Y Combinator companies

The company knowledge base that updates itself

Simulate how any product change will perform before shipping.

One group chat to hear and steer your coding agents.

On-device knowledge graph engine for enterprises

Effortlessly deploy cloud software factories.

The runtime data layer for agents to monitor and debug apps

The harness company

Engineering Intelligence and Token Optimization for the AI-Coding Era

Lovable for internal tools

Let your users build their own features on top of your product

Ship more code with confidence

Collaborative AI app builder for teams

Marketing campaigns from everything your team ships

Helping your company find 10x engineers.

We help software companies get discovered and used by AI agents

Ship software faster with portable, self contained virtual machines.

Code review platform for humans and agents

Make software self-healing

Building self-improving software

/dev/fast is the AI-native code forge

UI building blocks for the agentic internet

Claude code for Mechanical Engineers

The first AI QA engineer that understands your code

Anyone can create real games with AI

AI Video Production for Professionals

Plan mode for complex features

Media infra for consumer apps

Make everyone on your team an engineer

The agentic coding app for complex tasks.

Accelerate Product Iteration

the brainrot ide

Localhost service isolation and orchestration for git worktrees

The coding agent that actually collaborates with you

Lovable for mobile apps

Build an API to interact with any website.

Intelligence that moves the world

Visual editor to design in production code

AI FDE Engine that runs your engineering workflows

A better GItHub

AI agents for E2E testing across mobile & web

Vibe code, test, and deploy Swift apps. All from your iPhone.

Hardware-Aware AI for Embedded Software Development

The GD&T Analysis Platform for Engineering Drawings

The easiest way for non-coders to build apps with AI.

Create Whiteboard Explainer Videos with AI from a Prompt or Document

Give engineering, product, and design teams insight into unseen issues

The E2E testing layer for AI-driven development

Code with local models, zero setup

Build production-ready apps with AI

Infrastructure Cartography

The Cursor for Chip Design - Delivering Silicon-Ready Chip Designs…

Physics-based foundation models for CAD optimization.

Faster builds, zero effort.

The authentication framework for TypeScript

Build and share mobile apps in seconds

Turn scattered data into one platform for decision-making

AI-powered code review platform

AI agents for web testing

Turn your hardest documents into reliable data

Understand your users beyond the numbers

Experiment tracking for training ML models

Software tool for designing robots and machines

Automatically write and update internal docs with every code commit.

Design a chip in minutes

Open-source agents to build predictive ML models from a prompt

Self-Driving CI: fast AI-native GitHub Actions runners

Program verification so even your systems engineers can vibecode

Secure internal apps. Built by AI in seconds. Powered by your data.

We make mobile apps using AI.

An Collaborative, AI-native IDE for Hardware Engineers

Open Source React.js Library for AI Chat

AI-Powered Hardware System Design Software

Frontier AI research to advance game development

Cursor for Designers

Operand — Private-Markets Intelligence

Real-time AI Voice Translation for Developers

An AI teammate that automatically updates your customer-facing docs

AI documentation engineer – test & autoimprove stale product docs

We turn complex API integrations into drop‑in full‑stack libraries

Electrical Engineering Components Compaion

Daily productivity tracker

Zero code network tracer

Lovable for Chrome Plugins

AI to understand and then route engineering work

Claude Code plugin that reduces token consumption and cost by 50%

The Cursor for Xcode

AI CAD for AEC

The IDE for the parallel age

The free coding agent

Building Dev Infra for AI Software Engineers

Ship 2-3x faster without AI slopping up your codebase

The Localization Engineering Platform

AI for life sciences documents

AI powered debugging notebooks for incident response

The Mobile Development Platform

Easy and secure customer cloud deployments

All-in-one AI creative platform

Stripe for telephony

Creative intelligence

The Lovable & Replit killers