diff --git a/src/puter-js/src/modules/FileSystem/index.js b/src/puter-js/src/modules/FileSystem/index.js
index 300c2b7fbb..b7f987416e 100644
--- a/src/puter-js/src/modules/FileSystem/index.js
+++ b/src/puter-js/src/modules/FileSystem/index.js
@@ -9,6 +9,7 @@ import upload from "./operations/upload.js";
 import read from "./operations/read.js";
 import move from "./operations/move.js";
 import write from "./operations/write.js";
+import share from "./operations/share.js";
 import sign from "./operations/sign.js";
 import symlink from './operations/symlink.js';
 // Why is this called deleteFSEntry instead of just delete? because delete is 
@@ -34,6 +35,7 @@ export class PuterJSFileSystemModule extends AdvancedBase {
     sign = sign;
     symlink = symlink;
     getReadURL = getReadURL;
+    share = share;
 
     FSItem = FSItem
 
diff --git a/src/puter-js/src/modules/FileSystem/operations/share.js b/src/puter-js/src/modules/FileSystem/operations/share.js
new file mode 100644
index 0000000000..d031274fba
--- /dev/null
+++ b/src/puter-js/src/modules/FileSystem/operations/share.js
@@ -0,0 +1,59 @@
+import getAbsolutePathForApp from '../utils/getAbsolutePathForApp.js';
+
+const share = async function (targetPath, options = {}) {
+    // targetPath is required
+    if (!targetPath) {
+        throw new Error('No target path provided.');
+    }
+
+    // If targetPath is not provided or it's not starting with a slash, it means it's a relative path
+    // in that case, we need to prepend the app's root directory to it
+    targetPath = getAbsolutePathForApp(targetPath);
+
+    // Extract options
+    const recipients = options.recipients || [];
+    const access = options.access || 'read';
+
+    // Validate access level
+    if (!['read', 'write'].includes(access)) {
+        throw new Error('Invalid access level. Must be "read" or "write".');
+    }
+
+    // Validate recipients
+    if (!Array.isArray(recipients) || recipients.length === 0) {
+        throw new Error('Recipients must be a non-empty array.');
+    }
+
+    // Prepare the share request
+    const shareData = {
+        recipients: recipients,
+        shares: [
+            {
+                $: 'fs-share',
+                path: targetPath,
+                access: access,
+            }
+        ]
+    };
+
+    // Make the API call to share the file
+    console.log(`api origin: ${puter.APIOrigin}`);
+    const response = await fetch(`${puter.APIOrigin}/share`, {
+        method: 'POST',
+        headers: {
+            'Content-Type': 'application/json',
+            'Authorization': `Bearer ${puter.authToken}`
+        },
+        body: JSON.stringify(shareData)
+    });
+
+    if (!response.ok) {
+        const errorText = await response.text();
+        throw new Error(`Share failed: ${response.status} ${errorText}`);
+    }
+
+    const result = await response.json();
+    return result;
+};
+
+export default share;
diff --git a/src/puter-js/src/modules/FileSystem/operations/write.js b/src/puter-js/src/modules/FileSystem/operations/write.js
index 878e61050c..0dcaa9d023 100644
--- a/src/puter-js/src/modules/FileSystem/operations/write.js
+++ b/src/puter-js/src/modules/FileSystem/operations/write.js
@@ -1,4 +1,4 @@
-import path from "../../../lib/path.js"
+import path from "../../../lib/path.js";
 import getAbsolutePathForApp from '../utils/getAbsolutePathForApp.js';
 
 const write = async function (targetPath, data, options = {}) {
@@ -56,7 +56,35 @@ const write = async function (targetPath, data, options = {}) {
     }
 
     // perform upload
-    return this.upload(data, parent, options);
+    const result = await this.upload(data, parent, options);
+
+    if (options.share) {
+        try {
+            // Call the share API after successful write
+            let share_result = await this.share(result.path, {
+                recipients: options.share.recipients || [],
+                access: options.share.access || 'read'
+            });
+            console.log('share_result', share_result);
+            
+            // Add share information to the result
+            result.share = {
+                status: share_result.status,
+                recipients: share_result.recipients || [],
+                shares: share_result.shares || []
+            };
+        } catch (error) {
+            console.error('Failed to share file after write:', error);
+            // Add error information to the result
+            result.share = {
+                status: 'error',
+                error: error.message,
+                recipients: []
+            };
+        }
+    }
+    
+    return result;
 }
 
 export default write;
\ No newline at end of file
diff --git a/tools/api-tester/README.md b/tools/api-tester/README.md
index 95d4eaebf5..44b47e7865 100644
--- a/tools/api-tester/README.md
+++ b/tools/api-tester/README.md
@@ -1,6 +1,6 @@
 # API Tester
 
-A test framework for testing the backend API of puter.
+A test framework for testing the API of puter backend and puter-js client.
 
 ## Table of Contents
 
@@ -43,6 +43,12 @@ All commands below should be run from the root directory of puter.
     node ./tools/api-tester/apitest.js --config=./tools/api-tester/config.yml
     ```
 
+4. (experimental) Run tests against the puter-js client:
+
+    ```bash
+    node ./tools/api-tester/apitest.js --config=./tools/api-tester/config.yml --client
+    ```
+
 ### Shorthands
 
 - Run unit tests only:
diff --git a/tools/api-tester/apitest.js b/tools/api-tester/apitest.js
index b5dcb9d734..9b6c5125d3 100644
--- a/tools/api-tester/apitest.js
+++ b/tools/api-tester/apitest.js
@@ -9,13 +9,14 @@ const { parseArgs } = require('node:util');
 
 const args = process.argv.slice(2);
 
-let config, report, suiteName;
+let config, report, suiteName, onlycase, bench, unit, stopOnFailure, id, puterjs;
 
 try {
     const parsed = parseArgs({
         options: {
             config: {
                 type: 'string',
+                default: './tools/api-tester/config.yml',
             },
             report: {
                 type: 'string',
@@ -24,6 +25,8 @@ try {
             bench: { type: 'boolean' },
             unit: { type: 'boolean' },
             suite: { type: 'string' },
+            'stop-on-failure': { type: 'boolean' },
+            puterjs: { type: 'boolean' },
         },
         allowPositionals: true,
     });
@@ -35,6 +38,8 @@ try {
         bench,
         unit,
         suite: suiteName,
+        'stop-on-failure': stopOnFailure,
+        puterjs,
     }, positionals: [id] } = parsed);
 
     onlycase = onlycase !== undefined ? Number.parseInt(onlycase) : undefined;
@@ -47,6 +52,7 @@ try {
         '\n' +
         'Options:\n' +
         '  --config=<path>  (required)  Path to configuration file\n' +
+        '  --puterjs         (optional)  Use puter-js puterjs\n' +
         '  --report=<path>  (optional)  Output file for full test results\n' +
         '  --suite=<name>   (optional)  Run only tests with matching suite name\n' +
         ''
@@ -58,6 +64,87 @@ const conf = YAML.parse(fs.readFileSync(config).toString());
 
 
 const main = async () => {
+    if (puterjs) {
+        // const run = require('./puter_js/__entry__.js');
+
+        const context = {
+            mountpoint: {
+                path: '/',
+            }
+        };
+
+        const ts = new TestSDK(conf, context, {});
+        const registry = new TestRegistry(ts);
+
+        await require('./puter_js/__entry__.js')(registry);
+
+        await registry.run_all_tests();
+
+        // await run(conf);
+        ts.printTestResults();
+        ts.printBenchmarkResults();
+        process.exit(0);
+        return;
+    }
+
+    const unit_test_results = [];
+    const benchmark_results = [];
+    for (const mountpoint of conf.mountpoints) {
+        const { unit_test_results: results, benchmark_results: benchs } = await test({ mountpoint });
+        unit_test_results.push(...results);
+        benchmark_results.push(...benchs);
+    }
+
+    // hard-coded identifier for ci script
+    console.log("==================== nightly build results begin ====================")
+
+    // print unit test results
+    let tbl = {};
+    for ( const result of unit_test_results ) {
+        tbl[result.name + ' - ' + result.settings] = {
+            passed: result.caseCount - result.failCount,
+            failed: result.failCount,
+            total: result.caseCount,
+            'duration (s)': result.duration ? result.duration.toFixed(2) : 'N/A',
+        }
+    }
+    console.table(tbl);
+
+    // print benchmark results
+    if (benchmark_results.length > 0) {
+        tbl = {};
+        for ( const result of benchmark_results ) {
+            const fs_provider = result.fs_provider || 'unknown';
+            tbl[result.name + ' - ' + fs_provider] = {
+                'duration (s)': result.duration ? (result.duration / 1000).toFixed(2) : 'N/A',
+            }
+        }
+        console.table(tbl);
+
+        // print description of each benchmark since it's too long to fit in the table
+        const seen = new Set();
+        for ( const result of benchmark_results ) {
+            if ( seen.has(result.name) ) continue;
+            seen.add(result.name);
+
+            if ( result.description ) {
+                console.log(result.name + ': ' + result.description);
+            }
+        }
+    }
+
+    // hard-coded identifier for ci script
+    console.log("==================== nightly build results end ====================")
+}
+
+/**
+ * Run test using the given config, and return the test results
+ * 
+ * @param {Object} options
+ * @param {Object} options.mountpoint
+ * @returns {Promise<Object>}
+ */
+async function test({ mountpoint }) {
     const context = {
         options: {
             onlycase,
diff --git a/tools/api-tester/puter_js/__entry__.js b/tools/api-tester/puter_js/__entry__.js
new file mode 100644
index 0000000000..3e8da689b4
--- /dev/null
+++ b/tools/api-tester/puter_js/__entry__.js
@@ -0,0 +1,27 @@
+const load_puterjs = require('./load.cjs');
+
+async function run(conf) {
+  const puter = await load_puterjs();
+  if (conf.token) {
+    puter.setAuthToken(conf.token);
+  } else {
+    throw new Error('No token found in config file. Please add a "token" field to your config.yaml');
+  }
+  return;
+};
+
+module.exports = async registry => {
+  const puter = await load_puterjs();
+  if (registry.t?.conf?.token) {
+    puter.setAuthToken(registry.t.conf.token);
+  } else {
+    throw new Error('No token found in config file. Please add a "token" field to your config.yaml');
+  }
+
+  registry.t.puter = puter;
+
+  console.log('__entry__.js');
+  require('./filesystem/__entry__.js')(registry);
+
+  // registry.add_test('filesystem', require('./filesystem/__entry__.js'));
+};
\ No newline at end of file
diff --git a/tools/api-tester/puter_js/filesystem/__entry__.js b/tools/api-tester/puter_js/filesystem/__entry__.js
new file mode 100644
index 0000000000..e56c81ceb4
--- /dev/null
+++ b/tools/api-tester/puter_js/filesystem/__entry__.js
@@ -0,0 +1,4 @@
+module.exports = registry => {
+    console.log('filesystem __entry__.js');
+    registry.add_test('write', require('./write.js'));
+};
\ No newline at end of file
diff --git a/tools/api-tester/puter_js/filesystem/write.js b/tools/api-tester/puter_js/filesystem/write.js
new file mode 100644
index 0000000000..35a7107f60
--- /dev/null
+++ b/tools/api-tester/puter_js/filesystem/write.js
@@ -0,0 +1,40 @@
+const chai = require('chai');
+chai.use(require('chai-as-promised'))
+const expect = chai.expect;
+
+module.exports = {
+    name: 'write',
+    description: 'a collection of tests for writing to the filesystem',
+    do: async t => {
+        const puter = t.puter;
+
+        await t.case('demo (whoami)', async () => {
+            const result = await puter.auth.whoami();
+            expect(result.username).to.equal('admin');
+        });
+
+        await t.case('write and share', async () => {
+            let result = await puter.fs.write('~/test.txt', 'hello');
+            expect(result.name).to.equal('test.txt');
+
+            result = await puter.fs.share('~/test.txt', {
+                recipients: ['tom', 'jerry'],
+                access: 'read',
+                withPermissions: true,
+            });
+            console.log('result', result);
+            expect(result.recipients.length).to.equal(2);
+        });
+
+        await t.case('write with share args', async () => {
+            let result = await puter.fs.write('~/test.txt', 'hello', {
+                share: {
+                    recipients: ['tom', 'jerry'],
+                    access: 'read',
+                },
+                withPermissions: true,
+            });
+            expect(result.share.recipients.length).to.equal(2);
+        });
+    }
+}
\ No newline at end of file
diff --git a/tools/api-tester/puter_js/load.cjs b/tools/api-tester/puter_js/load.cjs
new file mode 100644
index 0000000000..5cd17e008a
--- /dev/null
+++ b/tools/api-tester/puter_js/load.cjs
@@ -0,0 +1,13 @@
+const vm = require('vm');
+
+async function load_puterjs() {
+    const goodContext = {}
+    Object.getOwnPropertyNames(globalThis).forEach(name => { try { goodContext[name] = globalThis[name]; } catch { } })
+    goodContext.globalThis = goodContext
+    const code = await fetch("http://puter.localhost:4100/puter.js/v2").then(res => res.text());
+    const context = vm.createContext(goodContext);
+    const result = vm.runInNewContext(code, context);
+    return goodContext.puter;
+}
+
+module.exports = load_puterjs;
\ No newline at end of file