Welcome to this week’s DevNewsletter, bringing you last week’s startup news filled with devtool breakthroughs! We’ve noticed a big focus on AI observability and monitoring with tools helping developers track down hidden AI model errors and build web and native apps with less hassle. With AI bugs slipping past and automation scripts breaking, many of this week’s solutions deliver precise monitoring and clean APIs to keep your projects on track.
Curious about the latest advancements? Keep scrolling down.
🏆 Funding Wins
Lightrun Banner (Source: LinkedIn)
Lightrun Illuminates Debugging with $70M Boost
Founded in 2019, Lightrun empowers developers with real-time observability, enabling debugging in live applications without recompiling. The team has just secured $70M in a Series B round led by Accel and Insight Partners, joined by Citi, Glilot Capital, GTM Capital, and Sorenson Capital, bringing total funding to $110M. Kudos to Ilan Peleg (CEO), Leonid Blouvshtein (CTO) and the entire team for advancing AI-driven autonomous debugging and this achievement.
Now, we are setting our sights even higher. We are building a world where software autonomously remediates executed bugs in real time — before they ever impact customers. – Peleg
Explore the announcement at Lightrun.
Blacksmith Forges $3.5M for CI Revolution
With $1M ARR in under a year, Blacksmith powers millions of CI jobs for 600+ orgs like Ashby and Superblocks using a bare-metal cloud with gaming CPUs and NVMe storage. Founded in 2024 by Aditya Jayaprakash (CEO), Aayush Shah, and Aditya Maru, the team has raised $3.5M from GV and Y Combinator to scale their 2x faster, half-cost GitHub Actions runners. Congratulations to the crew!
Learn more at Blacksmith‘s Blog.
Variant’s $5.9M Sparks Creative AI Coding
Here to cultivate creativity with AI, Variant has just secured $5.9M from Kindred Ventures, Initialized Capital, and Y Combinator. Part of the YCF24 batch, founders Daniel Bulhosa Solórzano and Ben South Lee are passionate and driven in their approach to give developers and designers room to grow their ideas…”to branch, remix, and become what they’re meant to be” through an infinite canvas of ideas.
We are excited by this, are you? Join the waitlist here.
🚀 3, 2, 1… Launches
Daytona Cloud AI Agent Banner (Source: Product Hunt)
Daytona Launch Week Includes Huge Leap Forward with Agent-Native Infrastructure
Daytona, part of last week’s launch week, unveiled Daytona Cloud, purpose-built infrastructure for AI agents, not humans. Daytona addresses human-centric cloud limitations with sub-90ms sandbox spin-ups, stateful sandboxes, and native Docker support. The launch week also included the MCP Server for AI assistant integration, multi-region support across North America, Europe, and Asia, and a Web Terminal for debugging. Congrats to Ivan Burazin (CEO), Goran Draganić, Vedran Jukic, and the team for this launch.
Try it out today, early access includes $200 credits. Find out more here.
One Simplifies Coding for Web and Native Apps
Last week, One launched as a React framework letting developers write once for web and native platforms. Created by Nathan Wienert, a staff engineer at Uniswap Labs with a background at Vercel, One tackles fragmented development with a Vite plugin supporting SPAs, SSGs, SSRs, and React Native, featuring file-system routing and Tamagui for unified UI. It focuses on simplicity, with Zero sync engine integration planned.
“The inspiration is more of a Rails-like experience, where it’s just very simple,” – Wienert.
Check out the onestack.dev website.
Laminar Unveils Visual Debugging for Browser Agents
Laminar (YC S24), an open-source platform, launched an observability layer for browser agents, letting developers visualize agent execution. It captures detailed browser session videos synced with agent traces, helping developers spot exactly where and why agents fail, clarify decision-making visuals, and troubleshoot complex interactions. With two-line integration into Browser Use, their Index agent achieves 92% on WebVoyager for natural language automation.
Read the full write-up from Robert Kim and Dinmukhamed Mailibay to learn more here.
Hyberbrowser Banner (Source: LinkedIn)
HyperAgent Enhances Browser Automation with AI
Last week, Hyperbrowser open-sourced HyperAgent, a tool that fixes broken browser automation with AI-driven flexibility. It tackles brittle scripts, offering simple APIs like page.ai() for tasks like mapping routes or page.extract() for data grabs, with Playwright as a fallback. It scales to hundreds of browsers, supports multiple LLMs, includes stealth mode to dodge detection, and uses MCP for workflows like Google Sheets integration. HyperAgent empowers developers with adaptive, natural language automation. Congrats to founders, Shri Sukhani and Akshay Shekhawat!
Find out more and Star it on GitHub.
Raindrop Illuminates AI Product Monitoring
Raindrop, a Sentry-like platform to catch silent AI failures, ensuring reliable products, launches. Zubin Singh Koticha, Alexis Gauba, and Ben Hylak’s team built Raindrop to alert developers to issues like task failures or user frustration, linking directly to event traces for quick fixes. Features include real-time topic clustering and PII redaction, with wins highlighted to refine user experiences. The Pro tier adds custom issue tracking, topic clustering, signal detection, deep research, traces, and dataset creation. Companies like Clay.com, Websim and Tolans rely on it to improve their AI products, and we’re very excited by what we see here.
Explore at raindrop.ai.
Timescale Accelerates Real-Time Analytics
Last week, Timescale rolled out fresh tools to make real-time analytics a breeze without needing database migrations. 🐯 Ajay Kulkarni and 🐯 Michael Freedman’s team introduced Livesync for Postgres, streaming data with zero downtime, and Livesync for S3 with pgai Vectorizer for seamless data ingestion. Their Postgres setup with pgvector zips past Qdrant 11x in vector search speed. Developers get SQL Assistant for easy query-building from plain text and Insights for pinpoint debugging. With SOC 2, HIPAA, and GDPR support, security’s top-notch. Freshly named a Forbes 2025 Best Startup Employer, Timescale’s killing it. No surprise they were our DevTool of the Week back in Feb.
Read all about their launch week here.
🔦 DevTools of the Week
Arize AI Banner (Source: LinkedIn)
Arize AI Ignites AI Observability Excellence
All rise for Arize AI; this week’s developer tool of the week. Founded in 2020 by Jason Lopatecki and Aparna Dhinakaran in Berkeley, California, Arize AI solves the puzzle of unpredictable AI failures, delivering end-to-end observability for machine learning, LLMs, and AI agents.
With $131M raised, including a $70M Series C in February 2025, Arize serves clients like Uber and the U.S. Navy.
Unlike traditional monitoring tools, their platform, built on OpenTelemetry, is purpose-designed for AI, using LLM-as-a-Judge to catch data drift and biases. AI Copilot accelerates issue resolution, boosting developer productivity. Arize Phoenix, their open-source library, sees over two million monthly downloads, equips developers with tools for model monitoring and evaluation.
“Our open source Phoenix has just been growing, it’s been growing massively, and so I think we love that. We love open source,” -Dhinakaran (Source: TechCrunch Article)
As the AI observability market races toward $10.7B by 2033, Arize’s pre- and post-launch evaluations set the gold standard, ensuring trust and performance for enterprises and startups alike.
Congrats to the team on successes so far! Explore at arize.com and don’t forget to book your place at Observe 2025 in San Francisco on June 25th.
What a week for devtools, with big funding rounds powering AI debugging and fresh launches delivering sharp monitoring and coding solutions! Got a devtool story to share?
Email natalie@develocity.io for next week’s feature.
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