Introduction
Cloud infrastructure is the backbone of modern financial services. But without careful governance, costs can rise unpredictably, vulnerabilities can go unnoticed, and compliance can be put at risk.
This was the situation faced by a London-based financial services provider relying on AWS for mission-critical operations. With legacy systems, aged credentials, and limited visibility into workloads, the company needed clarity and a path to optimization.
Through an AWS Well-Architected Framework Review (WAFR), grounded in the five AWS Well-Architected Framework pillars — security, reliability, cost optimization, operational excellence, and performance efficiency — Perfsys identified hidden risks, unlocked cost savings, and helped the client strengthen both security and operational efficiency.
About the Client
Company Name: Financial Services Company (Confidential)
Founded: 2010
Headquarters: London, United Kingdom
Industry: Financial Services / Fintech (Foreign Exchange, International Payments, Treasury Risk Management)
Company Size: 11–50 employees
Background
A London-based financial services company provides foreign exchange services to corporates and private clients. Operating in a sector where trust, compliance, and efficiency are non-negotiable, the company depends heavily on AWS infrastructure to run its core services.
But due to staff changes and accumulated legacy systems, the client found themselves in a challenging situation:
- Nobody had a complete picture of how the AWS environment was structured.
- AWS bills were growing unpredictably, without clear explanations.
- Concerns were raised about whether the setup was secure and aligned with best practices.
With compliance, costs, and security at stake, the company turned to Perfsys for help.
The Challenge
The client's leadership team needed confidence that their AWS environment was well-managed, cost-effective, and secure. Key challenges included:
1. Visibility Gap
- Multiple workloads were running, but with little documentation or centralized understanding.
- Legacy maintenance from former staff created "black box" systems.
2. Cost Concerns
- AWS bills were rising, but stakeholders lacked a clear understanding of which resources or services were responsible.
3. Security & Compliance Risks
- Aged IAM credentials (one access key active for 1198 days).
- Deprecated Lambda runtimes (Node.js 14/16, Python 3.8).
- Lack of automated credential audits or vulnerability management.
4. Reliability Gaps
- RDS backups not encrypted.
- Service quotas not actively monitored, risking sudden outages.
- Some Lambda functions with timeouts set to 900 seconds, leading to potential inefficiencies and risks.
Our Approach
To give the client clarity and confidence, Perfsys recommended an AWS Well-Architected Framework Review (WAFR) — a structured audit across the AWS Well-Architected Framework pillars, focusing on security, reliability, and cost optimization.
Step 1: Structured Review
- Evaluated 24 of 57 Well-Architected questions, focusing on security, reliability, and cost optimization.
- Collected data from AWS Well-Architected Tool, Inspector, and Trusted Advisor.
Step 2: Vulnerability Scanning
- Performed a deep-dive with Amazon Inspector, uncovering 20+ critical vulnerabilities, including remote code execution flaws in Windows and Chromium.
- Created a risk map to prioritize fixes based on exploitability and business impact.
Amazon Inspector – Critical Findings by Workload
Amazon Inspector – Findings Overview and Remediation Paths
Step 3: Immediate Remediation
- Security: Rotated long-lived IAM credentials, enabled IAM Access Analyzer, and implemented vulnerability management workflows.
- Compute & Costs: Enabled AWS Compute Optimizer to identify under- and over-provisioned resources. The analysis revealed rightsizing opportunities in ECS services on Fargate, with an estimated 41% monthly savings ($16.99 USD) if optimized.
- Reliability: Recommended encryption for RDS backups, activated Trusted Advisor quota alerts, and identified reliability risks in Lambda configurations.
Step 4: Additional Recommendations
- Upgrade Lambda runtimes to supported versions.
- Require EC2 IMDSv2 for stronger instance metadata security.
- Fix FSx domain connectivity issues with Microsoft AD.
- Enable AMI deregistration protection to prevent accidental deletions.
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Results
As a direct outcome of the AWS Well-Architected Framework Review , the client secured $5,000 in AWS credits, improved compliance, and gained clear visibility into future cost optimization opportunities.
- Improved cloud security posture, validated by vulnerability scanning and IAM hardening.
- Clear cost optimization path: Compute Optimizer surfaced 41% potential savings on ECS Fargate workloads.
- Compliance alignment: stronger credential management, encryption of backups, and proactive quota monitoring.
- Confidence restored: the client's leadership gained full visibility into how their infrastructure worked and how to manage it going forward.
Client Feedback
The CTO shared their experience in a verified Clutch review :
"The team was very methodical and delivered within their set timelines. Thanks to Perfsys’ efforts, we were able to improve our cloud security posture and solve existing issues. The efficiency and expertise they demonstrated were impressive."
— CTO, Financial Services Company, London (Clutch Review, Feb 2025)
The client awarded Perfsys 5.0 out of 5 across all categories: quality, schedule, cost, and willingness to refer.
Conclusion
This project illustrates how Perfsys helps organizations facing staff changes, legacy complexity, and rising AWS costs. By applying the AWS Well-Architected Framework Review, we:
- Exposed and remediated hidden risks.
- Brought clarity to cloud operations.
- Unlocked financial credits and cost optimization opportunities.
- Built a roadmap for secure, compliant, and resilient AWS operations.
This case study demonstrates how an AWS Well-Architected Framework Review helps financial services organizations transform uncertainty into confidence, while aligning with the AWS Well-Architected Framework pillars of cost optimization, security, and reliability.
FAQ
Eugene Orlovsky
CEO & Founder | Serverless architect with 10+ years of hands-on experience designing cloud-native architectures on AWS, backed by multiple AWS certifications. He is writing bridges deep technical expertise with real-world business strategy, covering topics from AWS best practices to scaling tech-driven organizations.
