slackbuilds.org po4a fails to build

trying to build the po4a package from slackbuilds.org (to be used with kicad-docs.) this looks like it is missing a dependency, kpsewhich, that i'm not able to identify. if it's on slackbuilds, i can't determine the package.

does anyone have a suggestion?

thanks.

Code:t/14-porefs.t ......... ok
t/15-rubydoc.t ........ ok
t/16-sgml.t ........... ok
t/17-splitted.t ....... ok
t/18-texinfo.t ........ ok
--- t-19-tex/simple.err 2018-12-09 10:27:11.000000000 -0600
+++ tmp/simple.err 2020-11-01 11:26:34.597719229 -0600
@@ -1 +1,3 @@
+Can't exec "kpsewhich": No such file or directory at /home/proj/slackware/kicadbld/po4a/SBo/po4a-0.55/blib/lib/Locale/Po4a/TeX.pm line 1017.
+readline() on closed filehandle KPSEA at /home/proj/slackware/kicadbld/po4a/SBo/po4a-0.55/blib/lib/Locale/Po4a/TeX.pm line 1018.
po4a::tex: kpsewhich cannot find article-wrong.cls

# Failed test 'gettextize well a simple tex document returns what is expected'
# at t/Testhelper.pm line 122.
# got: '256'
# expected: '0'
# Failed (retval=256) on:
# perl compare-po.pl t-19-tex/simple.pot tmp/simple.pot && diff -u t-19-tex/simple.out tmp/simple.out 1>&2 && diff -u t-19-tex/simple.err tmp/simple.err 1>&2 && diff -u t-19-tex/simple.trans.out tmp/simple.trans.out 1>&2 && diff -u t-19-tex/simple.trans.err tmp/simple.trans.err 1>&2
# Was created with:
# perl ../po4a-normalize -f latex t-19-tex/simple.tex > tmp/simple.err 2>&1 && mv po4a-normalize.po tmp/simple.pot && mv po4a-normalize.output tmp/simple.out && perl ../po4a-translate -f latex -m t-19-tex/simple.tex -p t-19-tex/simple.trans.po -l tmp/simple.trans.out > tmp/simple.trans.err 2>&1
--- t-19-tex/simple-updatepo.out 2018-12-09 10:27:11.000000000 -0600
+++ tmp/simple-updatepo.out 2020-11-01 11:26:34.782719219 -0600
@@ -1,2 +1,4 @@
+Can't exec "kpsewhich": No such file or directory at /home/proj/slackware/kicadbld/po4a/SBo/po4a-0.55/blib/lib/Locale/Po4a/TeX.pm line 1017.
+readline() on closed filehandle KPSEA at /home/proj/slackware/kicadbld/po4a/SBo/po4a-0.55/blib/lib/Locale/Po4a/TeX.pm line 1018.
po4a::tex: kpsewhich cannot find article-wrong.cls
-. done.
+.. done.

# Failed test 'updatepo for this document returns what is expected'
# at t/Testhelper.pm line 122.
# got: '256'
# expected: '0'
# Failed (retval=256) on:
# diff -u -I '^.* done.' t-19-tex/simple-updatepo.out tmp/simple-updatepo.out 1>&2&& perl compare-po.pl t-19-tex/simple.trans.po tmp/simple.trans.po
# Was created with:
# cp t-19-tex/simple.trans.po tmp && chmod u+w tmp/simple.trans.po && perl ../po4a-updatepo -f latex -m t-19-tex/simple.tex -p tmp/simple.trans.po > tmp/simple-updatepo.out 2>&1
--- t-19-tex/theorem.err 2018-12-09 10:27:11.000000000 -0600
+++ tmp/theorem.err 2020-11-01 11:26:34.867719215 -0600
@@ -0,0 +1,3 @@
+Can't exec "kpsewhich": No such file or directory at /home/proj/slackware/kicadbld/po4a/SBo/po4a-0.55/blib/lib/Locale/Po4a/TeX.pm line 1017.
+readline() on closed filehandle KPSEA at /home/proj/slackware/kicadbld/po4a/SBo/po4a-0.55/blib/lib/Locale/Po4a/TeX.pm line 1018.
+po4a::tex: kpsewhich cannot find article.cls

# Failed test 'gettextize well a LaTeX document with theorem environments returns what is expected'
# at t/Testhelper.pm line 122.
# got: '256'
# expected: '0'
# Failed (retval=256) on:
# perl compare-po.pl t-19-tex/theorem.pot tmp/theorem.pot && diff -u t-19-tex/theorem.out tmp/theorem.out 1>&2 && diff -u t-19-tex/theorem.err tmp/theorem.err 1>&2
# Was created with:
# perl ../po4a-normalize -f latex t-19-tex/theorem.tex > tmp/theorem.err 2>&1 && mv po4a-normalize.po tmp/theorem.pot && mv po4a-normalize.output tmp/theorem.out
# Looks like you failed 3 tests of 6.
t/19-tex.t ............
Dubious, test returned 3 (wstat 768, 0x300)
Failed 3/6 subtests
t/20-text.t ........... ok
t/21-TransTractors.t .. ok
t/22-wml.t ............ ok
t/23-xhtml.t .......... ok
t/24-xml.t ............ ok
t/25-yaml.t ........... ok

Test Summary Report
-------------------
t/12-msguntypot.t (Wstat: 0 Tests: 16 Failed: 0)
TODO passed: 5
t/19-tex.t (Wstat: 768 Tests: 6 Failed: 3)
Failed tests: 2, 4, 6
Non-zero exit status: 3
t/20-text.t (Wstat: 0 Tests: 22 Failed: 0)
TODO passed: 19
Files=24, Tests=423, 19 wallclock secs ( 0.12 usr 0.04 sys + 14.23 cusr 2.28 csys = 16.67 CPU)
Result: FAIL
Failed 1/24 test programs. 3/423 subtests failed.