Shan Wijenayaka

Lead AI/ML Engineer

AI Platform & Security Operations

Joined to build Certis's AI platform from the ground up - designing and shipping a multi-service system spanning real-time voice AI, computer vision, and centralized model governance for enterprise security operations.

• Built a real-time Voice AI pipeline (STT, agent orchestration, TTS) with safety guardrails and human handoff, achieving p95 latency under 600ms at production scale
• Shipped computer vision workflows for operational triage - inference services, audited pipelines, and human-in-the-loop review - replacing manual incident classification
• Defined the platform architecture, grew the team through hands-on hiring, and set engineering standards - enabling the team to ship voice AI and CV services to production independently

Senior Software Engineer

Regulatory Intelligence Platform

Sole architect on a production LLM-powered regulatory platform enabling search and Q&A over 1M+ regulatory documents, owning the full stack from retrieval pipeline to deployment.

• Built evaluation and regression harnesses that gated every deployment, catching answer-quality regressions before they reached production in a compliance-critical environment
• Diagnosed reliability bottlenecks through targeted instrumentation, improving uptime from ~99.5% to ~99.95% and reducing error rates by ~20%
• Right-sized compute and tuned auto-scaling policies, cutting cloud spend by ~35% with zero SLA regressions

Senior Software Engineer

Derivatives Trading Systems

Replaced legacy batch-oriented trade processing with low-latency event-driven microservices in Go at the world's largest interdealer broker, with strict consistency and ordering guarantees across OTC derivatives.

• Designed the trade processing pipeline end-to-end, handling ~35k trades/day at sub-100ms service-level latency for interest rate and currency swap instruments
• Led zero-downtime migration of 12+ services from Java/MSSQL to AWS-native stack (Kafka/MSK, DynamoDB Streams, Aurora PostgreSQL), choosing incremental extraction over big-bang cutover to maintain zero trading interruptions throughout
• Designed and integrated ML-based anomaly scoring into pre-clearing, building explainable flags that traders and operations could act on directly - reducing downstream breaks
• Instrumented the full service mesh with OpenTelemetry, cutting unknown tail-latency causes by ~40% and establishing SLI/SLO baselines for each service

Senior Software Engineer

Consumer Dining Platform

Modernized the backend of a high-traffic reservation platform, migrating from monolith to microservices while keeping real-time booking and availability flows running across APAC markets.

• Defined service boundaries, rate-limiting, and caching strategies that maintained latency SLAs under peak dinner-hour traffic spikes
• Built microservices for real-time restaurant availability, booking, and waitlist orchestration serving concurrent users across multiple markets
• Led monolith decomposition into independently deployable services, enabling per-team ownership and faster release cycles

Wiley Global Technology / Sysco LABS Sri Lanka / Omobio (Pvt) Ltd.

Progressed from associate to senior engineer across Sysco LABS (Sysco Corporation tech arm), Wiley, and Omobio. Built backend platforms across enterprise and telco domains, including a USSD platform from scratch for Robi Bangladesh reaching 37M+ subscribers.