Enterprise API Integration Architecture & E-Commerce Migration
Redesigned the integration layer for a major e-commerce platform at TCS — migrating from legacy middleware to cloud-based APIs using MuleSoft, Apigee, and IBM API Connect — improving system reliability and reducing operational costs by 40%.
IT Analyst – Digital Integration & Cloud Solutions · TCS
2016–2020
The Problem
A large e-commerce client was running on a fragile legacy middleware architecture that couldn't scale with traffic growth, required costly vendor maintenance, and created bottlenecks for new feature integrations. API governance was inconsistent across teams, creating security and reliability risks.
My Role
Owned the API design standards, governance framework, and migration sequencing strategy. I defined the phased rollout plan, authored the API lifecycle policy, and led the self-service catalogue design. Integration engineers owned implementation; I was the architecture and governance layer across the programme.
Discovery & Research
Audited the existing middleware topology across 80+ integration endpoints. Ran stakeholder sessions with platform, operations, and downstream engineering teams to map integration dependencies and risk. Identified the 20% of integrations that generated 80% of incident volume — these became the priority migration targets.
The Approach
Designed the end-to-end API management and governance layer, including security policies, lifecycle management, and integration reliability standards. Led the migration from legacy ESB-based middleware to a cloud-native API architecture using MuleSoft for integration orchestration and Apigee for API gateway and governance. Defined API standards, versioning policies, and rate limiting frameworks adopted across the client's engineering organization.
Key Decisions
Phased migration starting with non-critical integrations — this let us validate the new architecture and build team confidence before migrating the high-traffic, revenue-critical endpoints.
Built a self-service API catalogue instead of routing all onboarding through the integration team — this was a forcing function to write good documentation and was the primary driver of the 3× faster downstream integration metric.
Architecture / System Design
Structured the migration in phases — starting with non-critical integrations to validate the new architecture, then systematically migrating high-traffic, business-critical APIs. Applied event-driven patterns for order processing and inventory synchronization to replace tightly coupled synchronous calls. Built a self-service API catalogue enabling internal teams to discover, onboard, and monitor APIs without dependency on a central integration team.
What I'd Do Differently
I'd have invested more in internal developer experience tooling earlier — the migration unlocked speed, but teams still hit friction onboarding to new APIs because our documentation tooling lagged the actual API quality.
Outcomes
Reduced operational costs by 40% through elimination of legacy middleware licensing and reduced incident volume. Improved system reliability through standardised error handling and retry logic. Enabled downstream teams to integrate new services 3× faster using the self-service API catalogue.