Founding Security Engineer | AI-Native Fintech

Colossus Technologies Group; New York (NY); On-site; USD 180,000 - 280,000; Full time

Job summary

Colossus Technologies Group, a US-based AI-native fintech startup, seeks a founding Security Engineer to own security across the organization. As the first dedicated security hire, you will design, build, and automate security systems for a rapidly growing platform used by major enterprises.

You will own cloud infrastructure security, identity and access controls, application security, and AI-security initiatives, partnering with engineering and leadership to create a scalable security function

Qualifications

• Strong hands-on engineering in enterprise, cloud, and application security.
• Experience building security capabilities in startups or high-growth teams.
• Solid software development or scripting experience, Python or Go.
• Practical experience with cloud infrastructure, Terraform, CI/CD, and security automation.
• Understanding of identity systems, authentication, authorization, and modern enterprise security controls.
• Experience with security compliance frameworks such as SOC 2, ISO 27001, or PCI.
• Interest in AI security and AI-driven security workflows.
• Enjoys ownership and collaboration with engineering teams.

Responsibilities

• Own cloud & infrastructure security, including IaC, production workloads, and deployment pipelines; build scalable guardrails.
• Own identity and enterprise security, including SSO, access controls, and secure integrations across internal systems.
• Lead application and product security, integrating security into the SDLC with threat modeling and vulnerability management.
• Address AI & agentic security, securing AI-powered products and workflows while leveraging AI to automate security processes.
• Drive security automation and internal tooling to reduce manual work and increase engineering autonomy.
• Define security strategy and architecture to scale with the company and its customers.
• Ensure compliance readiness and strong enterprise security controls as the business grows.

Skills

Python

Go

Terraform

CI/CD

Cloud security

Identity & access

SOC 2

ISO 27001

PCI

AI security

Tools

Terraform

Job description

Founding Security Engineer | AI-Native Fintech | ~$100M Raised | Series B

We're partnering with one of the fastest-growing AI-native fintech companies to hire their first dedicated Security Engineer. This is a rare opportunity to build a security function from the ground up at a company experiencing significant growth, backed by some of the most respected investors in technology.

Their AI platform is already being used by more than 150 companies, including Fortune 50 and Fortune 500 enterprises, and has processed over $3 billion in transactions.

As they continue scaling their engineering organization and enterprise customer base, security is becoming an increasingly critical part of the business.

The Opportunity

We're looking for a highly technical, hands-on security engineer who wants to take ownership of security across the organization.

This isn't a role where you'll inherit a mature security program or spend your time managing vendors and reviewing policies. You'll have the opportunity to design, build, and automate the systems that secure a rapidly growing AI-native business.

You'll work closely with engineering and leadership, with ownership spanning cloud infrastructure, corporate identity, application security, AI security, and compliance.

The goal is to build a modern, engineering-driven security function that enables the business to move faster, not slow it down.

What You'll Own

• Cloud & Infrastructure Security: Secure cloud environments, infrastructure-as-code, production workloads, and deployment pipelines. Build automated guardrails that scale alongside engineering.
• Identity & Enterprise Security: Own identity architecture, SSO, access controls, authentication, and secure integrations across internal systems and enterprise applications.
• Application & Product Security: Partner directly with software engineers to integrate security into the SDLC, including threat modeling, vulnerability management, and secure development practices.
• AI & Agentic Security: Help secure AI-powered products, agents, MCP integrations, and emerging AI workflows while leveraging AI to automate traditional security processes.
• Security Automation: Build internal tooling, self-service security capabilities, and automated workflows that reduce manual processes and give engineering teams greater autonomy.
• Compliance & Customer Trust: Drive security controls, audit readiness, and enterprise security requirements as the company expands relationships with some of the world's largest organizations.
• Security Strategy: Establish the technical foundations, priorities, and architecture for a security program designed to scale.

What We're Looking For

• Strong hands-on engineering background across several areas of enterprise, cloud, and application security.
• Experience building security capabilities in a startup or high-growth engineering organization.
• Solid software development or scripting experience, ideally Python or Go.
• Practical experience with cloud infrastructure, Terraform, CI/CD, and security automation.
• Understanding of identity systems, authentication, authorization, and modern enterprise security controls.
• Experience with security compliance frameworks such as SOC 2, ISO 27001, or PCI.
• Interest in AI security, agentic workflows, and using AI to solve real engineering and security problems.
• Someone who enjoys building, taking ownership, and working directly with engineering teams rather than operating exclusively in a governance or oversight capacity.

Why This Is Interesting

Timing: Join immediately following a major Series B, with significant capital, enterprise traction, and an expanding engineering organization.

Ownership: Be the first dedicated security hire, with the opportunity to shape the security architecture and establish how the company approaches security.

Technical Depth: Work across cloud, identity, application security, AI security, and automation rather than being confined to one narrow specialty.

Real Scale: Secure an AI platform already trusted by major enterprises and handling billions of dollars in transaction activity.

Career Growth: Help establish a security function that can grow with the business, with the opportunity to take on broader technical and organizational leadership over time.

We're looking for someone who wants to build security, not just maintain it.

If you're a strong security engineer who enjoys solving complex problems, writing code, and building scalable systems, this is an opportunity to make a meaningful impact at a pivotal stage of growth.