diff --git a/.bazelversion b/.bazelversion
index ee74734..7c69a55 100644
--- a/.bazelversion
+++ b/.bazelversion
@@ -1 +1 @@
-4.1.0
+3.7.0
diff --git a/.envrc b/.envrc
new file mode 100644
index 0000000..fa466bb
--- /dev/null
+++ b/.envrc
@@ -0,0 +1,8 @@
+export PATH="$(git rev-parse --show-toplevel)/bin:$PATH"
+
+if [[ ! -x bin/bazel ]]; then
+    mkdir -p bin
+    wget https://github.com/bazelbuild/bazelisk/releases/download/v1.9.0/bazelisk-linux-amd64 \
+        -O bin/bazel
+    chmod a+x bin/bazel
+fi
diff --git a/.gitignore b/.gitignore
index bc03aa4..0f810e9 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,7 +1,8 @@
 *~
 *.sw[op]
 
-/bazel
+/bin/bazel
+
 /bazel-bazel-zig-cc
 /bazel-bin
 /bazel-out
diff --git a/toolchain/BUILD.sdk.bazel b/toolchain/BUILD.sdk.bazel
index c376152..fc65b78 100644
--- a/toolchain/BUILD.sdk.bazel
+++ b/toolchain/BUILD.sdk.bazel
@@ -4,7 +4,8 @@ package(
     default_visibility = ["//visibility:public"],
 )
 
+# TODO(motiejus) use json.encode() and unquote these variables with bazel 4+.
 zig_build_macro(
-    absolute_path = {absolute_path},
-    zig_include_root = {zig_include_root},
+    absolute_path = "{absolute_path}",
+    zig_include_root = "{zig_include_root}",
 )
diff --git a/toolchain/defs.bzl b/toolchain/defs.bzl
index 9e290e3..67aedc0 100644
--- a/toolchain/defs.bzl
+++ b/toolchain/defs.bzl
@@ -157,14 +157,13 @@ def _zig_repository_impl(repository_ctx):
             ZIG_TOOL_WRAPPER.format(zig = str(repository_ctx.path("zig")), zig_tool = zig_tool),
         )
 
-    absolute_path = json.encode(str(repository_ctx.path("")))
     repository_ctx.template(
         "BUILD.bazel",
         Label("//toolchain:BUILD.sdk.bazel"),
         executable = False,
         substitutions = {
-            "{absolute_path}": absolute_path,
-            "{zig_include_root}": json.encode(zig_include_root),
+            "{absolute_path}": str(repository_ctx.path("")),
+            "{zig_include_root}": zig_include_root,
         },
     )