# Sonal Ramnani > Principal Software Engineer | Platform Leadership | Distributed Systems, Cloud & Security | Big Data Location: San Jose, California, United States Profile: https://flows.cv/sonalramnani Technical Leader specializing in architecting large scale distributed systems and multi-tenant cloud applications at massive scale. Proven track record of engineering mission-critical services. Expert in Java Spring Boot, Big Data analytics (ADX/KQL), and SRE principles (SLIs/SLOs) to drive 99.9% system reliability and executive-level business value. Fed clearance. ## Work Experience ### Principal Software Engineer @ Zscaler Jan 2019 – Present • Scaled and managed the Call Quality Monitoring (CQM) service, a flagship ZDX feature highlighted in two consecutive CEO quarterly earnings calls as a top-5 strategic business driver. • Architected a high-performance Alert Notification Service that was adopted as the standardized alerting framework across multiple cross-functional engineering teams at Zscaler. • Architected and scaled distributed systems processing 20M+ events per day with sub-second latency • Leveraged ADX (Azure Data Exchange) and KQL (Kusto Query Language) to build complex, low-latency queries across BigData enabling real-time visualization (dashboards) of mission-critical telemetry. • Strengthened the resilience of Zscaler’s CQM service by implementing a robust observability framework. Using Prometheus and Grafana, I established SLI/SLO metrics necessary to maintain high-performance standards for 20M+ events per day. • Owner of CQM in Commercial, FedMod, FedHigh and IL5 (DoD) clouds. US Citizen with Federal clearance. • Spearheaded an Apache Flink-based streaming PoC on top of the existing infrastructure to modernize the alerting engine to improve the speed at which alerts were being processed. • Championed security-first architecture, implementing Zero Trust principles, OAuth, and TLS across platform services • Mentored senior engineers, drove technical standards, and influenced long-term platform strategy • Adopted AI-assisted engineering workflows to improve development velocity, design quality, test coverage and code review efficiency ### Technical Lead @ Aruba, a Hewlett Packard Enterprise company Jan 2018 – Jan 2019 ### Lead Software Engineer (Backend) @ CloudPassage Jan 2017 – Jan 2018 Lead for designing and implementing CSM (Configuration Software Monitoring) feature for servers running Docker and for Docker images on a customer's registry. Coded in Ruby and Golang. This SaaS application collects information from the customers’ servers and Docker images via an agent and analyses them on the cloud against publicly available standards. Worked as the dev. lead for this project. Received the Employee of the Quarter Award for Phase 1 of this project. ### Staff Software Engineer @ Infoblox Jan 2014 – Jan 2017 - Worked on DNS Firewall as a Service – Infoblox’s first SaaS offering – an AWS hosted DNS security solution that runs on Docker. Received Team of the Quarter Award for this. - Team lead for a team of 10 engineers that worked on integrating Infoblox’s NIOS solution with Cisco ISE. - Team lead for a team of 8 engineers that worked on integrating Microsoft AD user data with Infoblox’s NIOS solution. Received Employee of the Quarter Award for this. Both Cisco ISE Integration and Identity Mapping are mentioned as one of the 10 business highlights for Infoblox for FY 2016 (https://globenewswire.com/news-release/2016/08/31/868627/0/en/Infoblox-Reports-Fourth-Quarter-and-Fiscal-Year-2016-Results.html) ### Technical Leader @ Cisco Systems Jan 2013 – Jan 2014 | Bangalore, India Lead a team of 8 engineers doing a PoC for integrating different authentication mechanisms under Nginx acting as a frontend to Tomcat. - Successful PoC with a working demo in 3 months. - Integrated username/password authentication using flat file, DB and OAuth authentication. - Inserted custom information in a custom header into the request forwarded by Nginx to Tomcat - Innovative solution using Nginx as a container for authentication. Led to Tomcat performance improvement without needing to change the webapps that Tomcat hosted. - In addition to acting as the team lead, actively participated in a 2 member sub-team working on sub-parts of the project. ### Sr. Software Engineer @ Cisco Systems Jan 2012 – Jan 2013 | Bangalore, India - Lead a team of 3 engineers to demonstrate a PoC for bringing up a CUCM on an OpenStack VM. Final product was a demo-able CUCM image with users configured that ran on an OpenStack VM on baremetal. Multiple CUCM images could be brought up and taken down using the Horizon dashboard from OpenStack. - Worked on integrating a Cisco SRST IOS router into the CUCMBE3K solution such that a backup communication mechanism was available in case IP connectivity between the sites or CUCMBE3K went down. This product was aimed at emerging countries with network availability issues, so a backup communication mechanism was a highly desired item. - Worked with architects to come up with a next-level design and architecture for supporting multiple different IOS routers with different connectivity protocols (e.g. FXO, SIP) with dialing transparency. ### Sr. Software Engineer @ Cisco Systems Jan 2001 – Jan 2011 - Worked on the design for VossSync for HCS - hosted collaboration solution for the service provider cloud. This took the configurations from VOSS via SOAP and used it to populate HCS database. Designed and implemented the building blocks of this project so the other team members could start working on it. - Designed and implemented the Whisper Coaching/Agent Greeting features in CUCM - a large enterprise unified collaboration product from Cisco. Worked as the SIP prime for these features. - Feature prime for Park Monitoring in CUCM. Responsible for the entire feature delivery. - Feature Prime for adding support for the new RT-Lite models phones in CUCM. - SIP prime for secure recording feature on the SIP Trunk. - Feature prime for adding conference support to the new SIP RT phones. - Designed and implemented the SIP and SIP TNP module in Camelot. With this support, Camelot became one of the primary tools used for CUCM testing. It supported both feature and stress testing. - Designed and implemented the H.323 module for Camelot. - Designed and implemented a common framework for video transmission over an RTP stream. - Implemented a unified file access framework for transmitting audio and video in the form of RTP packets - Designed and developed Percival. It allows users to generate their own ISDN Q.931 messages and to create their own Q.931 state machines, thus allowing users to script their own Q.931 protocol. It was extensively used for negative testing. ## Education ### Masters in Computer Science Virginia Tech ### Bachelor of Engineering (B.E.) in Computer Science University of Mumbai ## Contact & Social - LinkedIn: https://linkedin.com/in/sonalramnani --- Source: https://flows.cv/sonalramnani JSON Resume: https://flows.cv/sonalramnani/resume.json Last updated: 2026-04-12