C

Client-side Development

Autonomous AI script detection and optimization

Website

Overview

C Side provides an autonomous, AI-powered tool for detecting and optimizing third-party scripts used in web browsers. The service targets businesses that handle sensitive data (e.g., payments) and must meet security regulations. It continuously monitors third-party scripts for unauthorized changes and risky behavior, helping prevent security breaches and reputational or legal harm. The product is delivered as a subscription, offering ongoing monitoring, security improvements, and performance optimization (including caching of static scripts) to boost website speed and reliability. Unlike competitors that rely mainly on threat feeds, C Side analyzes script payloads and behaviors with AI and historical context to deliver more accurate detection and optimization. The company’s goal is to reduce risk and improve compliance and performance for e-commerce platforms, financial institutions, and other online services that use third-party scripts.

Significant Headcount Growth

Work here?Claim your company

About Client-side Development

Simplify's Rating
Why Client-side Development is rated
C+
Rated C on Competitive Edge
Rated B on Growth Potential
Rated C on Differentiation

Industries

Data & AnalyticsEnterprise SoftwareCybersecurity

Company Size

11-50

Company Stage

Seed

Total Funding

$7.7M

Headquarters

San Francisco, CA

Founded

2024

Get referred to Client-side Development

See people who can refer or advise you

Simplify Jobs

Simplify's take

What believers are saying

  • Uncork Capital led c/side's $6 million seed, lifting total funding to $7.7 million.
  • May 29, 2026 GA release broadened monitoring to automated browsers and spoofed bots.
  • March 17, 2026 Jira and Linear integrations push alerts into customer workflows.

What critics are saying

  • Mandos shows about 16 employees and a 20% headcount drop by September 2026.
  • Cloudflare, Akamai, and Imperva already bundle script inspection into broader security suites.
  • If PCI DSS demand slows, c/side lacks scale to survive a platform-bundling response.

What makes Client-side Development unique

  • c/side watches third-party JavaScript in real time, not just threat feeds or signatures.
  • Its August 14, 2026 CSP Builder converts observed hosts into deployable policies.
  • May 29, 2026 Fingerprint Dashboard and AI Agent Detection extend beyond script security.

Help us improve and share your feedback! Did you find this helpful?

Funding

Total Funding

$7.7M

Above

Industry Average

Funded Over

2 Rounds

Seed funding is usually the first official round after pre-seed, when a startup has a prototype or concept. It’s typically used to develop the product, test the market, and start building the team. Investors here are often angel investors or early-stage venture capitalists.
Seed Funding Comparison
Above Average

Industry standards

$3.3M
$2M
$2.3M
$3M
$6M

Benefits

  • Remote Work Options
  • Unlimited Paid Time Off
  • Stock Options

Growth & Insights and Company News

6 month growth

5%

1 year growth

5%

2 year growth

17%
Associated Press
Feb 5th, 2026
cside launches AI agent detection toolkit to identify and manage agentic traffic from consumer devices

cside, an AI-powered website security company, has launched its AI Agent Detection toolkit, enabling businesses to identify and manage traffic from AI agents operating through both traditional automated browsers and AI-powered browsers on consumer devices. The solution detects automated browsers like Comet and ChatGPT Atlas, as well as agentic browser extensions. It allows organisations to customise website experiences based on specific agent types, dynamically modify page elements, and provide observability into agentic traffic patterns. The toolkit addresses a gap in legacy bot detection systems, which cannot identify agents operating within consumer devices. Businesses can use it for security management, revenue optimisation through dynamic pricing, compliance enforcement, or user experience customisation. The solution integrates with cside's VPN detection capabilities for comprehensive traffic intelligence and deploys via a simple SDK.

Associated Press
Jan 21st, 2026
cside launches Privacy Watch to monitor third-party website scripts for GDPR and CPRA compliance

cside, an AI-powered website security company, has launched Privacy Watch, a platform that monitors and prevents privacy violations from third-party scripts on websites. The solution addresses compliance with regulations including GDPR, CPRA and HIPAA through continuous monitoring, evidence logs and regulation-specific reports. The platform targets a significant blind spot: 94% of modern websites use third-party scripts, but privacy teams lack visibility into how these data processors handle personal information like IP addresses and emails. Privacy Watch uses AI to detect unauthorised data collection, track cross-border data transfers and flag scripts firing before user consent. The launch responds to tightening global privacy regulations, with 20 new US state-level privacy laws enacted between 2023 and 2026, and increasing civil lawsuits over data leaks.

HIT Consultant
Dec 3rd, 2024
What All Healthcare It Leaders Must Understand About The Kaiser Permanente Breach

Simon Wijckmans, CEO and founder of c/sideOf the many, many facets of healthcare-industry cybersecurity that IT leaders must be aware of, browser-side attacks and data leaks have particularly high potential to blindside an organization. Just ask leading healthcare provider Kaiser Permanente, which recently suffered a gargantuan data breach compromising the sensitive personal information of 13.4 million past and present insurance holders. The source of this breach wasn’t a nefarious attacker, although it could have been. In this case, careless management of browser-side third-party scripts resulted in unintentional and improper sharing of patients’ data and browsing behavior with external vendors and advertisers.The incident: why third-party browser scripts are a first-rate security concernThe data breach incident stemmed from Kaiser Permanente’s use of tracking codes designed to understand user behavior and usage patterns on the company’s websites and mobile applications. That tracking code captured data including patients’ names, IP addresses, their login status, the web pages they visited, and the search terms they entered to find information in Kaiser’s health encyclopedia. Unfortunately, third-party scripts active on Kaiser’s websites and mobile apps then inadvertently transmitted that data to third-party advertisers.  Tracking scripts used by healthcare-industry organizations must comply with HIPAA and other privacy regulations, and Kaiser reported the breach to the U.S

World Of Software
Sep 16th, 2024
C/side raises $6M to prevent supply chain attacks by securing third-party scripts - News

Cybersecurity startup Client-side Development Inc., which does business as C/side, said today it has closed on a $6 million seed funding round to accelerate the development of its tools for monitoring, optimizing and securing browser-side third-party scripts.

FinSMEs
Sep 16th, 2024
c/side Raises $6M in Seed Funding

c/side, a San Francisco, CA-based cybersecurity company with tools for monitoring, optimizing, and securing vulnerable browser-side third-party scripts, raised $6M in Seed funding

Recently Posted Jobs

Sign up to get curated job recommendations

There are no jobs for Client-side Development right now.

Find jobs on Simplify and start your career today

We update Client-side Development's jobs every few hours, so check again soon!Browse all jobs