Launch HN: Simplex (YC S24) – Browser automation platform for developers

Hacker News (score: 17)
Found: October 02, 2025
ID: 1676

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Launch HN: Simplex (YC S24) – Browser automation platform for developers Hi HN! We’re Marco and Shreya, founders of Simplex (https://www.simplex.sh/). We’re building all the infrastructure you need for modern browser automation – including remote browsers, steerable web agents, and more.

Here’s a demo: https://youtu.be/7KpWJbOcm1Y

We’re excited to be posting on HN again! Back in January, we Show HN’d the earliest version of Simplex (https://news.ycombinator.com/item?id=42704160). We’ve now spent close to a year working with real customers, forward-deploying into their codebases, and building web agent systems for them from the ground up to understand what it takes to get agents working in production.

We built Simplex because we started seeing a pattern: companies would initially roll their own Playwright/Stagehand web automation solutions. This worked fine in the early prototype stages, but they’d quickly get overwhelmed with technical challenges as they productionized automations across all the websites their customers use.

As they scaled, they’d have to build and manage:

- Chrome infrastructure: You'll need remote browsers, extension support, browser settings for anti-bot detection/stealth, and a hundred more small fixes.

- DOM parsing: We’ve seen many web portals have really weird quirks (nested iframes, shadow DOM elements, dynamic loading, popups, unstable selectors, etc..) that are hard to parse with traditional/existing browser agents.

- Agent context engineering: Website state, user prompts, system prompts, past actions all take up a massive amount of context. Without managing this, agents can get caught in loops or take wrong actions.

- Caching/reliability: No matter how perfect your prompts are, it’s hard to guarantee consistency without caching/deterministic actions.

- Login/2FA: Solve captcha, fetch 2FA from email/text/Google Auth, encrypt/decrypt credentials to access portals blocked by login.

- Automation management: You’ll have to store all your prompts, scrapers, and agents, and find a way to make them reusable if you have the same workflows across different portals.

- User interface: Creating new workflows + debugging can take time. You’ll have to find easy ways to expose this to your engineers to make the process more efficient when you have hundreds of automations to build.

Simplex is a proper solution that handles all of the above for you. We offer both an UI/dashboard (which is what we use even as technical developers) and an extensive API for customers who are using Simplex in their existing AI agents. Our dashboard/API docs are here: https://simplex.sh/docs. We’d love for you to check them out!

You can get started for free with Simplex at (https://www.simplex.sh/) (you have to register to prevent abuse since we’re giving you a remote browser that connects to the internet).

Our first users have been AI companies across different industries like accounting, logistics/transportation, customer service, and healthtech. We’ve seen them:

- Fill out prior authorization forms on medical provider portals

- Download hundreds of PDFs from grocer portals across the US

- Automate and scrape structured data from traditional ERPs like NetSuite

- Submit bids/shipments on logistics/TMS portals

- Scrape lawyer/doctor license information across public government portals

- And more!

We’re excited to see more use cases as we open up the platform – this is our first time doing self-serve.

Wanted to end with a quick thank you to HN. The feedback on our first Show HN gave us confidence to steer our product in this direction, and has deeply shaped the last year of our lives. We’d love feedback, especially from anyone who’s tried solving this problem or built similar tools.

Happy to answer questions and looking forward to your comments!

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