diff --git a/Justfile b/Justfile
index 03e803761..1159084da 100644
--- a/Justfile
+++ b/Justfile
@@ -482,13 +482,23 @@ SHELLTEST := STACK + ' exec -- shelltest --execdir --exclude=/_ --threads=32'
 
 #  --hide-successes
 
-# build hledger warning-free and run functional tests, with any shelltest OPTS (requires mktestaddons)
+# build hledger warning-free and run functional tests, with any shelltest OPTS. (after mktestaddons)
 @functest *STOPTS:
     $STACK build --ghc-options=-Werror hledger
     time (({{ SHELLTEST }} --hide {{ if STOPTS == '' { '' } else { STOPTS } }} \
         hledger/test/ bin/ \
+        -x hledger/test/perf.test \
         -x ledger-compat/ledger-baseline -x ledger-compat/ledger-regress -x ledger-compat/ledger-extra \
         && echo $@ PASSED) || (echo $@ FAILED; false))
+# too fragile
+#    echo
+#    just perftest {{ STOPTS }}
+
+# run performance tests with the hledger in PATH, logging to perf.log and expecting a certain txns/s. Accepts shelltest OPTS.
+@perftest *STOPTS:
+    echo "Running performance tests..."
+    time (({{ SHELLTEST }} --hide {{ if STOPTS == '' { '' } else { STOPTS } }} hledger/test/perf.test \
+        && echo $@ PASSED) || (echo $@ FAILED; false))
 
 ADDONEXTS := 'pl py rb sh hs lhs rkt exe com bat'
 ADDONSDIR := 'hledger/test/cli/addons'
diff --git a/hledger/test/perf.test b/hledger/test/perf.test
new file mode 100644
index 000000000..12c6f3cdb
--- /dev/null
+++ b/hledger/test/perf.test
@@ -0,0 +1,12 @@
+# * performance tests
+# This file is run after the other functional tests have completed,
+# so that they don't slow it down.
+
+# ** 1. Log performance stats to a persistent perf.log.
+# so that we can detect changes over time.
+# Ideally we would detect regressions and fail automatically,
+# but it's hard to ensure consistent machine performance.
+$ hledger stats -1 -f ../../examples/10ktxns-1kaccts.journal >>../../perf.log
+
+# ** 2. Test that it hits at least 14k txns/s within a few runs.
+$ hledger stats -1 -f ../../examples/10ktxns-1kaccts.journal >>../../perf.log; hledger stats -1 -f ../../examples/10ktxns-1kaccts.journal >>../../perf.log; hledger stats -1 -f ../../examples/10ktxns-1kaccts.journal >>../../perf.log; tail -3 ../../perf.log | grep -qE '[1-9][4-9]... txns/s'