example/Makefile b/app/ext_example/Makefile
index bb51c8b8..d8c70dcf 100644
--- a/app/ext_example/Makefile
+++ b/app/ext_example/Makefile
@@ -46,6 +46,9 @@ else
 endif
 CFLAGS+= ${CFLAGS_PIC}
 
+ifeq ($(ZSV_EXTRAS),1)
+  CFLAGS+= -DZSV_EXTRAS
+endif
 
 DEBUG=0
 ifeq ($(DEBUG),0)
@@ -94,6 +97,10 @@ ${INSTALLED_EXTENSION}: ${TARGET}
 	cp -p $< $@
 endif
 
+CLI=${BUILD_DIR}/bin/cli
+
+RUN_CLI=ZSV_CONFIG_DIR=/tmp ${CLI}
+
 ${BUILD_DIR}/bin/cli:
 	(cd .. && make CC=${CC} CONFIGFILE=${CONFIGFILEPATH} DEBUG=${DEBUG} ${BUILD_DIR}/bin/cli)
 
@@ -102,43 +109,43 @@ ${BUILD_DIR}/objs/utils/%.o:
 
 test: test-1 test-2 test-3 test-4 test-5 test-thirdparty
 
-test-1: test-%:  ${BUILD_DIR}/bin/cli ${TARGET}
-	@${BUILD_DIR}/bin/cli my-echo < ${THIS_LIB_BASE}/data/quoted.csv > /tmp/zsvext-$@.out
+test-1: test-%: ${CLI} ${TARGET}
+	@${RUN_CLI} my-echo < ${THIS_LIB_BASE}/data/quoted.csv > /tmp/zsvext-$@.out
 	@cmp /tmp/zsvext-$@.out test/expected/zsvext-$@.out && ${TEST_PASS} || ${TEST_FAIL}
 
-test-2: test-%:  ${BUILD_DIR}/bin/cli ${TARGET}
-	@${BUILD_DIR}/bin/cli my-echo -t < ${THIS_LIB_BASE}/data/hi.txt > /tmp/zsvext-$@.out
+test-2: test-%: ${CLI} ${TARGET}
+	@${RUN_CLI} my-echo -t < ${THIS_LIB_BASE}/data/hi.txt > /tmp/zsvext-$@.out
 	@cmp /tmp/zsvext-$@.out test/expected/zsvext-$@.out && ${TEST_PASS} || ${TEST_FAIL}
 
-test-3: test-%:  ${BUILD_DIR}/bin/cli ${TARGET}
+test-3: test-%: ${CLI} ${TARGET}
 	@rm -f /tmp/zsvext-$@.out
-	@${BUILD_DIR}/bin/cli unregister my 2>/dev/null 1>/dev/null || [ 1==1 ]
-	@${BUILD_DIR}/bin/cli register my 2>&1 | grep -v [.]so >> /tmp/zsvext-$@.out || [ 1==1 ]
-	@${BUILD_DIR}/bin/cli unregister my 2>&1 | grep -v [.]so >> /tmp/zsvext-$@.out || [ 1==1 ]
-	@${BUILD_DIR}/bin/cli unregister my 2>&1 | grep -v [.]so >> /tmp/zsvext-$@.out || [ 1==1 ]
-	@${BUILD_DIR}/bin/cli help 2>&1 | grep -v [.]so >> /tmp/zsvext-$@.out || [ 1==1 ]
-	@${BUILD_DIR}/bin/cli register my 2>&1 | grep -v [.]so >> /tmp/zsvext-$@.out || [ 1==1 ]
-	@${BUILD_DIR}/bin/cli help 2>&1 | grep -v [.]so >> /tmp/zsvext-$@.out || [ 1==1 ]
+	@${RUN_CLI} unregister my 2>/dev/null 1>/dev/null || [ 1==1 ]
+	@${RUN_CLI} register my 2>&1 | grep -v [.]so >> /tmp/zsvext-$@.out || [ 1==1 ]
+	@${RUN_CLI} unregister my 2>&1 | grep -v [.]so >> /tmp/zsvext-$@.out || [ 1==1 ]
+	@${RUN_CLI} unregister my 2>&1 | grep -v [.]so >> /tmp/zsvext-$@.out || [ 1==1 ]
+	@${RUN_CLI} help 2>&1 | grep -v [.]so >> /tmp/zsvext-$@.out || [ 1==1 ]
+	@${RUN_CLI} register my 2>&1 | grep -v [.]so >> /tmp/zsvext-$@.out || [ 1==1 ]
+	@${RUN_CLI} help 2>&1 | grep -v [.]so >> /tmp/zsvext-$@.out || [ 1==1 ]
 	@cmp /tmp/zsvext-$@.out 2>&1 test/expected/zsvext-$@.out && ${TEST_PASS} || ${TEST_FAIL}
 
-test-4: test-%:  ${BUILD_DIR}/bin/cli ${TARGET}
-	@${BUILD_DIR}/bin/cli unregister my 2>/dev/null 1>/dev/null || [ 1==1 ]
-	@${BUILD_DIR}/bin/cli license > /tmp/zsvext-$@.out 2>> /tmp/zsvext-$@.err
-	@${BUILD_DIR}/bin/cli register my 2>/dev/null 1>/dev/null
-	@${BUILD_DIR}/bin/cli license >> /tmp/zsvext-$@.out 2> /tmp/zsvext-$@.err
+test-4: test-%: ${CLI} ${TARGET}
+	@${RUN_CLI} unregister my 2>/dev/null 1>/dev/null || [ 1==1 ]
+	@${RUN_CLI} license > /tmp/zsvext-$@.out 2>> /tmp/zsvext-$@.err
+	@${RUN_CLI} register my 2>/dev/null 1>/dev/null
+	@${RUN_CLI} license >> /tmp/zsvext-$@.out 2> /tmp/zsvext-$@.err
 	@cmp /tmp/zsvext-$@.out test/expected/zsvext-$@.out && ${TEST_PASS} || ${TEST_FAIL}
 	@cmp /tmp/zsvext-$@.err test/expected/zsvext-$@.err && ${TEST_PASS} || ${TEST_FAIL}
 
-test-5: test-%: ${BUILD_DIR}/bin/cli ${TARGET}
-	@${BUILD_DIR}/bin/cli my-count newline.csv 2>/dev/null > /tmp/zsvext-$@.out
-	@${BUILD_DIR}/bin/cli my-count -q newline.csv 2>/dev/null >> /tmp/zsvext-$@.out
+test-5: test-%:${TARGET}
+	@${RUN_CLI} my-count newline.csv 2>/dev/null > /tmp/zsvext-$@.out
+	@${RUN_CLI} my-count -q newline.csv 2>/dev/null >> /tmp/zsvext-$@.out
 	@cmp /tmp/zsvext-$@.out test/expected/zsvext-$@.out && ${TEST_PASS} || ${TEST_FAIL}
 
-test-thirdparty: test-%: ${BUILD_DIR}/bin/cli ${TARGET}
-	@${BUILD_DIR}/bin/cli unregister my 2>/dev/null 1>/dev/null || [ 1==1 ]
-	@${BUILD_DIR}/bin/cli thirdparty > /tmp/zsvext-$@.out
-	@${BUILD_DIR}/bin/cli register my 2>/dev/null 1>/dev/null
-	@${BUILD_DIR}/bin/cli thirdparty >> /tmp/zsvext-$@.out
+test-thirdparty: test-%: ${CLI} ${TARGET}
+	@${RUN_CLI} unregister my 2>/dev/null 1>/dev/null || [ 1==1 ]
+	@${RUN_CLI} thirdparty > /tmp/zsvext-$@.out
+	@${RUN_CLI} register my 2>/dev/null 1>/dev/null
+	@${RUN_CLI} thirdparty >> /tmp/zsvext-$@.out
 	@cmp /tmp/zsvext-$@.out test/expected/zsvext-$@.out && ${TEST_PASS} || ${TEST_FAIL}
 
 clean:
diff --git a/app/ext_example/configure b/app/ext_example/configure
index d7ed6796..85c7a000 100755
--- a/app/ext_example/configure
+++ b/app/ext_example/configure
@@ -2,7 +2,7 @@
 # Based on the configure script from musl libc, MIT licensed; vis, ISC licensed
 
 usage () {
-cat <<EOF
+    cat <<EOF
 Usage: $0 [OPTION]... [VAR=VALUE]...
 
 To assign environment variables (e.g., CC, CFLAGS...), specify them as
@@ -12,27 +12,30 @@ Defaults for the options are specified in brackets.
 
 Configuration:
   --config-file=FILE      save config to FILE [config.mk]
+  --minimal=yes           do not include extra features (default=no)
 
 Installation directories:
   --prefix=PREFIX         main installation prefix [\$PREFIX or /usr/local]
-  --exec-prefix=EPREFIX   installation prefix for executable files [PREFIX]
+  --exec-prefix=EPREFIX   installation prefix for bin, lib, include [PREFIX]
 
 Fine tuning of the installation directories:
-  --bindir=DIR            user executables [EPREFIX/bin]
   --sharedir=DIR          share directories [PREFIX/share]
   --docdir=DIR            misc. documentation [PREFIX/share/doc]
   --mandir=DIR            man pages [PREFIX/share/man]
 
 Optional features:
+  --try-avx512            use avx512 instructions, if available (not recommended)
   --enable-small-lut      build with smaller lookup tables [no]
   --enable-debug-stderr   build with debug msgs in stderr [no]
-  --enable-clock          build with timing support [no]
   --enable-pie            build with position independent executables [auto]
   --enable-pic            build with position independent shared libraries [auto]
+  --enable-termcap        build with ncurses / termcap (used by \`pretty\` to get console width) [auto]
+  --enable-jq             build with jq (requires installed jq lib) [auto]
 
 Some influential environment variables:
   CC                      C compiler command [detected]
   AWK                     AWK tool command [detected]
+  MAKE                    gmake tool command [detected]
   AR                      archive command [detected]
   RANLIB                  ranlib archive indexer command [detected]
   CFLAGS                  C compiler flags [-Os -pipe ...]
@@ -41,107 +44,184 @@ Some influential environment variables:
 Use these variables to override the choices made by configure.
 
 EOF
-exit 0
+    exit 0
 }
 
 # Helper functions
 
 quote () {
-tr '\n' ' ' <<EOF | grep '^[-[:alnum:]_=,./:]* $' >/dev/null 2>&1 && { echo "$1" ; return 0 ; }
+    tr '\n' ' ' <<EOF | grep '^[-[:alnum:]_=,./:]* $' >/dev/null 2>&1 && { echo "$1" ; return 0 ; }
 $1
 EOF
-printf %s\\n "$1" | sed -e "s/'/'\\\\''/g" -e "1s/^/'/" -e "\$s/\$/'/" -e "s#^'\([-[:alnum:]_,./:]*\)=\(.*\)\$#\1='\2#"
+    printf %s\\n "$1" | sed -e "s/'/'\\\\''/g" -e "1s/^/'/" -e "\$s/\$/'/" -e "s#^'\([-[:alnum:]_,./:]*\)=\(.*\)\$#\1='\2#"
 }
 echo () { printf "%s\n" "$*" ; }
 fail () { echo "$*" ; exit 1 ; }
 fnmatch () { eval "case \"\$2\" in $1) return 0 ;; *) return 1 ;; esac" ; }
 cmdexists () { type "$1" >/dev/null 2>&1 ; }
-trycc () { test -z "$CC" && cmdexists "$1" && CC=$1 ; }
+trycc1 () { test -z "$CC" && cmdexists "$1" && ( "$1" --version | grep -i gcc ) >/dev/null 2>/dev/null && CC=$1 ; }
+trycc2 () { test -z "$CC" && cmdexists "$1" && CC=$1 ; }
 tryar () { test -z "$AR" && cmdexists "$1" && AR=$1 ; }
 tryranlib () { test -z "$RANLIB" && cmdexists "$1" && RANLIB=$1 ; }
 tryawk () { test -z "$AWK" && "$1" 'function works () {return 0} BEGIN{exit works()}' && AWK=$1 ; }
-tryllvmprofdata () { test -z "$LLVM_PROFDATA" && cmdexists "$1" && LLVM_PROFDATA=$1 ; }
+trymake() {
+    if test -z "$MAKE" && cmdexists "$1" ; then
+	v=`$1 --version | grep 'GNU Make' | sed -e 's/.*Make //'`
+	if [ "$v" = "" ] ; then
+	    printf "Found but not using non-GNU make ($1)... "
+	else
+	    MAKE="$1"
+	    maj=`echo $v | cut -d. -f 1`
+	    min=`echo $v | cut -d. -f 2`
+	    if ! test $maj -gt 3 -o '(' $maj -eq 3 -a $min -ge 81 ')' ; then
+		printf "Warning: using make, but version $v < 3.81 has not been tested. "
+	    fi
+	fi
+    fi
+}
 
 stripdir () {
-while eval "fnmatch '*/' \"\${$1}\"" ; do eval "$1=\${$1%/}" ; done
+    while eval "fnmatch '*/' \"\${$1}\"" ; do eval "$1=\${$1%/}" ; done
 }
 
+NO_HAVE=
 trycchdr () {
-printf "checking whether there is a header called %s... " "$2"
-if find $CCSEARCHPATH -name "$2" | grep "/$2$" >/dev/null 2>&1 ; then
-upper2=$(echo "$2" | tr a-z A-Z | tr . _)
-eval "$1=\"\${$1} -DHAVE_\${upper2}\""
-eval "$1=\${$1# }"
-printf "yes\n"
-return 0
-else
-printf "no\n"
-return 1
-fi
+    printf "checking whether there is a header called %s... " "$2"
+    dn=`dirname "$2"`
+    if [ "$dn" != "" ]; then
+	dn="/$dn"
+	bn=`basename "$2"`
+	for x in $CCSEARCHPATH ; do
+	    fnd=$fnd"$x$dn "
+	done
+    else
+	bn="$2"
+	fnd=$CCSEARCHPATH
+    fi
+    upper2=$(echo "$2" | tr a-z A-Z | tr . _ | tr / _)
+    if find $fnd -name "$bn" 2>/dev/null | grep "/$2$" >/dev/null 2>&1 ; then
+        eval "$1=\"\${$1} -DHAVE_\${upper2}\""
+        eval "$1=\${$1# }"
+        printf "yes\n"
+        return 0
+    else
+        printf "no\n"
+        NO_HAVE="$NO_HAVE
+NO_$upper2 = 1"
+        return 1
+    fi
 }
 
 tryccfn () {
-printf "checking whether compiler accepts %s from %s... " "$2" "$3"
-printf "%s\n" $3 | sed 's/\(.*\)/#include <\1>/' > "$tmpc"
-cat >> "$tmpc" <<EOF
+    rm -f "$tmpc"
+    if [ "$5" != "" ] ; then
+        printf "checking whether compiler accepts %s from %s with %s... " "$2" "$3" "$5"
+        echo "$5" >> "$tmpc"
+    else
+        printf "checking whether compiler accepts %s from %s..." "$2" "$3"
+    fi
+    if [ "$3" != "" ]; then
+        printf "%s\n" $3 | sed 's/\(.*\)/#include <\1>/' >> "$tmpc"
+    fi
+    cat >> "$tmpc" <<EOF
 int main() {$2;}
 EOF
-if $CC -o "$tmpo" "$tmpc" >/dev/null 2>&1 ; then
-flag=$(echo "$2" | cut -d'(' -f1 | tr a-z A-Z)
-eval "vars=\$$1"
-if ! printf "%s\n" ${vars} | grep "\-DHAVE_${flag}\$" >/dev/null 2>&1; then
-flag="-DHAVE_${flag}"
-eval "$1=\"\${vars} \${flag}\""
-eval "$1=\${$1# }"
-fi
-printf "yes\n"
-return 0
-else
-printf "no\n"
-return 1
-fi
+    flag=$(echo "$2" | cut -d'(' -f1 | tr a-z A-Z)
+    if $CC -o "$tmpo" "$tmpc" >/dev/null 2>&1 ; then
+        if [ "$4" != "" ] ; then
+            lib=$(echo "$4" | tr a-z A-Z | tr . _)
+            USE_LIBS="$USE_LIBS
+USE_LIB_$lib = 1"
+        fi
+
+        eval "vars=\$$1"
+        if ! printf "%s\n" ${vars} | grep "\-DHAVE_${flag}\$" >/dev/null 2>&1; then
+            flag="-DHAVE_${flag}"
+            eval "$1=\"\${vars} \${flag}\""
+            eval "$1=\${$1# }"
+        fi
+        printf "yes\n"
+        return 0
+    else
+        printf "no\n"
+        NO_HAVE="$NO_HAVE
+NO_$flag = 1"
+        echo "------" >> $CONFIGFILE.log
+        echo "Failed: $CC -o $tmpo tmp.c" >> $CONFIGFILE.log
+        cat "$tmpc" >> $CONFIGFILE.log
+        echo "------" >> $CONFIGFILE.log
+        return 1
+    fi
+}
+
+tryccfn1 () {
+    rm -f "$tmpc"
+    printf "checking whether compiler accepts %s(%s)..." "$2" "$3"
+    cat >> "$tmpc" <<EOF
+int main() {$2($3);}
+EOF
+    flag=$(echo "$2" | cut -d'(' -f1 | tr a-z A-Z)
+    eval "vars=\$$1"
+    if $CC -o "$tmpo" "$tmpc" >/dev/null 2>&1 ; then
+        flag="-DHAVE_${flag}"
+        have=1
+    else
+        flag="-DNO_${flag}"
+        have=0
+    fi
+    if ! printf "%s\n" ${vars} | grep "\-D${flag}\$" >/dev/null 2>&1; then
+        eval "$1=\"\${vars} \${flag}\""
+        eval "$1=\${$1# }"
+    fi
+    if [ "$have" = "1" ]; then
+        printf "yes\n"
+        return 0
+    else
+        printf "no\n"
+        return 1
+    fi
 }
 
 tryflag () {
-printf "checking whether compiler accepts %s... " "$2"
-echo "int main() {return 0;}" > "$tmpc"
-if $CC $CFLAGS_TRY $2 -c -o "$tmpo" "$tmpc" >/dev/null 2>&1 ; then
-printf "yes\n"
-eval "$1=\"\${$1} \$2\""
-eval "$1=\${$1# }"
-return 0
-else
-printf "no\n"
-return 1
-fi
+    printf "checking whether compiler accepts %s... " "$2"
+    echo "int main() {return 0;}" > "$tmpc"
+    if $CC $CFLAGS_TRY $2 -c -o "$tmpo" "$tmpc" >/dev/null 2>&1 ; then
+        printf "yes\n"
+        eval "$1=\"\${$1} \$2\""
+        eval "$1=\${$1# }"
+        return 0
+    else
+        printf "no\n"
+        return 1
+    fi
 }
 
-tryldflag () {
-printf "checking whether linker accepts %s... " "$2"
-echo "int main(){return 0;}" > "$tmpc"
-if $CC $LDFLAGS_TRY "$2" -o "$tmpo" "$tmpc" >/dev/null 2>&1 ; then
-printf "yes\n"
-eval "$1=\"\${$1} \$2\""
-eval "$1=\${$1# }"
-return 0
-else
-printf "no\n"
-return 1
-fi
+tryldflag () { # var, flag, other_arguments (optional)
+    printf "checking whether linker accepts %s... " "$2"
+    echo "int main(){return 0;}" > "$tmpc"
+    if $CC $LDFLAGS "$2" $3 -o "$tmpo" "$tmpc" >/dev/null 2>&1 ; then
+        printf "yes\n"
+        eval "$1=\"\${$1} \$2\""
+        eval "$1=\${$1# }"
+        return 0
+    else
+        printf "no\n"
+        return 1
+    fi
 }
 
 trysharedldflag () {
-printf "checking whether linker accepts %s... " "$2"
-echo "typedef int x;" > "$tmpc"
-if $CC $LDFLAGS_TRY -shared "$2" -o "$tmpo" "$tmpc" >/dev/null 2>&1 ; then
-printf "yes\n"
-eval "$1=\"\${$1} \$2\""
-eval "$1=\${$1# }"
-return 0
-else
-printf "no\n"
-return 1
-fi
+    printf "checking whether linker accepts %s... " "$2"
+    echo "typedef int x;" > "$tmpc"
+    if $CC $LDFLAGS -shared "$2" -o "$tmpo" "$tmpc" >/dev/null 2>&1 ; then
+        printf "yes\n"
+        eval "$1=\"\${$1} \$2\""
+        eval "$1=\${$1# }"
+        return 0
+    else
+        printf "no\n"
+        return 1
+    fi
 }
 
 # Beginning of actual script
@@ -150,60 +230,92 @@ CFLAGS_AUTO=
 CFLAGS_TRY=
 LDFLAGS_AUTO=
 LDFLAGS_TRY=
-CONFIGFILE=config.mk
+CONFIGFILE=$CONFIGFILE
+if [ "$CONFIGFILE" = "" ]; then
+    CONFIGFILE=config.mk
+fi
+
+# check prefixes first, since others may be derived from it unless overridden
 PREFIX=$PREFIX
-if [ "$PREFIX" == "" ]; then
+for arg ; do
+    case "$arg" in
+        --prefix=*) PREFIX=${arg#*=} ;;
+    esac
+done
+if [ "$PREFIX" = "" ]; then
     PREFIX=/usr/local
+elif [ "$PREFIX" = "${PREFIX#/}" ]; then
+    PREFIX="`pwd`/$PREFIX"
 fi
-EXEC_PREFIX='$(PREFIX)'
-BINDIR='$(EXEC_PREFIX)/bin'
-SHAREDIR='$(PREFIX)/share'
+
+EXEC_PREFIX=$EXEC_PREFIX
+for arg ; do
+    case "$arg" in
+        --exec-prefix=*) EXEC_PREFIX=${arg#*=} ;;
+    esac
+done
+if [ "$EXEC_PREFIX" = "" ]; then
+    EXEC_PREFIX=$PREFIX
+elif [ "$EXEC_PREFIX" = "${EXEC_PREFIX#/}" ]; then
+    EXEC_PREFIX="`pwd`/$EXEC_PREFIX"
+fi
+
 DOCDIR='$(PREFIX)/share/doc'
 MANDIR='$(PREFIX)/share/man'
 
+MINIMAL=no
+
 help=yes
 usesmalllut=no
 usedebugstderr=no
-useclock=no
 usepie=auto
 usepic=auto
+usetermcap=auto
+usejq=auto
 
 for arg ; do
-case "$arg" in
---help|-h) usage ;;
---host=*) host=${arg#*=} ;;
---config-file=*) CONFIGFILE=${arg#*=} ;;
---prefix=*) PREFIX=${arg#*=} ;;
---exec-prefix=*) EXEC_PREFIX=${arg#*=} ;;
---bindir=*) BINDIR=${arg#*=} ;;
---sharedir=*) SHAREDIR=${arg#*=} ;;
---docdir=*) DOCDIR=${arg#*=} ;;
---mandir=*) MANDIR=${arg#*=} ;;
---enable-small-lut|--enable-small-lut=yes) usesmalllut=yes ;;
---disable-small-lut|--enable-small-lut=no) usesmalllut=no ;;
---enable-debug-stderr|--enable-debug-stderr=yes) usedebugstderr=yes ;;
---disable-debug-stderr|--enable-debug-stderr=no) usedebugstderr=no ;;
---enable-clock|--enable-clock=yes) useclock=yes ;;
---disable-clock|--enable-clock=no) useclock=no ;;
---enable-pie|--enable-pie=yes) usepie=yes ;;
---enable-pie=auto) usepie=auto ;;
---disable-pie|--enable-pie=no) usepie=no ;;
---enable-pic|enable-pic=yes) usepic=yes ;;
---enable-pic=auto) usepic=auto ;;
---disable-pic|--enable-pic=no) usepic=no ;;
---enable-*|--disable-*|--with-*|--without-*|--*dir=*|--build=*) ;;
--* ) echo "$0: unknown option $arg" ;;
-CC=*) CC=${arg#*=} ;;
-CFLAGS=*) CFLAGS=${arg#*=} ;;
-CPPFLAGS=*) CPPFLAGS=${arg#*=} ;;
-LDFLAGS=*) LDFLAGS=${arg#*=} ;;
-*=*) ;;
-*) ;;
-esac
+    case "$arg" in
+        --help|-h) usage ;;
+        --host=*) host=${arg#*=} ;;
+        --config-file=*) CONFIGFILE=${arg#*=} ;;
+        CONFIGFILE=*) CONFIGFILE=${arg#*=} ;;
+        --prefix=*) ;; # already handled
+        --exec-prefix=*) ;; # already handled EXEC_PREFIX=${arg#*=} ;;
+        --docdir=*) DOCDIR=${arg#*=} ;;
+        --mandir=*) MANDIR=${arg#*=} ;;
+        --minimal|--minimal=yes) MINIMAL=yes;;
+        --try-avx512|--try-avx512=yes) TRY_AVX512=yes;;
+        --enable-small-lut|--enable-small-lut=yes) usesmalllut=yes ;;
+        --disable-small-lut|--enable-small-lut=no) usesmalllut=no ;;
+        --enable-debug-stderr|--enable-debug-stderr=yes) usedebugstderr=yes ;;
+        --disable-debug-stderr|--enable-debug-stderr=no) usedebugstderr=no ;;
+        --enable-pie|--enable-pie=yes) usepie=yes ;;
+        --enable-pie=auto) usepie=auto ;;
+        --disable-pie|--enable-pie=no) usepie=no ;;
+        --enable-pic|enable-pic=yes) usepic=yes ;;
+        --enable-termcap|--enable-termcap=yes) usetermcap=yes ;;
+        --enable-termcap=auto) usetermcap=auto ;;
+        --disable-termcap|--enable-termcap=no) usetermcap=no ;;
+        --enable-jq|--enable-jq=yes) usejq=yes ;;
+        --enable-jq=auto) usejq=auto ;;
+        --disable-jq|--enable-jq=no) usejq=no ;;
+        --enable-pic=auto) usepic=auto ;;
+        --disable-pic|--enable-pic=no) usepic=no ;;
+        --enable-*|--disable-*|--with-*|--without-*|--*dir=*|--build=*) ;;
+        -* ) echo "$0: unknown option $arg" ;;
+        CC=*) CC=${arg#*=} ;;
+        CFLAGS=*) CFLAGS=${arg#*=} ;;
+        CPPFLAGS=*) CPPFLAGS=${arg#*=} ;;
+        LDFLAGS=*) LDFLAGS=${arg#*=} ;;
+        *=*) ;;
+        *) ;;
+    esac
 done
 
-for i in PREFIX EXEC_PREFIX BINDIR SHAREDIR DOCDIR MANDIR ; do
-stripdir $i
+echo "config will be saved to $CONFIGFILE"
+
+for i in PREFIX EXEC_PREFIX DOCDIR MANDIR ; do
+    stripdir $i
 done
 
 #
@@ -212,10 +324,10 @@ done
 i=0
 set -C
 while : ; do i=$(($i+1))
-tmpc="./conf$$-$PPID-$i.c"
-tmpo="./conf$$-$PPID-$i.o"
-2>|/dev/null > "$tmpc" && break
-test "$i" -gt 50 && fail "$0: cannot create temporary file $tmpc"
+             tmpc="./conf$$-$PPID-$i.c"
+             tmpo="./conf$$-$PPID-$i.o"
+             2>|/dev/null > "$tmpc" && break
+             test "$i" -gt 50 && fail "$0: cannot create temporary file $tmpc"
 done
 set +C
 trap 'rm -f "$tmpc" "$tmpo"' EXIT QUIT TERM HUP
@@ -229,20 +341,29 @@ for a in awk gawk mawk nawk; do tryawk "$a"; done
 printf "%s\n" "$AWK"
 test -n "$AWK" || fail "$0: cannot find an AWK tool"
 
+#
+# Find a MAKE tool to use#
+
+printf "checking for MAKE tool... "
+for a in make gmake ; do trymake "$a"; done
+printf "%s\n" "$MAKE"
+test -n "$MAKE" || fail "$0: cannot find a MAKE tool"
+
 #
 # Find a C compiler to use
 #
 printf "checking for C compiler... "
-for c in cc gcc clang; do trycc "$c"; done
+for c in cc gcc gcc-11 gcc-10 gcc-9 clang; do trycc1 "$c"; done
+for c in cc gcc gcc-11 gcc-10 gcc-8 clang; do trycc2 "$c"; done
 printf "%s\n" "$CC"
 test -n "$CC" || fail "$0: cannot find a C compiler"
 
 printf "checking whether C compiler works... "
 echo "typedef int x;" > "$tmpc"
 if output=$($CC $CPPFLAGS $CFLAGS -c -o "$tmpo" "$tmpc" 2>&1) ; then
-printf "yes\n"
+    printf "yes\n"
 else
-fail "no; compiler output follows:\n%s\n" "$output"
+    fail "no; compiler output follows:\n%s\n" "$output"
 fi
 
 #
@@ -252,24 +373,13 @@ CCSEARCHPATH=$(echo | ${CC} -E -Wp,-v - 2>&1 | ${AWK} '/ \//{print substr($0,2);
 
 #
 # Check if it is clang, and the llvm tools instead
-# TODO: PROFDATA triggers specific pgo behaviour
-#       in the Makefile for clang or gcc...
-#       This isn't the most elegant solution right
-#       now...
-#
 compiler=$(${CC} -v 2>&1 | ${AWK} '/ +version +/{for(i=1;i<=NF;i++){if($i=="version"){printf("%s\n",(last=="LLVM")?"clang":last);exit 0;}last=$i;}}')
 if test "$compiler" = "clang"; then
-arlist="$CC-llvm-ar $host-llvm-ar $CC-ar $host-ar llvm-ar ar"
-ranliblist="$CC-llvm-ranlib $host-llvm-ranlib $CC-ranlib $host-ranlib llvm-ranlib ranlib"
-PROFDATA=zsv.profdata
-#printf "checking for llvm-profdata... "
-#tryllvmprofdata llvm-profdata
-#printf "%s\n" "$LLVM_PROFDATA"
-#test -n "$LLVM_PROFDATA" || fail "$0: cannot find llvm-profdata"
+    arlist="$CC-llvm-ar $host-llvm-ar $CC-ar $host-ar llvm-ar ar"
+    ranliblist="$CC-llvm-ranlib $host-llvm-ranlib $CC-ranlib $host-ranlib llvm-ranlib ranlib"
 else
-arlist="$CC-ar $host-$compiler-ar $host-ar $compiler-ar ar"
-ranliblist="$CC-ranlib $host-$compiler-ranlib $host-ranlib $compiler-ranlib $compiler-ranlib ranlib"
-PROFDATA=zsv.profile
+    arlist="$CC-ar $host-$compiler-ar $host-ar $compiler-ar ar"
+    ranliblist="$CC-ranlib $host-$compiler-ranlib $host-ranlib $compiler-ranlib $compiler-ranlib ranlib"
 fi
 
 #
@@ -292,6 +402,13 @@ printf 'checking host system type... '
 test -n "$host" || host=$($CC -dumpmachine 2>/dev/null) || fail "could not determine host"
 printf '%s\n' "$host"
 
+# start the log
+cat >$CONFIGFILE.log <<_ACEOF
+Config log. Invocation command line was
+  $ $0 $@
+
+_ACEOF
+
 #
 # Figure out options to force errors on unknown flags.
 #
@@ -303,16 +420,15 @@ tryldflag LDFLAGS_TRY -Werror=unused-command-line-argument
 tryldflag LDFLAGS_TRY -Werror=ignored-optimization-argument
 
 CFLAGS_STD="-std=gnu11 -D_POSIX_C_SOURCE=200809L -U_XOPEN_SOURCE -D_XOPEN_SOURCE=700"
-CFLAGS_OPT="-DNDEBUG"
+# CFLAGS_OPT="-DNDEBUG"
 MINGW=0
 case "$host" in
-*-*freebsd*) CFLAGS_STD="$CFLAGS_STD -D_BSD_SOURCE -D__BSD_VISIBLE=1" ;;
-*-*netbsd*) CFLAGS_STD="$CFLAGS_STD -D_NETBSD_SOURCE" ;;
-*-*bsd*) CFLAGS_STD="$CFLAGS_STD -D_BSD_SOURCE" ;;
-*-*darwin*) CFLAGS_STD="$CFLAGS_STD -D_DARWIN_C_SOURCE" ;;
-*-*mingw32|*-*msys*|*-windows-gnu)
+    *-*freebsd*) CFLAGS_STD="$CFLAGS_STD -D_BSD_SOURCE -D__BSD_VISIBLE=1" ;;
+    *-*netbsd*) CFLAGS_STD="$CFLAGS_STD -D_NETBSD_SOURCE" ;;
+    *-*bsd*) CFLAGS_STD="$CFLAGS_STD -D_BSD_SOURCE" ;;
+    *-*darwin*) CFLAGS_STD="$CFLAGS_STD -D_DARWIN_C_SOURCE" ;;
+    *-*mingw32|*-*msys*|*-windows-gnu)
 	CFLAGS_STD="$CFLAGS_STD -D__USE_MINGW_ANSI_STDIO"
-	#LDFLAGS_AUTO="-Wl,--export-all-symbols"
 	MINGW=1
 	usepie=no
 	usepic=no
@@ -320,25 +436,32 @@ case "$host" in
 esac
 
 if test "$usepie" = "auto" ; then
-usepie=yes
+    usepie=yes
 fi
 
 if test "$usepic" = "auto" ; then
-usepic=yes
+    usepic=yes
 fi
 
+tryflag CFLAGS_VECTORIZE -fvectorize
+tryflag CFLAGS_VECTORIZE -ftree-vectorize
+tryflag CFLAGS_VECTORIZE_OPTIMIZED -fopt-info-vec-optimized
+tryflag CFLAGS_VECTORIZE_MISSED -fopt-info-vec-missed
+tryflag CFLAGS_VECTORIZE_ALL -fopt-info-vec-all
+tryflag CFLAGS_OPENMP -fopenmp
+
 if test "$usepie" = "yes" ; then
-tryflag CFLAGS_PIE -fpie || tryflag CFLAGS_PIE -fPIE
+    tryflag CFLAGS_PIE -fpie || tryflag CFLAGS_PIE -fPIE
 fi
 
 if test "$usepic" = "yes" ; then
-tryflag CFLAGS_PIC -fpic || tryflag CFLAGS_PIC -fPIC
+    tryflag CFLAGS_PIC -fpic || tryflag CFLAGS_PIC -fPIC
 fi
 
 test "$usepie" = "yes" && tryldflag LDFLAGS_PIE -pie
 
 if test "$usepic" = "yes" ; then
-trysharedldflag LDFLAGS_PIC -fpic || trysharedldflag LDFLAGS_PIC -fPIC
+    trysharedldflag LDFLAGS_PIC -fpic || trysharedldflag LDFLAGS_PIC -fPIC
 fi
 
 test "$usepie" = "no" && tryflag CFLAGS_PIE -fno-pie
@@ -346,73 +469,105 @@ test "$usepic" = "no" && tryflag CFLAGS_PIC -fno-pic
 test "$usepie" = "no" && tryldflag LDFLAGS_PIE -no-pie
 test "$usepic" = "no" && trysharedldflag LDFLAGS_PIC -fno-pic
 
-if test $MINGW -eq 0 ; then
-LDFLAGS_STD="-lc"
-tryflag CFLAGS_AUTO -fstack-protector-all
-case "$CFLAGS_AUTO" in
-*-fstack-protector*) CFLAGS_AUTO="-D_FORTIFY_SOURCE=2"; ;;
-esac
-fi
+#if test $MINGW -eq 0 ; then
+#LDFLAGS_STD="-lc"
+#tryflag CFLAGS_AUTO -fstack-protector-all
+#case "$CFLAGS_AUTO" in
+#*-fstack-protector*) CFLAGS_AUTO="-D_FORTIFY_SOURCE=2"; ;;
+#esac
+#fi
 
 tryflag CFLAGS -pipe
 
 # Try flags to optimize speed
 tryflag CFLAGS -ffunction-sections
 tryflag CFLAGS -fdata-sections
-tryflag CFLAGS_OPT -O3
-tryflag CFLAGS_OPT -march=native
 tryflag CFLAGS_AVX2  -mavx2
 tryflag CFLAGS_CLMUL -mvpclmulqdq
-tryflag CFLAGS_OPT -flto
-tryflag CFLAGS_OPT -fwhole-program
+tryflag CFLAGS_LTO -flto
 tryflag CFLAGS_OPT -fvisibility=hidden
 tryldflag LDFLAGS_AUTO -Wl,--gc-sections
-tryldflag LDFLAGS_OPT -flto
+tryldflag LDFLAGS_OPT_LTO -flto
 tryldflag LDFLAGS_OPT -fwhole-program
-tryldflag LDFLAGS_OPT -O3
 tryldflag LDFLAGS_OPT -march=native
+tryldflag LDFLAGS_OPT -ldl
 
 # Try hardening flags
 if test "$usepie" = "yes" ; then
-case "$LDFLAGS_PIE" in
-*pie*)
-	tryldflag LDFLAGS_PIE -Wl,-z,now
-	tryldflag LDFLAGS_PIE -Wl,-z,relro
-	;;
-esac
+    case "$LDFLAGS_PIE" in
+        *pie*)
+	    tryldflag LDFLAGS_PIE -Wl,-z,now
+	    tryldflag LDFLAGS_PIE -Wl,-z,relro
+	    ;;
+    esac
 fi
 if test "$usepic" = "yes" ; then
-case "$LDFLAGS_PIC" in
-*pic*)
-	tryldflag LDFLAGS_PIC -Wl,-z,now
-	tryldflag LDFLAGS_PIC -Wl,-z,relro
-	;;
-esac
+    case "$LDFLAGS_PIC" in
+        *pic*)
+	    tryldflag LDFLAGS_PIC -Wl,-z,now
+	    tryldflag LDFLAGS_PIC -Wl,-z,relro
+	    ;;
+    esac
 fi
 
 # Check function availability
-tryccfn CFLAGS_AUTO "_alloca(4)" "malloc.h"
-trycchdr CFLAGS_AUTO "alloca.h"
-tryccfn CFLAGS_AUTO "alloca(4)" "stdlib.h"
-tryccfn CFLAGS_AUTO "alloca(4)" "alloca.h"
+if [ "$TRY_AVX512" = "yes" ]; then
+    printf "checking whether avx512 instructions are available..."
+    HAVE_AVX512=
+    tryccfn CFLAGS_AVX_512 "_mm512_movepi8_mask" "immintrin.h" && trycchdr CFLAGS_AVX_512 "immintrin.h" && ( tryccfn CFLAGS_AVX_512 "_blsr_u64" "immintrin.h" || tryccfn CFLAGS_AVX_512 "__blsr_u64" "immintrin.h" ) && tryflag CFLAGS_AVX_512 "-mbmi" && tryflag CFLAGS_AVX_512 "-mavx512bw" && CFLAGS_AVX_512="-mbmi -mavx512bw -DHAVE_AVX512=1" && HAVE_AVX512=1
+    if [ "$HAVE_AVX512" = "1" ]; then
+	echo "yes"
+    else
+	echo "no"
+	echo "WARNING: --try-avx512 option enabled, but no avx512 instruction set available"
+    fi
+fi
+
+tryccfn CFLAGS_AVX_256 "_mm256_movemask_epi8" "immintrin.h" && trycchdr CFLAGS_AVX_256 "immintrin.h" && ( tryccfn CFLAGS_AVX_256 "_blsr_u32" "immintrin.h" || tryccfn CFLAGS_AVX_256 "__blsr_u32" "immintrin.h" ) && CFLAGS_AVX_256="-DHAVE_AVX256=1" && HAVE_AVX256=1
+
+tryccfn CFLAGS_AUTO "memmem" "string.h"
+
+if [ "$usetermcap" = "yes" ] || [ "$usetermcap" = "auto" ] ; then
+    tryccfn TERMCAP_H "tgetent" "termcap.h" && tryldflag LDFLAGS_TERMCAP -ltermcap && tryccfn CFLAGS_AUTO "tgetent" "termcap.h" termcap || \
+            if test "$usetermcap" = "yes"; then
+                echo "Error: --enable-termcap specified, but not found"
+                exit 1
+            fi
+fi
+
+if [ "$usejq" = "yes" ] || [ "$usejq" = "auto" ] ; then
+    tryldflag LDFLAGS_JQ -ljq -L${PREFIX}/lib || \
+        if test "$usejq" = "yes"; then
+            echo "Error: --enable-jq specified, but not found"
+            exit 1
+        fi
+    if ! [ "$LDFLAGS_JQ" = "" ] ; then
+        tryldflag LDFLAGS_JQ -lm
+        tryldflag LDFLAGS_JQ -lshlwapi
+        tryldflag LDFLAGS_JQ -pthread
+    fi
+fi
+
+tryccfn CFLAGS_AUTO "arc4random_uniform" "stdlib.h" || tryccfn CFLAGS_AUTO "rand_s" "stdlib.h" "" "#define _CRT_RAND_S"
+tryccfn1 CFLAGS_AUTO "__builtin_expect" "0,0"
+tryccfn1 CFLAGS_AUTO "__builtin_expect_with_probability" "0,0,0.5"
 
 # Optional features
 if test "$usesmalllut" = "yes" ; then
-	USE_SMALL_LUT=1
+    USE_SMALL_LUT=1
 else
-	USE_SMALL_LUT=0
+    USE_SMALL_LUT=0
 fi
 
 if test "$usedebugstderr" = "yes" ; then
-	USE_DEBUG_STDERR=1
+    USE_DEBUG_STDERR=1
 else
-	USE_DEBUG_STDERR=0
+    USE_DEBUG_STDERR=0
 fi
 
-if test "$useclock" = "yes" ; then
-	USE_CLOCK=1
-else
-	USE_CLOCK=0
+ZSV_EXTRAS=
+if test "$MINIMAL" = "no" ; then
+    ZSV_EXTRAS=1
 fi
 
 printf "creating $CONFIGFILE... "
@@ -428,25 +583,36 @@ cat << EOF
 # Any changes made here will be lost if configure is re-run
 PREFIX = $PREFIX
 EXEC_PREFIX = $EXEC_PREFIX
-BINDIR = $BINDIR
+BINDIR = $EXEC_PREFIX/bin
+LIBDIR = $EXEC_PREFIX/lib
+INCLUDEDIR = $EXEC_PREFIX/include
+
 DOCPREFIX = $DOCDIR
 MANPREFIX = $MANDIR
-SHAREPREFIX = $SHAREDIR
 CC = $CC
 AWK = $AWK
+MAKE = $MAKE
+
 AR = $AR
 RANLIB = $RANLIB
-LLVM_PROFDATA = $LLVM_PROFDATA
-PROFDATA = $PROFDATA
 CFLAGS = $CFLAGS
 LDFLAGS = $LDFLAGS
 CFLAGS_STD = $CFLAGS_STD
 LDFLAGS_STD = $LDFLAGS_STD
 CFLAGS_OPT = $CFLAGS_OPT
 LDFLAGS_OPT = $LDFLAGS_OPT
+LDFLAGS_TERMCAP = $LDFLAGS_TERMCAP
+LDFLAGS_JQ = $LDFLAGS_JQ
 CFLAGS_AUTO = $CFLAGS_AUTO
+CFLAGS_LTO = $CFLAGS_LTO
 LDFLAGS_AUTO = $LDFLAGS_AUTO
 CFLAGS_AVX2 = $CFLAGS_AVX2
+
+HAVE_AVX512=$HAVE_AVX512
+CFLAGS_AVX_512=$CFLAGS_AVX_512
+HAVE_AVX256=$HAVE_AVX256
+CFLAGS_AVX_256=$CFLAGS_AVX_256
+
 CFLAGS_CLMUL = $CFLAGS_CLMUL
 CFLAGS_DEBUG = -U_FORTIFY_SOURCE -UNDEBUG -O0 -g3 -ggdb -Wall -Wextra -Wno-missing-field-initializers -Wno-unused-parameter
 LDFLAGS_DEBUG = -U_FORTIFY_SOURCE -UNDEBUG -O0 -g3 -ggdb
@@ -456,10 +622,71 @@ CFLAGS_PIE = $CFLAGS_PIE
 LDFLAGS_PIE = $LDFLAGS_PIE
 USE_SMALL_LUT = $USE_SMALL_LUT
 USE_DEBUG_STDERR = $USE_DEBUG_STDERR
-USE_CLOCK = $USE_CLOCK
+CFLAGS_VECTORIZE = $CFLAGS_VECTORIZE
+CFLAGS_VECTORIZE_OPTIMIZED = $CFLAGS_VECTORIZE_OPTIMIZED
+CFLAGS_VECTORIZE_MISSED = $CFLAGS_VECTORIZE_MISSED
+CFLAGS_VECTORIZE_ALL = $CFLAGS_VECTORIZE_ALL
+CFLAGS_OPENMP = $CFLAGS_OPENMP
+
+ZSV_EXTRAS = $ZSV_EXTRAS
+
+$NO_HAVE
+$USE_LIBS
+
 EOF
 exec 1>&3 3>&-
 
 printf "done\n"
 
+echo ""
+echo "****************************************************************"
+echo "*  zsv configuration                                           *"
+echo "****************************************************************"
+if [ "$LDFLAGS_JQ" = "" ]; then
+    echo "*  - libjq (-ljq): no. \`jq\` command will be disabled           *"
+else
+    echo "*  - libjq: yes                                                *"
+fi
+
+if [ "$LDFLAGS_TERMCAP" = "" ]; then
+    echo "*  - termcap: no. \`pretty\` will use default width assumption   *"
+else
+    echo "*  - termcap: yes                                              *"
+fi
+
+if [ "$HAVE_AVX512" = "1" ]; then
+    echo "*  - using 512-bit AVX instruction set"
+elif [ "$HAVE_AVX256" = "1" ]; then
+    echo "*  - using 256-bit AVX instruction set"
+else
+    echo "*  - using 128-bit vector size"
+fi
+
+echo "****************************************************************"
+
+if ! [ "$MAKE" = "" ]; then
+    echo ""
+    echo "To build and install, run"
+    echo "$MAKE install" > `pwd`/install.sh 2>/dev/null && chmod 755 `pwd`/install.sh 2>/dev/null &&
+        printf "  ./install.sh\nor\n"
+    echo "  $MAKE install"
+    echo ""
+    echo "Other common commands:"
+    echo "  $MAKE                     # print available make commands"
+    echo "  (cd src && $MAKE install) # install library"
+    echo "  (cd app && $MAKE install) # install library and zsv CLI"
+    echo "  $MAKE uninstall           # uninstall library and zsv CLI"
+    echo "  $MAKE clean               # remove build artifacts"
+    echo ""
+fi
+
+if ! "$CC" --version | grep -i gcc >/dev/null && ! "$CC" --version | grep -i clang >/dev/null ; then
+    echo "*********************** WARNING!! ***********************"
+    echo "* Non-gcc/clang compiler untested; use at your own risk *"
+    echo "* consider using gcc or clang instead e.g.:             *"
+    echo "*       ./configure CC=gcc-11                           *"
+    echo "*********************************************************"
+    echo ""
+fi
+
 exit 0
diff --git a/app/ext_example/my_extension.c b/app/ext_example/my_extension.c
index f3e87c8f..a3673f5d 100644
--- a/app/ext_example/my_extension.c
+++ b/app/ext_example/my_extension.c
@@ -61,7 +61,7 @@ static struct zsv_ext_callbacks zsv_cb;
  * but with an additional preceding zsv_execution_context parameter.
  * Here, we just declare the functions; we fully define them further below
  */
-static enum zsv_ext_status count_main(zsv_execution_context ctx, int argc, const char *argv[]);
+enum zsv_ext_status count_main(zsv_execution_context ctx, int argc, const char *argv[]);
 static enum zsv_ext_status echo_main(zsv_execution_context ctx, int argc, const char *argv[]);
 
 /**
@@ -235,7 +235,7 @@ static const char *count_help =
   "usage: count [-h,--help] [filename]\n"
   ;
 
-static enum zsv_ext_status count_main(zsv_execution_context ctx, int argc, const char *argv[]) {
+enum zsv_ext_status count_main(zsv_execution_context ctx, int argc, const char *argv[]) {
   /* help */
   if(argc > 1 && (!strcmp(argv[1], "-h") || !strcmp(argv[1], "--help"))) {
     printf("%s", count_help);
diff --git a/app/ext_example/newline.csv b/app/ext_example/newline.csv
new file mode 100644
index 00000000..2b287f21
--- /dev/null
+++ b/app/ext_example/newline.csv
@@ -0,0 +1,2 @@
+"hi
+there"
\ No newline at end of file
diff --git a/app/ext_example/test/expected/zsvext-test-3.out b/app/ext_example/test/expected/zsvext-test-3.out
index c779e18c..a3e075d3 100644
--- a/app/ext_example/test/expected/zsvext-test-3.out
+++ b/app/ext_example/test/expected/zsvext-test-3.out
@@ -7,18 +7,23 @@ zsv: streaming csv processor
 
 Usage:
   zsv version: display version info (and if applicable, extension info)
-  zsv register [<extension_id>]: register an extension
+  zsv (un)register [<extension_id>]: (un)register an extension
+      Registration info is saved in zsv.ini located in a directory determined as:
+        ZSV_CONFIG_DIR environment variable value, if set
+        otherwise, /usr/local/etc
   zsv help [<command>]
-  zsv license [<extension_id>]
   zsv <command> <options> <arguments>: run a command on data (see below for details)
   zsv <id>-<cmd> <options> <arguments>: invoke command 'cmd' of extension 'id'
+  zsv thirdparty: view third-party licenses & acknowledgements
+  zsv license [<extension_id>]
 
 Options common to all commands:
-  -c,--max-column-count: set the maximum number of columns parsed per row. defaults to 1024
-  -r,--max-row-size: set the minimum supported maximum row size. defaults to 128k
-  -B,--buff-size: set internal buffer size. defaults to 256k
+  -L,--limit-rows <n>: limit processing to the given number of rows (including any header row(s))
+  -c,--max-column-count <n>: set the maximum number of columns parsed per row. defaults to 1024
+  -r,--max-row-size <n>: set the minimum supported maximum row size. defaults to 64k
+  -B,--buff-size <n>: set internal buffer size. defaults to 256k
   -t,--tab-delim: set column delimiter to tab
-  -O,--other-delim: set column delimiter to other column
+  -O,--other-delim <char>: set column delimiter to specified character
   -q,--no-quote: turn off quote handling
   -v,--verbose: verbose output
 
@@ -30,10 +35,12 @@ Commands:
   pretty: pretty print for console display
   flatten: flatten a table consisting of N groups of data, each with 1 or
            more rows in the table, into a table of N rows
-  2json: convert to json
+  2json: convert CSV or sqlite3 db table to json
+  2db:   convert json to sqlite3 db
   2tsv : convert to tab-delimited text
   serialize: convert into 3-column format (id, column name, cell value)
   stack: stack tables vertically, aligning columns with common names
+  jq:    run a jq filter on json input
 
 (No extended commands)
 Extension my registered
@@ -43,18 +50,23 @@ zsv: streaming csv processor
 
 Usage:
   zsv version: display version info (and if applicable, extension info)
-  zsv register [<extension_id>]: register an extension
+  zsv (un)register [<extension_id>]: (un)register an extension
+      Registration info is saved in zsv.ini located in a directory determined as:
+        ZSV_CONFIG_DIR environment variable value, if set
+        otherwise, /usr/local/etc
   zsv help [<command>]
-  zsv license [<extension_id>]
   zsv <command> <options> <arguments>: run a command on data (see below for details)
   zsv <id>-<cmd> <options> <arguments>: invoke command 'cmd' of extension 'id'
+  zsv thirdparty: view third-party licenses & acknowledgements
+  zsv license [<extension_id>]
 
 Options common to all commands:
-  -c,--max-column-count: set the maximum number of columns parsed per row. defaults to 1024
-  -r,--max-row-size: set the minimum supported maximum row size. defaults to 128k
-  -B,--buff-size: set internal buffer size. defaults to 256k
+  -L,--limit-rows <n>: limit processing to the given number of rows (including any header row(s))
+  -c,--max-column-count <n>: set the maximum number of columns parsed per row. defaults to 1024
+  -r,--max-row-size <n>: set the minimum supported maximum row size. defaults to 64k
+  -B,--buff-size <n>: set internal buffer size. defaults to 256k
   -t,--tab-delim: set column delimiter to tab
-  -O,--other-delim: set column delimiter to other column
+  -O,--other-delim <char>: set column delimiter to specified character
   -q,--no-quote: turn off quote handling
   -v,--verbose: verbose output
 
@@ -66,10 +78,12 @@ Commands:
   pretty: pretty print for console display
   flatten: flatten a table consisting of N groups of data, each with 1 or
            more rows in the table, into a table of N rows
-  2json: convert to json
+  2json: convert CSV or sqlite3 db table to json
+  2db:   convert json to sqlite3 db
   2tsv : convert to tab-delimited text
   serialize: convert into 3-column format (id, column name, cell value)
   stack: stack tables vertically, aligning columns with common names
+  jq:    run a jq filter on json input
 
 Extended commands:
   Extension 'my': Sample zsv extension
diff --git a/app/ext_example/test/expected/zsvext-test-4.out b/app/ext_example/test/expected/zsvext-test-4.out
index a6a5f2db..3e91379d 100644
--- a/app/ext_example/test/expected/zsvext-test-4.out
+++ b/app/ext_example/test/expected/zsvext-test-4.out
@@ -1,7 +1,7 @@
 
-==========================
+====================================================
 ZSV/lib license 
-==========================
+====================================================
 Permission is hereby granted, free of charge, to any person obtaining a copy of
 this software and associated documentation files (the "Software"), to deal in
 the Software without restriction, including without limitation the rights to
@@ -20,9 +20,9 @@ LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 SOFTWARE.
 
-==========================
+====================================================
 ZSV/lib license 
-==========================
+====================================================
 Permission is hereby granted, free of charge, to any person obtaining a copy of
 this software and associated documentation files (the "Software"), to deal in
 the Software without restriction, including without limitation the rights to
@@ -41,7 +41,7 @@ LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 SOFTWARE.
 
-==========================
+====================================================
 License for extension 'my'
-==========================
+====================================================
 Unlicense. See https://github.com/spdx/license-list-data/blob/master/text/Unlicense.txt
diff --git a/app/ext_example/test/expected/zsvext-test-5.out b/app/ext_example/test/expected/zsvext-test-5.out
new file mode 100644
index 00000000..8f9ca4d6
--- /dev/null
+++ b/app/ext_example/test/expected/zsvext-test-5.out
@@ -0,0 +1,2 @@
+Rows: 0
+Rows: 1
diff --git a/app/ext_example/test/expected/zsvext-test-thirdparty.out b/app/ext_example/test/expected/zsvext-test-thirdparty.out
index 6815a818..89b35a18 100644
--- a/app/ext_example/test/expected/zsvext-test-thirdparty.out
+++ b/app/ext_example/test/expected/zsvext-test-thirdparty.out
@@ -1,13 +1,13 @@
 Third-party licenses and acknowldgements
 
 ==========================
-ZSV/lib
+ZSV/lib third-party dependencies
 ==========================
 See https://github.com/liquidaty/zsv/blob/main/misc/THIRDPARTY.md
 Third-party licenses and acknowldgements
 
 ==========================
-ZSV/lib
+ZSV/lib third-party dependencies
 ==========================
 See https://github.com/liquidaty/zsv/blob/main/misc/THIRDPARTY.md
 
diff --git a/app/utils/dirs.c b/app/utils/dirs.c
index b0a13be2..2957e9de 100644
--- a/app/utils/dirs.c
+++ b/app/utils/dirs.c
@@ -37,15 +37,23 @@ static size_t chop_slash(char* buff, size_t len) {
  */
 size_t get_config_dir(char* buff, size_t buffsize, const char *prefix) {
 #if defined(_WIN32)
-  const char *env = prefix;
-  const char *env_val = getenv(env);
+  const char *env_val = getenv("ZSV_CONFIG_DIR");
+  //  if(!(env_val && *env_val))
+  //    env_val = getenv(prefix);
   if(!(env_val && *env_val))
     env_val = getenv("LOCALAPPDATA");
+  if(!(env_val && *env_val))
+    env_val = "C:\\temp";
   int written = snprintf(buff, buffsize, "%s", env_val);
 #elif defined(__EMSCRIPTEN__)
   int written = snprintf(buff, buffsize, "/tmp");
 #else
-  int written = snprintf(buff, buffsize, "%s/etc", prefix ? prefix : "");
+  int written;
+  const char *env_val = getenv("ZSV_CONFIG_DIR");
+  if(env_val && *env_val)
+    written = snprintf(buff, buffsize, "%s", env_val);
+  else
+    written = snprintf(buff, buffsize, "%s/etc", prefix ? prefix : "");
 #endif
   if(written > 0 && ((size_t)written) < buffsize)
     return chop_slash(buff, written);
diff --git a/scripts/ci-build.sh b/scripts/ci-build.sh
index ea14d8b6..d2977f96 100755
--- a/scripts/ci-build.sh
+++ b/scripts/ci-build.sh
@@ -53,10 +53,14 @@ if [ "$RUN_TESTS" = true ]; then
   rm -rf build "$PREFIX"
   "$MAKE" test
   echo "[INF] Tests completed successfully!"
+
+  echo "[INF] Configuring example extension and running example extension tests"
+  (cd app/ext_example && "$MAKE" CONFIGFILE=../../config.mk test)
+  echo "[INF] Tests completed successfully!"
 fi
 
 echo "[INF] Building"
-rm -rf build "$PREFIX"
+rm -rf build "$PREFIX" /usr/local/etc/zsv.ini
 "$MAKE" install
 tree -h "$PREFIX"
 echo "[INF] Built successfully!"
diff --git a/src/vector_delim.c b/src/vector_delim.c
index f1fc6402..9b8d9a48 100644
--- a/src/vector_delim.c
+++ b/src/vector_delim.c
@@ -45,7 +45,6 @@ static inline int vec_delims(const unsigned char *s, size_t n,
   unsigned total_bytes = 0;
 
   for(unsigned i = 0; i < j; i++) {
-    // memcpy(&str_simd, pSrc1 + i, VECTOR_BYTES); -- will bus error on clang+BSD
     memcpy(&str_simd, s + i*sizeof(str_simd), sizeof(str_simd));
     zsv_uc_vector vtmp = str_simd == *char_match1;
     vtmp += (str_simd == *char_match2);
diff --git a/src/zsv_internal.c b/src/zsv_internal.c
index 53de2f25..ea074d77 100644
--- a/src/zsv_internal.c
+++ b/src/zsv_internal.c
@@ -158,7 +158,7 @@ __attribute__((always_inline)) static inline enum zsv_status row_dl(struct zsv_s
             scanner->row.allocated + scanner->row.overflow, scanner->row.allocated);
     scanner->row.overflow = 0;
   }
-  if(scanner->opts.row)
+  if(LIKELY(scanner->opts.row))
     scanner->opts.row(scanner->opts.ctx);
 # ifdef ZSV_EXTRAS
   scanner->progress.cum_row_count++;
@@ -198,8 +198,8 @@ __attribute__((always_inline)) static inline enum zsv_status row_dl(struct zsv_s
   if(VERY_UNLIKELY(scanner->abort))
     return zsv_status_cancelled;
   scanner->have_cell = 0;
-  if(scanner->row.used)
-    scanner->row.used = 0;
+//  if(scanner->row.used)
+  scanner->row.used = 0;
   return zsv_status_ok;
 }
 
@@ -208,20 +208,29 @@ static inline enum zsv_status cell_and_row_dl(struct zsv_scanner *scanner, unsig
   return row_dl(scanner);
 }
 
-#if defined(HAVE_AVX512)
-# define VECTOR_BYTES 64
-# define VECTOR_SIZE 512
-# define zsv_mask_t uint64_t
-# define movemask_pseudo(x) _mm512_movepi8_mask((__m512i)x)
-# define NEXT_BIT __builtin_ffsl
-#elif defined(HAVE_AVX256)
-# define VECTOR_BYTES 32
-# define VECTOR_SIZE 256
-# define zsv_mask_t uint32_t
-# define movemask_pseudo(x) _mm256_movemask_epi8((__m256i)x)
-# define NEXT_BIT __builtin_ffs
-#else
-# define ZSV_NO_AVX
+#ifndef ZSV_NO_AVX
+# if !defined(__AVX2__)
+#  define ZSV_NO_AVX
+# elif defined(HAVE_AVX512)
+#  ifndef __AVX512BW__
+#   error AVX512 requested, but __AVX512BW__ macro not defined
+#  else
+#   define VECTOR_BYTES 64
+#   define zsv_mask_t uint64_t
+#   define movemask_pseudo(x) _mm512_movepi8_mask((__m512i)x)
+#   define NEXT_BIT __builtin_ffsl
+#  endif
+# elif defined(HAVE_AVX256)
+#  define VECTOR_BYTES 32
+#  define zsv_mask_t uint32_t
+#  define movemask_pseudo(x) _mm256_movemask_epi8((__m256i)x)
+#  define NEXT_BIT __builtin_ffs
+# else
+#  define ZSV_NO_AVX
+# endif
+#endif // ndef ZSV_NO_AVX
+
+#if defined(ZSV_NO_AVX)
 # define zsv_mask_t uint16_t
 # define VECTOR_BYTES 16
 # define NEXT_BIT __builtin_ffs
@@ -258,7 +267,7 @@ static inline zsv_mask_t movemask_pseudo(zsv_uc_vector v) {
   vst1q_lane_u8((uint8_t*)&mask + 1, (uint8x16_t)imask, 8);
   return mask;
 #else
-
+  // to do: see https://github.com/WebAssembly/simd/issues/131 for wasm
   zsv_mask_t mask = 0, tmp = 1;
   for(size_t i = 0; i < sizeof(zsv_uc_vector); i++) {
     mask += (v[i] ? tmp : 0);
@@ -285,16 +294,18 @@ static enum zsv_status zsv_scan_delim(struct zsv_scanner *scanner,
 
   scanner->partial_row_length = 0;
 
-  int quote = '"'; // ascii code 34
+  int quote = scanner->opts.no_quotes > 0 ? -1 : '"'; // ascii code 34
   zsv_uc_vector dl_v; memset(&dl_v, delimiter, sizeof(zsv_uc_vector)); // ascii 44
   zsv_uc_vector nl_v; memset(&nl_v, '\n', sizeof(zsv_uc_vector)); // ascii code 10
   zsv_uc_vector cr_v; memset(&cr_v, '\r', sizeof(zsv_uc_vector)); // ascii code 13
-  zsv_uc_vector qt_v;
+  zsv_uc_vector qt_v; memset(&qt_v, scanner->opts.no_quotes > 0 ? 0 : '"', sizeof(qt_v));
+  /*
   if(scanner->opts.no_quotes > 0) {
     quote = -1;
     memset(&qt_v, 0, sizeof(qt_v));
   } else
     memset(&qt_v, '"', sizeof(zsv_uc_vector));
+  */
 
   // case "hel"|"o": check if we have an embedded dbl-quote past the initial opening quote, which was
   // split between the last buffer and this one e.g. "hel""o" where the last buffer ended
@@ -320,7 +331,7 @@ static enum zsv_status zsv_scan_delim(struct zsv_scanner *scanner,
 
   scanner->buffer_end = bytes_read;
   for(; i < bytes_read; i++) {
-    if(mask == 0) {
+    if(UNLIKELY(mask == 0)) {
       mask_last_start = i;
       if(VERY_LIKELY(i < bytes_chunk_end)) {
         // keep going until we get a delim or we are at the eof
@@ -340,7 +351,7 @@ static enum zsv_status zsv_scan_delim(struct zsv_scanner *scanner,
       size_t next_offset = NEXT_BIT(mask);
       i = mask_last_start + next_offset - 1;
       mask = clear_lowest_bit(mask);
-      if(skip_next_delim) {
+      if(VERY_UNLIKELY(skip_next_delim)) {
         skip_next_delim = 0;
         continue;
       }