Compare Castle vs. Foil

Auth0 takes a modern approach to Identity and enables organizations to provide secure access to any application, for any user. Auth0 is highly customizable, and simple yet flexible. Safeguarding billions of login transactions each month, Auth0 delivers convenience, privacy, and security so customers can focus on innovation. With Auth0, you can rapidly integrate authentication and authorization for web, mobile, and legacy applications, with new Fine Grained Authorization (FGA) that goes beyond role-based access control.

FusionAuth is the authentication and authorization platform engineered for developers who demand flexibility and control. Built from the ground up to integrate with any stack, every feature — from user registration to MFA and SSO — is exposed via a modern, well-documented API. Support for every major identity protocol is included out of the box: OIDC, SAML, OAuth2, JWT, passwordless login, social sign-on, and more. Whether you’re building a greenfield app or retrofitting auth into a legacy system, FusionAuth adapts to your use case — not the other way around. Need compliance? FusionAuth helps you meet GDPR, HIPAA, and COPPA standards quickly and reliably. Deploy it your way: install on Linux, Windows, macOS, Docker, or Kubernetes — or go with FusionAuth Cloud, our managed SaaS hosting. No black boxes. No vendor lock-in. Just powerful, customizable auth that works the way you do.

c/side: The Client-Side Platform for Cybersecurity, Compliance, and Privacy Monitoring third-party scripts effectively eliminates uncertainty, ensuring that you are always aware of what is being delivered to your users' browsers, while also enhancing script performance by up to 30%. The unchecked presence of these scripts in users' browsers can lead to significant issues when things go awry, resulting in adverse publicity, potential legal actions, and claims for damages stemming from security breaches. Compliance with PCI DSS 4.0.1, particularly sections 6.4.3 and 11.6.1, requires that organizations handling cardholder data implement tamper-detection measures by March 31, 2025, to help prevent attacks by notifying stakeholders of unauthorized modifications to HTTP headers and payment information. c/side stands out as the sole fully autonomous detection solution dedicated to evaluating third-party scripts, moving beyond reliance on merely threat feed intelligence or easily bypassed detections. By leveraging historical data and artificial intelligence, c/side meticulously analyzes the payloads and behaviors of scripts, ensuring a proactive stance against emerging threats. Our continuous monitoring of numerous sites allows us to stay ahead of new attack vectors, as we process all scripts to refine and enhance our detection capabilities. This comprehensive approach not only safeguards your digital environment but also instills greater confidence in the security of third-party integrations.

ZeroPath (YC S24) is an AI-native application security platform that delivers comprehensive code protection beyond traditional SAST. Founded by security engineers from Tesla and Google, ZeroPath combines large language models with deep program analysis to deliver intelligent security testing that finds real vulnerabilities while dramatically reducing false positives. Unlike traditional SAST tools that rely on pattern matching, ZeroPath understands code context, business logic, and developer intent. This enables identification of sophisticated security issues including business logic flaws, broken authentication, authorization bypasses, and complex dependency vulnerabilities. Our comprehensive security suite covers the application security lifecycle: 1. AI-powered SAST 2. Software Composition Analysis with reachability analysis 3. Secrets detection and validation 4. Infrastructure as Code scanning 5. Automated PR reviews 6. Automated patch generation and more... ZeroPath integrates seamlessly with GitHub, GitLab, Bitbucket, Azure DevOps and many more. The platform handles codebases with millions of lines across Python, JavaScript, TypeScript, Java, Go, Ruby, Rust, PHP, Kotlin and more. Our research team has been successful in finding vulnerabilities like critical account takeover in better-auth (CVE-2025-61928, 300k+ weekly downloads), identifying 170+ verified bugs in curl, and discovering 0-days in production systems at Netflix, Hulu, and Salesforce. Trusted by 750+ companies and performing 200k+ code scans monthly.

Uniqkey is Europe’s leading password and access manager. It simplifies employee security while empowering companies with enhanced control over their cloud infrastructure, access security, and employee management. Uniqkey combats the most significant threats to company infrastructure by safeguarding critical systems and company credentials with state-of-the-art encryption. It also offers unique insights and a comprehensive view of IT infrastructure, employee access, and security scores, making it a valuable tool for IT teams to monitor security policies and assess the impact of awareness campaigns with confidence. With powerful integrations and synergies with existing infrastructure such as Microsoft, IT managers can quickly provision or de-provision users for seamless onboarding and offboarding, all while protecting their entire IT infrastructure with advanced encryption. Engineered by leading European security experts, we leverage the latest encryption methodologies and technology, including offline encryption of all our data. Our modern tech stack and servers, hosted locally in Denmark, ensure maximum security, data integrity, and compliance with European regulations, providing our customers with peace of mind.

Cloudflare is the foundation of your infrastructure, applications, teams, and software. Cloudflare protects and ensures the reliability and security of your external-facing resources like websites, APIs, applications, and other web services. It protects your internal resources, such as behind-the firewall applications, teams, devices, and devices. It is also your platform to develop globally scalable applications. Your website, APIs, applications, and other channels are key to doing business with customers and suppliers. It is essential that these resources are reliable, secure, and performant as the world shifts online. Cloudflare for Infrastructure provides a complete solution that enables this for everything connected to the Internet. Your internal teams can rely on behind-the-firewall apps and devices to support their work. Remote work is increasing rapidly and is putting a strain on many organizations' VPNs and other hardware solutions.

Sumsub is a single verification platform that allows you to onboard more customers worldwide, speed up their access, reduce costs, and fight digital fraud. Sumsub combines effective verification flows with higher conversion rates worldwide through a powerful, all in one suite designed for a wide variety of needs: KYC/AML verification, KYB verifications, payment fraud prevention and face authentication.

Don't let fraud erode your bottom line, damage your reputation, or stall your growth. FraudNet's AI-driven platform empowers enterprises to stay ahead of threats, streamline compliance, and manage risk at scale—all in real-time. While fraudsters evolve tactics, our platform detects tomorrow's threats, delivering risk assessments through insights from billions of analyzed transactions. Imagine transforming your fraud prevention with a single, robust platform: comprehensive screening for smoother onboarding and reduced risk exposure, continuous monitoring to proactively identify and block new threats, and precision fraud detection across channels and payment types with real-time, AI-powered risk scoring. Our proprietary machine learning models continuously learn and improve, identifying patterns invisible to traditional systems. Paired with our Data Hub of dozens of third-party data integrations, you'll gain unprecedented fraud and risk protection while slashing false positives and eliminating operational inefficiencies. The impact is undeniable. Leading payment companies, financial institutions, innovative fintechs, and commerce brands trust our AI-powered solutions worldwide, and they're seeing dramatic results: 80% reduction in fraud losses and 97% fewer false positives. With our flexible no-code/low-code architecture, you can scale effortlessly as you grow. Why settle for outdated fraud and risk management systems when you could be building resilience for future opportunities? See the Fraud.Net difference for yourself. Request your personalized demo today and discover how we can help you strengthen your business against threats while empowering growth.

Streamline event calendar management and online registration with Trumba. It's perfect for virtual, in-person or hybrid events. Trumba offers an innovative and highly customizable event calendar platform preferred by colleges and universities, hospitals and health systems, local government, communities and other organizations worldwide. Trumba also offers a HIPAA-compliant solution for hospitals and healthcare organizations and will enter into a BAA with covered entities. Trumba calendars can be easily embedded into your website or published as fully-hosted pages that match your online branding. Attendees can easily find events, subscribe to calendars, register/pay and stay informed of changes. Trumba can integrate with other calendars to provide a one-stop experience for your users and optimize workflows internally. Trumba customers love the ease of implementation services and ongoing customer support. Online demos and free trials are available upon request (no credit card info required).

Regpack is an online onboarding, registration, and payments software used by thousands of organizations worldwide. Regpack works with a variety of businesses to automate their onboarding process, collect client information, and charge automatically for their services. Whether you're organizing an event, managing client billing, organizing a trip or camp, or offering courses and classes (virtual too!), Regpack can help you make your registration and payment processes a breeze with its unique technology and comprehensive set of features. Top features include recurring billing, payment plans, automated payment collection, custom form builder, built-in email tools, dynamic reporting, and more.