diff --git a/Makefile b/Makefile
index e4e398d..fda2356 100644
--- a/Makefile
+++ b/Makefile
@@ -45,12 +45,15 @@ check-api: assert-SCRIPT_CALL assert-bats
 
 ## FIXME: How do I use node/npm so it finds the 'seguid' module?
 check-api/seguid-javascript:
-	$(MAKE) check-api SCRIPT_CALL="node" SCRIPT_PREAMBLE="const { seguid, lsseguid, ldseguid, csseguid, cdseguid } = require('seguid')" SCRIPT_PRINT_FMT="console.log(%s)"
+	$(MAKE) check-api SCRIPT_CALL="node" SCRIPT_PREAMBLE="const { seguid, lsseguid, ldseguid, csseguid, cdseguid } = require('seguid')" SCRIPT_PRINT_FMT="console.log(%s)" SCRIPT_ARGS_SEP=", "
 
 check-api/seguid-python:
-	$(MAKE) check-api SCRIPT_CALL="python" SCRIPT_PREAMBLE="from seguid import *" SCRIPT_PRINT_FMT="out=%s\nif isinstance(out, tuple):\n     out=' '.join(out)\nprint(out)"
+	$(MAKE) check-api SCRIPT_CALL="python" SCRIPT_PREAMBLE="from seguid import *" SCRIPT_PRINT_FMT="out=%s\nif isinstance(out, tuple):\n     out=' '.join(out)\nprint(out)" SCRIPT_ARGS_SEP=", "
 
 check-api/seguid-r:
-	$(MAKE) check-api SCRIPT_CALL="Rscript --no-init-file" SCRIPT_PREAMBLE="library(seguid)" SCRIPT_PRINT_FMT="cat(%s)"
+	$(MAKE) check-api SCRIPT_CALL="Rscript --no-init-file" SCRIPT_PREAMBLE="library(seguid)" SCRIPT_PRINT_FMT="cat(%s)" SCRIPT_ARGS_SEP=", "
+
+check-api/seguid-tcl:
+	$(MAKE) check-api SCRIPT_CALL="tclsh" SCRIPT_PREAMBLE="source ../src/base64.tcl; source ../src/sha1.tcl; source ../src/seguid.tcl;" SCRIPT_PRINT_FMT="puts stdout [%s]" SCRIPT_ARGS_SEP=" " SCRIPT_CALL_FMT="%s %s"
 
 check-api/ALL: check-api/seguid-python check-api/seguid-r
diff --git a/tests-api/utils.sh b/tests-api/utils.sh
index 6dd9a50..ee04ebc 100644
--- a/tests-api/utils.sh
+++ b/tests-api/utils.sh
@@ -10,8 +10,14 @@ setup_api_test() {
   script_print_fmt="${SCRIPT_PRINT_FMT:-print(%s)}"
   echo "script_print_fmt: ${script_print_fmt}"
 
-  script_args_sep="${SCRIPT_ARGS_SEP:-, }"
-  echo "script_args_sep: ${script_args_sep}"
+  script_args_sep="${SCRIPT_ARGS_SEP}"
+  if [[ -z ${script_args_sep} ]]; then
+      script_args_sep=" "
+  fi
+  echo "script_args_sep: '${script_args_sep}'"
+
+  script_call_fmt="${SCRIPT_CALL_FMT:-%s(%s)}"
+  echo "script_call_fmt: ${script_call_fmt}"
 }
 
 
@@ -48,7 +54,7 @@ api_call() {
   ## Add script preamble
   printf "%s\n" "${script_preamble[@]}" > "${tf}"
   ## Generate API call
-  call="${fcn}($(args_to_string "${args[@]}"))"
+  call=$(printf "${script_call_fmt}" "${fcn}" "$(args_to_string "${args[@]}")")
   ## Wrap API call in print statement
   call=$(printf "${script_print_fmt}" "${call}")
   printf "%s\n" "${call}" >> "${tf}"