diff --git a/scripts/prepare.ts b/scripts/prepare.ts
index 014f4c3b2..69bc51eb6 100644
--- a/scripts/prepare.ts
+++ b/scripts/prepare.ts
@@ -60,7 +60,7 @@ import { consoleLogger } from '../src/logger';
             console.log('Processing ' + p.path + r);
             let c: FuncCompilationResult;
             try {
-                let stdlibPath = path.resolve(__dirname, '../src/stdlib/stdlib.fc');
+                let stdlibPath = path.resolve(__dirname, '..', 'stdlib', 'stdlib.fc');
                 let stdlib = fs.readFileSync(stdlibPath, 'utf-8');
                 let code = fs.readFileSync(p.path + r, 'utf-8');
                 c = await funcCompile({
@@ -78,6 +78,7 @@ import { consoleLogger } from '../src/logger';
                     continue;
                 }
             } catch (e) {
+                console.warn(e);
                 console.warn('Failed');
                 continue;
             }
diff --git a/src/node.ts b/src/node.ts
index d2f25cbce..465f2d1f6 100644
--- a/src/node.ts
+++ b/src/node.ts
@@ -46,7 +46,7 @@ export async function run(args: { configPath: string, projectNames?: string[] })
     // Compile 
     let success = true;
     let project = createNodeFileSystem(rootPath, false);
-    let stdlib = path.resolve(__dirname, '..', 'stdlib') + path.sep; // Improves developer experience
+    let stdlib = createNodeFileSystem(path.resolve(__dirname, '..', 'stdlib'), false); // Improves developer experience
     for (let config of projects) {
         console.log('💼 Compiling project ' + config.name + '...');
         let built = await build({ config, project, stdlib, logger: consoleLogger });
diff --git a/src/pipeline/build.ts b/src/pipeline/build.ts
index 7e69f0c92..08d9c2c23 100644
--- a/src/pipeline/build.ts
+++ b/src/pipeline/build.ts
@@ -23,12 +23,12 @@ const version = require('../../package.json').version;
 export async function build(args: {
     config: ConfigProject,
     project: VirtualFileSystem,
-    stdlib: string,
+    stdlib: string | VirtualFileSystem,
     logger?: TactLogger | null | undefined
 }) {
 
     const { config, project } = args;
-    const stdlib = createVirtualFileSystem(args.stdlib, files);
+    const stdlib = (typeof args.stdlib === 'string') ? createVirtualFileSystem(args.stdlib, files) : args.stdlib;
     const logger: TactLogger = args.logger || consoleLogger;
 
     // Configure context
diff --git a/src/vfs/createVirtualFileSystem.ts b/src/vfs/createVirtualFileSystem.ts
index e6c57dd4d..eba86deeb 100644
--- a/src/vfs/createVirtualFileSystem.ts
+++ b/src/vfs/createVirtualFileSystem.ts
@@ -3,6 +3,9 @@ import { VirtualFileSystem } from "./VirtualFileSystem";
 
 export function createVirtualFileSystem(root: string, fs: { [key: string]: string }, readonly: boolean = true): VirtualFileSystem {
     let normalizedRoot = normalize(root);
+    if (!normalizedRoot.endsWith('/')) {
+        normalizedRoot += '/';
+    }
     return {
         root: normalizedRoot,
         exists(filePath: string): boolean {