diff --git a/.gitignore b/.gitignore
index 627929b..f65d8f6 100644
--- a/.gitignore
+++ b/.gitignore
@@ -10,3 +10,4 @@ prof.json
 *.cpuprofile
 *.cpuprofile.gz
 *v8.log*
+callgrind.out.*
diff --git a/Justfile b/Justfile
index afc96a7..b6bba19 100644
--- a/Justfile
+++ b/Justfile
@@ -29,3 +29,8 @@
 [no-exit-message]
 @evalp expr:
   cargo run --release --features prof -- eval --expr '{{expr}}'
+
+[no-exit-message]
+[positional-arguments]
+@cg *args='':
+  valgrind --tool=callgrind --dump-instr=yes --collect-jumps=yes "$@"