SAN FRANCISCO, Oct. 08, 2025 (GLOBE NEWSWIRE) — Arcjet, the security platform that ships with your code, has raised $8.3 million in Series A funding to help developers stay ahead of a new generation of AI-driven attacks. This funding brings Arcjet’s total funding to $12 million and will accelerate product development of Arcjet’s developer-first native security platform for modern applications.
The round was led by Plural and Ott Kaukver, former CTO of Twilio and Checkout.com, with participation from previous investors Andreessen Horowitz and Seedcamp, as well as new strategic angels including Jeff Lawson (former CEO, Twilio) and Feross Aboukhadijeh (CEO, Socket).
Meeting a fast-changing security landscape
Bots now outnumber humans online, with 37% of all traffic coming from malicious sources. AI is amplifying the problem, creating adaptive, automated attacks that can bypass traditional defenses and inflict real costs.
From fake sign-ups to spam AI bots scraping content and overwhelming APIs, developers are under pressure to protect their apps in a world where traditional security tools are no longer fit for purpose.
Bot attacks cost businesses $116 billion last year, with companies with revenue of at least $100 billion facing 26% of all incidents.
Expert security AI embedded in every request
In a separate announcement, Arcjet today also launched a new local attack detection model that brings AI-powered threat analysis directly into the application code. Arcjet’s local AI model performs attack detection directly inside the request handler, analyzing user behavior alongside business context to stop sophisticated threats that bypass conventional defenses.
“Legacy security tools – designed for a pre-AI era and operating at the network perimeter – see packets, not users or business context,” said David Mytton, Arcjet founder and CEO. “They can’t provide the deep, granular level of protection needed to distinguish valuable AI traffic from genuine threats or respond at the pace of AI innovation. As a result, developers are left with security approaches that lack application & business context, slowing release cycles and creating costly false positives while missing sophisticated attacks.”
Arcjet takes a different approach. By embedding an AI directly into the codebase and inspecting every request in milliseconds without slowing deployment, Arcjet’s protections become part of the application itself, so they are testable and deployable like any other feature.
Backed up by analysis which adapts in real time, Arcjet empowers developers to stop fraud and abuse from the first line of code. The platform allows developers to collaborate with security teams to stop attacks, without changing architecture, deploying agents or configuring proxies.
Early traction with AI and e-commerce
Arcjet’s approach is already resonating with developers building in high-stakes environments. More than 1000 developers across AI and e-commerce are using Arcjet to protect more than 500 production applications processing millions of requests every day.
One early Arcjet customer was able to reduce serverless cloud costs for their content-heavy community forums by 66% with Arcjet’s protections against malicious bot scraping. Another was able to rapidly secure a new finance platform against common attacks, completing a security audit ahead of a crucial launch deadline.
Two of the largest user groups to date are:
- AI application developers protecting against bot abuse and automated spam signups, where every malicious request translates into real compute cost.
- E-commerce teams fighting increasingly sophisticated scraping and fraud attempts that can hit revenue and undermine customer trust.
Built for developers, by developers
“Security has to live inside your code if it’s going to keep up with modern threats,” Mytton added. “We built Arcjet to make AI-powered defenses a native part of the development process – with minimal overhead and APIs that feel familiar. This funding will accelerate our mission to make embedded in-code protection the default for modern applications.”
Mytton previously founded and scaled infrastructure monitoring platform Server Density (acquired by StackPath) and spent five years publishing the Console.dev newsletter, profiling developer tools.
Backing from industry leaders
Sten Tamkivi, partner at Plural, said, “David is an exceptional repeat founder who combines deep technical expertise with a rare understanding of developers’ needs. The traction and credibility that Arcjet has built within a fairly short period of time is really remarkable – thousands of live websites now trust Arcjet to protect them from potentially existential threats. At Plural, we back serious founders who execute with pace and conviction. David and his team are doing exactly that.”
“Cybersecurity provides a pillar of trust for the digital economy,” said Ott Kaukver. “In modern web development where developers run their code at the edge, the traditional single wall of security can no longer reliably protect an app or a business. By embedding protection directly into code, Arcjet is shaping a safer future for the internet.”
“As software development accelerates with AI agents, AI coding tools, and new frameworks, security needs to move just as quickly,” said Zane Lackey, general partner at Andreessen Horowitz. “Arcjet’s approach is groundbreaking because it embeds AI defenses directly inside the code, analyzing every request in real time without slowing developers down. This is the kind of developer-first innovation that can redefine how modern applications stay secure.”
“AI is transforming how attackers operate, but what developers can build to mitigate,” commented Carlos Eduardo Espinal, managing partner at Seedcamp. “Arcjet tackles this by shipping security with code, making protection part of its DNA rather than an afterthought. This is the kind of foundational shift we look for at Seedcamp, and we’re proud to support the team as they pioneer the next generation of cybersecurity.”
About Arcjet:
Arcjet is building the security platform that ships with your code – expert security AI embedded in every request. Built to integrate directly into modern codebases, Arcjet enables fast-growing teams to embed security into their codebase without sacrificing flexibility. Founded in 2023 by David Mytton, Arcjet is already deployed in 500+ production apps and backed by Plural, Ott Kaukver, Andreessen Horowitz, Seedcamp, and 20+ leading devtools & security angels. https://arcjet.com/
About Plural:
Plural is an early-stage investment fund that backs the most ambitious founders on a mission to change the world through technology. Plural launched in June 2022 with the aim to give serious founders in Europe investors with experience to match their ambition. Based in Tallinn, Estonia, and London, UK, Plural’s mission is to have GDP-level impact on Europe, address systemic risks and reduce the opportunity gap worldwide through the companies it backs. https://pluralplatform.com
Plural press contact: Antonella Scimemi, antonella@burlington.cc
Arcjet press contact: Jason Throckmorton, jason@titletk.co
