diff --git a/.envrc b/.envrc
new file mode 100644
index 0000000..3550a30
--- /dev/null
+++ b/.envrc
@@ -0,0 +1 @@
+use flake
diff --git a/.gitignore b/.gitignore
index e342029..c7e883b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -7,3 +7,4 @@ target/
 
 data_*_flex.json
 data_*_haveranswer.f64
+.direnv/