diff --git a/packages/docgen/src/compiler.ts b/packages/docgen/src/compiler.ts
index 61837ad1f8..74ba1db974 100644
--- a/packages/docgen/src/compiler.ts
+++ b/packages/docgen/src/compiler.ts
@@ -43,14 +43,14 @@ function loadOptions(path: string): ts.CompilerOptions {
 
 async function main() {
   const rootDir = resolve(__dirname, '..');
-  const srcDir = resolve(rootDir, 'src');
-  const entrypoint = resolve(srcDir, 'index.js');
-  const apiRefsDir = resolve(rootDir, 'docgen', 'build', 'api-refs');
+  const srcDir = resolve(rootDir, '..', 'core-api', 'src');
+  const entrypoint = resolve(srcDir, 'index.ts');
+  const apiRefsDir = resolve(rootDir, 'dist');
   const mkdocsYaml = resolve(apiRefsDir, 'mkdocs.yml');
 
   process.chdir(rootDir);
 
-  const options = loadOptions('../tsconfig.json');
+  const options = loadOptions('../../../tsconfig.json');
 
   delete options.moduleResolution;
   options.removeComments = false;
@@ -60,11 +60,12 @@ async function main() {
 
   const typeLocator = TypeLocator.fromProgram(program);
 
-  const { apis } = typeLocator.findExportedInstances({
-    apis: typeLocator.getExportedType(
-      resolve(srcDir, 'core', 'api', 'ApiRef.ts'),
-    ),
-  });
+  const { apis } = typeLocator.findExportedInstances(
+    {
+      apis: typeLocator.getExportedType(entrypoint, 'createApiRef'),
+    },
+    [srcDir],
+  );
 
   const apiDocGenerator = ApiDocGenerator.fromProgram(program, rootDir, srcDir);
 
diff --git a/packages/docgen/src/docgen/TypeLocator.ts b/packages/docgen/src/docgen/TypeLocator.ts
index b960640559..038a01d35e 100644
--- a/packages/docgen/src/docgen/TypeLocator.ts
+++ b/packages/docgen/src/docgen/TypeLocator.ts
@@ -54,6 +54,7 @@ export default class TypeLocator {
 
   findExportedInstances<T extends string>(
     typeLookupTable: { [key in T]: ts.Type },
+    roots: string[],
   ): { [key in T]: ExportedInstance[] } {
     const docMap = new Map<ts.Type, ExportedInstance[]>();
     for (const type of Object.values<ts.Type>(typeLookupTable)) {
@@ -61,6 +62,10 @@ export default class TypeLocator {
     }
 
     this.program.getSourceFiles().forEach(source => {
+      const inRoot = roots.some(root => source.fileName.startsWith(root));
+      if (!inRoot) {
+        return;
+      }
       ts.forEachChild(source, node => {
         const decl = this.getExportedConstructorDeclaration(node);
         if (!decl || !docMap.has(decl.constructorType)) {