MentionFox lists 82 Developer tools companies for 2025. Of them, 81 are Y Combinator companies (the newest batch here is Fall 2025, with 15); 1 won an SBIR or STTR award.
Companies82
Y Combinator81
SBIR/STTR winners1
Other years
All years (678) 2026 (89) 2024 (91) 2023 (79) 2022 (64) 2021 (83) 2020 (54)
Developer tools startups in 2025
| Company | What it does | Date | Amount | Round / stage | Record |
|---|---|---|---|---|---|
| Apexquantum, Inc. | Optimizing quantum circuit compiler for quantum software and hardware developers | Award starts Oct 1, 2025 | $304,999 | SBIR Phase I | Federal award record |
| Amika | Infra to build your own software factory | Fall 2025 | Y Combinator batch | Y Combinator listing | |
| Compyle | The coding agent that actually collaborates with you | Fall 2025 | Y Combinator batch | Y Combinator listing | |
| dari.dev | The Routing Layer for AI Agents | Fall 2025 | Y Combinator batch | Y Combinator listing | |
| Fastshot | Lovable for mobile apps | Fall 2025 | Y Combinator batch | Y Combinator listing | |
| Kestrel AI | AI Agents for Platform Engineering | Fall 2025 | Y Combinator batch | Y Combinator listing | |
| Moss | Real-time semantic search for Conversational AI | Fall 2025 | Y Combinator batch | Y Combinator listing | |
| Nexus | We help non-technical teams build AI agents without engineers | Fall 2025 | Y Combinator batch | Y Combinator listing | |
| Parse | Build an API to interact with any website. | Fall 2025 | Y Combinator batch | Y Combinator listing | |
| Perseus | Applied Lab focused on Search in Latent Spaces. | Fall 2025 | Y Combinator batch | Y Combinator listing | |
| Radius | Code and browse in the same place | Fall 2025 | Y Combinator batch | Y Combinator listing | |
| s2.dev | API for unlimited, durable, real-time streams | Fall 2025 | Y Combinator batch | Y Combinator listing | |
| Scott AI | The planning layer for teams that build with coding agents | Fall 2025 | Y Combinator batch | Y Combinator listing | |
| Sourcebot | Helping humans and AI agents understand massive codebases | Fall 2025 | Y Combinator batch | Y Combinator listing | |
| Specific | The cloud platform built for coding agents | Fall 2025 | Y Combinator batch | Y Combinator listing | |
| The Context Company | Find what's losing you customers and money in your AI agent and fix it | Fall 2025 | Y Combinator batch | Y Combinator listing | |
| AgentMail | Email Inboxes for AI Agents | Summer 2025 | Y Combinator batch | Y Combinator listing | |
| args | A better GItHub | Summer 2025 | Y Combinator batch | Y Combinator listing | |
| Autosana | AI agents for E2E testing across mobile & web | Summer 2025 | Y Combinator batch | Y Combinator listing | |
| Cactus Compute | Automation Foundation Models For Tiny Devices | Summer 2025 | Y Combinator batch | Y Combinator listing | |
| Cyberdesk | Self learning computer use agent for developers | Summer 2025 | Y Combinator batch | Y Combinator listing | |
| Dedalus Labs | Compute substrate for AI agents | Summer 2025 | Y Combinator batch | Y Combinator listing | |
| Embedder | The Enterprise AI Platform for Embedded Software | Summer 2025 | Y Combinator batch | Y Combinator listing | |
| Fulcrum | The agentic debugger for AI systems | Summer 2025 | Y Combinator batch | Y Combinator listing | |
| Interfere | Give engineering, product, and design teams insight into unseen issues | Summer 2025 | Y Combinator batch | Y Combinator listing | |
| IronLedger.ai | AI-enabled Corporate Cards and Invoice Processing for Real Estate | Summer 2025 | Y Combinator batch | Y Combinator listing | |
| Lark | The E2E testing layer for AI-driven development | Summer 2025 | Y Combinator batch | Y Combinator listing | |
| Lotas | AI for quantitative trading | Summer 2025 | Y Combinator batch | Y Combinator listing | |
| Luminal | Making AI run fast on any hardware. | Summer 2025 | Y Combinator batch | Y Combinator listing | |
| Magnitude | Open source inference server for local models | Summer 2025 | Y Combinator batch | Y Combinator listing | |
| Modelence | Production infrastructure on autopilot | Summer 2025 | Y Combinator batch | Y Combinator listing | |
| Nozomio | product lab | Summer 2025 | Y Combinator batch | Y Combinator listing | |
| Okibi | Turns products into CLIs and agents into customers | Summer 2025 | Y Combinator batch | Y Combinator listing | |
| Omnara | Summer 2025 | Y Combinator batch | Y Combinator listing | ||
| Proliferate | Do your life's work with agents | Summer 2025 | Y Combinator batch | Y Combinator listing | |
| stagewise | The Open Source Agentic IDE | Summer 2025 | Y Combinator batch | Y Combinator listing | |
| Tesora | Frontier AI for Actuaries | Summer 2025 | Y Combinator batch | Y Combinator listing | |
| Uplift AI | Foundational Voice Models for regional languages | Summer 2025 | Y Combinator batch | Y Combinator listing | |
| VibeFlow | AI content manager that grows your company's online presence | Summer 2025 | Y Combinator batch | Y Combinator listing | |
| Attune | Faster builds, zero effort. | Spring 2025 | Y Combinator batch | Y Combinator listing | |
| Better Auth | The authentication framework for TypeScript | Spring 2025 | Y Combinator batch | Y Combinator listing | |
| Blaxel | The infrastructure for autonomous agents | Spring 2025 | Y Combinator batch | Y Combinator listing | |
| Bloom | Build and share mobile apps in seconds | Spring 2025 | Y Combinator batch | Y Combinator listing | |
| Capacitive | The data gateway for agents. | Spring 2025 | Y Combinator batch | Y Combinator listing | |
| Chiron | Grammarly for Math ✏️ | Spring 2025 | Y Combinator batch | Y Combinator listing | |
| Clidey | Turn scattered data into one platform for decision-making | Spring 2025 | Y Combinator batch | Y Combinator listing | |
| cubic | AI-powered code review platform | Spring 2025 | Y Combinator batch | Y Combinator listing | |
| Docket | AI agents for web testing | Spring 2025 | Y Combinator batch | Y Combinator listing | |
| Feyn | Custom models trained on your data | Spring 2025 | Y Combinator batch | Y Combinator listing | |
| Golf | Agentic AI Security and Governance | Spring 2025 | Y Combinator batch | Y Combinator listing | |
| Habit | Accelerating world models. | Spring 2025 | Y Combinator batch | Y Combinator listing | |
| Human Behavior | Understand your users beyond the numbers | Spring 2025 | Y Combinator batch | Y Combinator listing | |
| Method | Agents that improve | Spring 2025 | Y Combinator batch | Y Combinator listing | |
| MindFort | Autonomous Security Agents | Spring 2025 | Y Combinator batch | Y Combinator listing | |
| mlop | Experiment tracking for training ML models | Spring 2025 | Y Combinator batch | Y Combinator listing | |
| Parsewise | Multi-document processing for your risk teams, AI agents, pipelines | Spring 2025 | Y Combinator batch | Y Combinator listing | |
| Refresh | Training gyms for computer use and software engineering work | Spring 2025 | Y Combinator batch | Y Combinator listing | |
| StarSling | Self-Driving CI: fast AI-native GitHub Actions runners | Spring 2025 | Y Combinator batch | Y Combinator listing | |
| Theorem | Program verification so even your systems engineers can vibecode | Spring 2025 | Y Combinator batch | Y Combinator listing | |
| Tinfoil | Encrypted AI with verifiable privacy | Spring 2025 | Y Combinator batch | Y Combinator listing | |
| Vassar Robotics | Open-source semi-humanoid dev kit → home data → autonomy → 20h/wk | Spring 2025 | Y Combinator batch | Y Combinator listing | |
| Wavedash | Play the latest games in your browser with no downloads | Spring 2025 | Y Combinator batch | Y Combinator listing | |
| a0.dev | We make mobile apps using AI. | Winter 2025 | Y Combinator batch | Y Combinator listing | |
| Artifact | An Collaborative, AI-native IDE for Hardware Engineers | Winter 2025 | Y Combinator batch | Y Combinator listing | |
| assistant-ui | Open Source React.js Library for AI Chat | Winter 2025 | Y Combinator batch | Y Combinator listing | |
| Astro | The world’s first AI energy developer | Winter 2025 | Y Combinator batch | Y Combinator listing | |
| Browser Use | Agents that use the browser. | Winter 2025 | Y Combinator batch | Y Combinator listing | |
| Codevisor | The fastest native app for agentic engineering. | Winter 2025 | Y Combinator batch | Y Combinator listing | |
| Corsair | OpenRouter for Integrations | Winter 2025 | Y Combinator batch | Y Combinator listing | |
| Dexto | AWS for AI Agents | Winter 2025 | Y Combinator batch | Y Combinator listing | |
| Infinite | Global B2B Stablecoin Processor | Winter 2025 | Y Combinator batch | Y Combinator listing | |
| Lucidic AI | Reimagining how Machines Learn | Winter 2025 | Y Combinator batch | Y Combinator listing | |
| Mastra | The Javascript framework for building AI agents, from the Gatsby devs | Winter 2025 | Y Combinator batch | Y Combinator listing | |
| Onlook | Cursor for Designers | Winter 2025 | Y Combinator batch | Y Combinator listing | |
| Outship | Hire amazing engineers by seeing how they use AI | Winter 2025 | Y Combinator batch | Y Combinator listing | |
| Promptless | An AI teammate that automatically updates your customer-facing docs | Winter 2025 | Y Combinator batch | Y Combinator listing | |
| Quantstruct | AI documentation engineer – test & autoimprove stale product docs | Winter 2025 | Y Combinator batch | Y Combinator listing | |
| ReJot | We turn complex API integrations into drop‑in full‑stack libraries | Winter 2025 | Y Combinator batch | Y Combinator listing | |
| Subtrace | Zero code network tracer | Winter 2025 | Y Combinator batch | Y Combinator listing | |
| superglue | connect, migrate and implement enterprise systems | Winter 2025 | Y Combinator batch | Y Combinator listing | |
| TensorPool | Vercel For GPUs | Winter 2025 | Y Combinator batch | Y Combinator listing | |
| Woz | Winter 2025 | Y Combinator batch | Y Combinator listing |
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Figures come only from the record linked in each row; a blank means the record gives none. How these lists are built.