Fix playground build

Author: cknitt

packages/playground/rollup.config.mjs

@@ -3,7 +3,7 @@ import nodeResolve from "@rollup/plugin-node-resolve";
 import { glob } from "glob";
 
 const RESCRIPT_COMPILER_ROOT_DIR = path.join(import.meta.dirname, "..", "..");
-const LIB_DIR = path.join(RESCRIPT_COMPILER_ROOT_DIR, "lib");
+const LIB_DIR = path.join(RESCRIPT_COMPILER_ROOT_DIR, "packages", "@rescript", "runtime", "lib");
 
 // Final target output directory where all the cmijs will be stored
 const PACKAGES_DIR = path.join(import.meta.dirname, "packages");

packages/playground/scripts/generate_cmijs.mjs

@@ -28,7 +28,7 @@ exec("yarn rescript legacy");
 
 // We need to build the compiler's builtin modules as a separate cmij.
 // Otherwise we can't use them for compilation within the playground.
-buildCmij(compilerRootDir, "compiler-builtins");
+buildCmij(path.join(compilerRootDir, "packages", "@rescript", "runtime"), "compiler-builtins");
 
 const packages = resConfig["dependencies"];
 for (const pkgName of packages) {