The tunneling studio developers actually want to open.
Instant zero-config public tunnels with Resilient Standby Mode, automatic Vite and FastAPI port sniffing, live traffic inspection, and 1-click IDE jumping. Native Rust binary, 12MB RAM, zero cloud telemetry.
Network Hub
Monitoring 1 active tunnel · Dynamic DNS resolution & 50ms handshake polling.
Auto-detects any dev server on localhost
Zero manual port forwarding or configuration files. Proxync silently sniffs active listening sockets and fingerprints your framework the instant your server boots.
Engineered to eradicate webhook and API friction.
Everything you need to expose, inspect, and debug local services — in one unified, lightweight desktop workspace.
Resilient Standby Tunnels
When your dev server restarts during code editing (HMR) or crashes, Proxync holds incoming webhooks in standby and delivers them the instant localhost rebinds. Zero broken links, zero 502 errors.
Traffic Inspector & Bot Shield
Capture live HTTP and WebSocket traffic flowing into your local services. Built-in heuristic filtering automatically strips out automated bot scans (/.env, /.git) so your feed stays clean.
1-Click IDE Deep Linking
Bridge runtime traffic with your editor. Click directly on any captured request or stack trace to open the exact route handler file and line number inside Cursor or VS Code.
Local-First & SSRF Shield
Your workspaces, keys, and traffic payloads stay on your computer in local JSON and SQLite storage. Strict loopback whitelisting blocks SSRF attempts against private subnets.
Compare the Developer Ergonomics
| Capability | Proxync Studio | ngrok | Cloudflare | Postman |
|---|---|---|---|---|
| Standby Survival (Vite/Node restart) | Native Socket Guard (0 drops) | 502 Bad Gateway drops | Connection refused drops | N/A (No tunnels) |
| Account / Cloud Auth Required | Zero signup / 100% anonymous | Mandatory cloud token | Requires account & DNS | Mandatory cloud login |
| Native Desktop UI Studio | Tauri v2 Native Binary | Web dashboard only | CLI daemon only | Heavy Electron app |
| RAM Footprint | ~12MB (Pure Rust) | ~85MB | ~120MB | ~450MB+ |
| Live Visual JSON Diff + Replay | Built-in + 1-Click IDE Jump | Replay only (No diff) | None | Manual cURL inspection |
| Process Lifecycle & Teardown | Atomic POSIX PGID (Zero Orphans) | Orphaned workers hold ports | Manual daemon kill | N/A |
| Data Privacy & Security | Local SQLite + SSRF Intranet Shield | Cloud logged | Edge telemetry | Workspaces cloud synced |
| License & Pricing | Apache 2.0 Free Forever | $10 – $20 / user / mo | Free tier / Enterprise | $14 – $49 / user / mo |
Up and running in under 60 seconds.
No mandatory cloud account. No YAML configuration wizards. No credit card required.
Auto-Detect Local Server
Proxync inspects listening ports on your machine in milliseconds, automatically discovering Vite, Next.js, or FastAPI servers without manual port flags.
Launch Resilient Tunnel
Generate a fast public HTTPS link with hardware-signed certs. When your server restarts on save, Standby Mode holds the URL so webhooks never fail.
Inspect & Jump to Code
Watch live request payloads stream in. Spot an error or unexpected value? Click once to jump directly to that controller file and line in your code editor.
Loved by builders who ship fast.
From freelance full-stack engineers and agency dev teams to solo indie SaaS founders.
“As a freelance developer, I used to waste 20 minutes deploying WIP code to a remote staging server just so my client or QA could test a 5-minute UI fix on their phone. With Proxync, I just click Share, send them the link on Slack, and they test live while it's still running on my laptop.”
“Standby Mode is the killer feature every solo dev needs. When you're vibe coding in Cursor and your dev server restarts on every file save, traditional tunnels die and break your Stripe and Clerk webhooks. Proxync quietly holds the connection alive. Haven't had a 502 error in weeks.”
“Our QA team can test PRs against our local backend in real time without waiting for heavy Docker builds or cloud staging pipelines. If a test fails, I see the raw webhook payload immediately in the Traffic Inspector and jump straight to the exact line in VS Code.”
“Having an API testing studio built directly into the desktop app that bypasses browser CORS issues is huge. Best part is zero cloud tracking—our agency signs strict client NDAs, and with Proxync all test auth tokens and customer payloads stay 100% on my machine.”
Questions,
answered.
Everything you need to know about running Proxync locally on your workstation.
Yes. Proxync is built on a strict 100% local-first architecture: zero customer payloads, tokens, headers, or request histories are ever transmitted to or stored on third-party cloud infrastructure. All data resides strictly on your machine in local JSON and SQLite storage. An integrated SSRF Intranet Shield blocks private network scanning, and diagnostic logs automatically redact Authorization headers and API keys, making Proxync safe under strict enterprise NDAs, SOC 2 compliance, and healthcare environments.
Yes! When you click Share, Proxync assigns an instant HTTPS public web link (like https://px-*.proxync.dev). Anyone on iOS, Android, or desktop can open that link directly in their standard mobile browser to test your local app in real time. They never have to install Proxync, configure DNS, or create an account.
Unlike traditional tunneling CLI tools that crash and return 502 Bad Gateway when you restart your server or hot-reload code, Proxync holds your public URL in Standby. External webhooks from Stripe, GitHub, or Shopify receive a temporary holding response, and buffered requests are delivered the moment your dev server boots back up.
Browser extensions and web-based API tools run inside your web browser's security sandbox, which strictly enforces Cross-Origin Resource Sharing (CORS) rules. Proxync's Playground executes requests natively through our desktop Rust networking engine directly at the OS socket level, where browser CORS restrictions do not apply.
Yes. You can run Next.js on port 3000, FastAPI on port 8000, and a backend service on 4000 simultaneously. Proxync automatically discovers each listening port, assigns independent public URLs, and tags every incoming request in the Traffic Inspector with deterministic port and server metadata so logs never get mixed up.
Proxync is 100% free and open-source under the permissive Apache 2.0 license. There are no monthly subscriptions, no tunnel session duration limits, no rate limits, and no credit card required. You download the app and start building.
Upgrade your local tunneling workflow.
Free, local-first, and open source under Apache 2.0. Install the native desktop studio with Resilient Standby Mode and 1-Click IDE jumping.