Lav is available for hire
Hire LavLav Kumar Vishwakarma
Verified Expert in Engineering
Web Security Developer
Bhopal, Madhya Pradesh, India
Toptal member since June 24, 2022
Bio
Lav is a back-end and AI engineer with 10+ years of experience building scalable, distributed systems, now focused on taking AI agents from pilot to production. He scaled GrowthDay to 400,000+ users, shipped two production AI systems—a RAG coaching avatar and a crash-triage agent that opens pull requests—and built scheduling infrastructure used by Google and Telefónica. Acknowledged by 100+ companies for security research, he recently reported three vulnerabilities in AWS MCP servers.
Portfolio
UChicago Medicine
Adobe, Dashboard Development, Go, Adobe Analytics
Summit Health
Google Analytics, Google Analytics API, Google Tag Manager, JavaScript...
Independent Security & AI Researcher
Web Security, AI Security, Security, REST APIs, Vercel, Web App Security...
Experience
- Web Security - 7 years
- Back-end - 7 years
- REST - 7 years
- Go - 6 years
- PostgreSQL - 6 years
- Microservices - 5 years
- gRPC - 5 years
- Java - 4 years
Preferred Environment
Go, PostgreSQL, gRPC, REST, Microservices, Docker, Claude API, OpenAI API, LangGraph, AI Agents
The most amazing...
...things I've built are production AI agents serving 400,000+ users at GrowthDay and scheduling infrastructure used by Google and Telefónica.
Work Experience
Adobe Analytics Developer
2025 - PRESENT
UChicago Medicine
- Designed and built a HIPAA-compliant Customer Journey Analytics (Adobe CJA) pipeline for a major US academic health system, covering XDM schema design and a complete funnel event taxonomy across patient-facing web properties.
- Conducted a PHI audit of the analytics stack, identifying and remediating fields where protected health information could leak into collection, and defining governance rules to keep the pipeline compliant.
- Authored handoff documentation and trained the internal team, ensuring the pipeline remained maintainable after the engagement.
Technologies: Adobe, Dashboard Development, Go, Adobe Analytics
Google Analytics 4 Expert
2022 - PRESENT
Summit Health
- Architected Salesforce-driven personalization for a multi-state US healthcare network, connecting CRM data to on-site experiences while keeping PHI out of marketing systems.
- Designed and implemented marketing automation flows across web and CRM, replacing manual processes and previous tools and standardizing campaign event tracking.
- Set up BigQuery-based reporting connecting web analytics with CRM outcomes, giving marketing teams visibility into funnel performance and campaign attribution.
- Ensured privacy-compliant data collection across the stack, including consent management integration.
Technologies: Google Analytics, Google Analytics API, Google Tag Manager, JavaScript, Salesforce, BigQuery, Marketing Automation, CRM, ETL, Data Pipelines, Salesforce Agentforce
Independent Security & AI Researcher
2018 - PRESENT
Independent Security & AI Researcher
- Discovered CVE-2026-16584 in the AWS API MCP Server: a failed policy initialization could leave deny/gate rules unenforced. AWS credited my report, and I have two more CVEs pending disclosure.
- Authored memory-blackbox, an open-source append-only memory provenance layer that makes AI agent incidents reconstructable—what the agent knew, when, and why it acted.
- Acknowledged and rewarded by 100+ companies, including AT&T, Opera (Hall of Fame), Airwallex, Check24, and the University of Michigan for responsibly disclosed vulnerabilities, including critical findings exposing production systems.
- Conducted BLE/IoT security research into battery management systems, currently in responsible disclosure.
Technologies: Web Security, AI Security, Security, REST APIs, Vercel, Web App Security, Product Security, Mobile App Security
Lead Software Engineer
2021 - 2026
GrowthDay
- Oversaw the development of back-end application architecture and system design for a personal development platform that includes live coaching sessions to help 400,000 active users build confidence, develop good habits, and improve their lifestyles.
- Spearheaded the development of a new enterprise product to introduce the GowthDay brand to SMEs and help each client build successful teams, emphasizing good communication, fostering company culture, and driving efficiency at scale.
- Developed new platform features, including a video conferencing system, enabling collaborative learning and gift subscriptions to drive user growth.
- Collaborated with executive stakeholders and design, front-end, and product teams to define technical product requirements, determine product features, and streamline an overall development roadmap.
- Supervised hiring and training of a back-end development team and collaborated with cross-functional leaders to deliver multiple complex projects.
- Shipped Brendon AI, a retrieval-augmented (RAG) coaching avatar with an in-house feedback engine, serving the full 400,000+ user base.
- Built an internal AI agent that ingests crash reports, root-causes them, and opens pull requests with candidate fixes—sustaining over 99.99% crash-free sessions.
Technologies: Java, Spring Boot, Keycloak, OAuth 2, Stripe, Apple Pay, Amazon Web Services (AWS), Amazon Elastic Container Service (ECS), MongoDB, Microservices, REST, Kajabi, Jira, Miro, Sentry, Analytics, Architecture, SQL, APIs, Zapier, Back-end Development, Cloud Services, Python, RAG Pipelines, AI Agents, Claude API, OpenAI API, Automation, Full-stack Development, REST APIs, Zoom, Webhooks, System Architecture, TypeScript, Next.js
Back-end Engineer
2021 - 2021
GrowthDay
- Led the revamp of the back-end development by rebuilding the app's core pillars from scratch, improving development processes, optimizing the developer experience, and driving enhancements to enable reusability, security, and increased performance.
- Enhanced the API performance and made it production-ready by implementing notifications, error reporting, centralizing logging, scaling, improving the response time, and providing support for regulatory compliance.
- Contributed to different analytics platform integrations like the Facebook pixel, Mixpanel, Google Analytics, and AppsFlyer.
Technologies: Java, Spring Boot, MongoDB, Keycloak, Miro, Amazon Web Services (AWS), Amazon Elastic Container Service (ECS), OAuth 2, REST, Analytics, SQL, APIs, Zapier, Google Analytics, Back-end Development, Cloud Services, REST APIs
Lead Software Engineer
2019 - 2021
Appointy
- Led the development of SaaStack, a SaaS platform, including designing the plug-and-play architecture for the back end with inbuilt scaling, security, and regulatory compliance handling.
- Contributed to core architecture layers, including authentication, roles and rights, licensing, logging, tracing, and scalability.
- Developed new features for SaaStack to support people, account, client billing, and enterprise management using Go, GraphQL, gRPC, and PostgreSQL.
- Enhanced performance, reducing the API response times from two seconds to less than 150 milliseconds.
- Assisted with the scaffolding app's command-line interface tools by leveraging Relay as a GraphQL client to eliminate the codebase set-up time and leveraging a protocol buffer to generate the Go service codebase.
- Decreased development time and maximized development flexibility by developing a set of code generation tools based on easy-to-use annotations and reduced the development time by 80% of code generation.
- Created guides and checklists for developers, worked on improving developer experience, and mentored developers to increase their efficiency.
Technologies: Go, Microservices, gRPC, REST, Protobuf, Docker, Kubernetes, PostgreSQL, MongoDB, SQL Server 2016, WebSockets, GraphQL, JSON Web Tokens (JWT), Hydra, OAuth 2, Web Architecture, NATS, Google Cloud Platform (GCP), Azure, Git, GoLand, Jira, Documentation, Payment APIs, Stripe, Square, Authorize.net, Zoho, SQL, APIs, Zoho CRM, Zapier, Microsoft Excel, Airtable, Google Analytics, Back-end Development, Customer Relationship Management (CRM), Cloud Services, Email Automation, Webhooks, PostGIS
Product Developer
2017 - 2019
Appointy
- Developed Appointy's small-to-large business scheduling tool based on microservice architecture. The tool is used by one million people.
- Evaluated integration libraries and tools to shorten the development time from one year to one month. Designed microservices and the micro front-end architecture to help further optimize development.
- Advised and oversaw client development by creating user flows, product roadmaps, and features with a team of eight back-end developers.
- Created a new product that coordinated fitness classes, restaurants, and spa scheduling for Google.
- Built a room conference scheduling system for Telefonica, one of Spain's largest telecom companies, with features for managing rooms, scheduling calendars, staffing, and CMS and TMS integrations.
Technologies: C#, IIS, SQL Server 2016, Azure, Docker, REST, Microservices, OAuth, Stripe, Square, Authorize.net, PayPal, Mixpanel, WebSockets, TMS, .NET 5, .NET Core, Go, PostgreSQL, Kubernetes, Web Security, SQL, APIs, Zapier, Microsoft Excel, Airtable, Back-end Development, Customer Relationship Management (CRM), Cloud Services
Associate Product Developer
2015 - 2017
Appointy
- Integrated a stripe payment system for accepting recurring and one-time payments and created a payment monitoring system to track and manage payments.
- Worked on the spam email checker script, which verified the existence of emails and reduced the email bounce rate by 99.9%.
- Reviewed system implementation for getting more reviews from the customers and increased the review ratio by 40%.
Technologies: Stripe, Node.js, Bash Script, REST, HTML, CSS, JavaScript, Zapier, System Implementation
Experience
Conferencing Portal for Telefonica
Designed the conference scheduling and management portal from scratch and communicated and collaborated with Telefonica's Madrid team. In addition, I worked on technologies including .NET Web API 2 and microservices. The project was integrated with CMS and TMS Cisco technologies and LDAP.
GrowthDay App
http://www.growthday.comCollaborated on GrowthDay, the world's first all-in-one personal development app. It empowers people in 190 countries and encourages them to use the tools, content, coaching, and community to grow and achieve their dreams. The app features live weekly training sessions by the world's best coaches and custom personal growth tools for journaling, online challenges, goal setting, habit scoring, life assessments, and community participation.
Appointy X
I developed the back-end architecture, built basic apps, and created various components for the team. Appointy X is a web-based SaaS product for scheduling classes, appointments, events, and meetings. This newer version based on SaaStack was written in a different stack from the ground up.
SaaStack
https://saastack.ioLed the development of SaaStack, a SaaS platform, and designed the plug-and-play architecture for the back end with inbuilt scaling, security, and regulatory compliance handling. In addition, I contributed to the architecture core layers, including authentication, roles and rights, licensing, and default libraries.
Appointy 9
I headed the entire back-end development for a web-based SaaS product for scheduling classes, appointments, events, meetings, and rooms. The project included selecting technologies for creating modular architecture and writing more than 90% of the back-end code. The product's components are used by Google and Telefonica.
Brendon AI — RAG Coaching Avatar (Growthday.com)
I built an AI coaching avatar of the company founder: retrieval-augmented generation over his complete body of work, plus an in-house feedback engine tuning response quality.
I owned retrieval design, grounding, and the evaluation loop, serving 400,000+ users.
I owned retrieval design, grounding, and the evaluation loop, serving 400,000+ users.
Crash-triage AI Agent
An internal autonomous agent that ingests production crash reports, clusters and root-causes them, and opens pull requests with candidate fixes—closing the loop from error signal to patch and helping sustain over 99.99% crash-free sessions.
memory-blackbox
https://github.com/lavkumarv/memory-blackboxOpen-source append-only memory provenance for AI agents: every memory write is a node, every read an edge, nothing mutated—making agent incidents reconstructable: what the agent knew, when it knew it, and why it acted.
Education
2019 - 2021
Master's Degree in Cyber Security
Rajiv Gandhi Proudyogiki Vishwavidyalaya - India
2013 - 2017
Bachelor's Degree in Computer Science
University Institute of Technology, RGPV - Bhopal, India
Certifications
JULY 2026 - JULY 2027
Claude Certified Architect - Foundations (CCA-F)
Anthropic
DECEMBER 2018 - JANUARY 2021
Certified Ethical Hacker (CEH)
EC-Council
Skills
Libraries/APIs
Node.js, Protobuf, Stripe, Stripe API, REST APIs, Authorize.net, Mixpanel API, Twilio API, Pushwoosh, Web API 2, Claude API, OpenAI API, Google Analytics API
Tools
GoLand, Git, Jira, IntelliJ IDEA, Sentry, Zapier, Microsoft Excel, RabbitMQ, NGINX, Miro, Keycloak, OneSignal, Jenkins, Google Analytics, ChatGPT, Zoom, Istio, Amazon Elastic Container Service (ECS), BigQuery, Adobe, Adobe Analytics
Languages
Go, Java, GraphQL, HTML, SQL, TypeScript, C#, CSS, JavaScript, Bash Script, Python
Frameworks
OAuth 2, gRPC, JSON Web Tokens (JWT), Spring Boot, Express.js, Next.js, Hydra, .NET 5, .NET Core, LangGraph
Paradigms
REST, Microservices, Serverless Architecture, Automation, ETL, Web Architecture
Platforms
Google Cloud Platform (GCP), Software Design Patterns, Kajabi, Docker, Azure, Amazon Web Services (AWS), Windows Server, Linux, Zoho CRM, LearnWorlds, Vercel, Kubernetes, Mixpanel, MacOS, Salesforce, Salesforce Agentforce
Storage
PostgreSQL, SQL Server 2017, MongoDB, Redis, MySQL, Memcached, Elasticsearch, Azure Active Directory, SQL Server 2016, Data Pipelines, PostGIS
Other
Software Development, Web Security, WebSockets, NATS, Server Security, Cloud Security, Development, Architecture, Documentation, Payment APIs, Web Server (IIS), Software as a Service (SaaS), Identity Server, Back-end, Zoho, APIs, Back-end Development, Cloud Services, Full-stack Development, Email Automation, Webhooks, Sharding, LDAP, Domain-driven Design (DDD), Telemetry, Load Balancers, Square, Apple Pay, TMS, Analytics, SAML-auth, Scalable Architecture, Maps, Airtable, Customer Relationship Management (CRM), System Architecture, Infrastructure Security, IIS 7, ECS, IIS, OAuth, PayPal, System Implementation, Security, AI Agents, Agentic AI, LLM Integration, RAG Pipelines, Google Tag Manager, Marketing Automation, CRM, Dashboard Development, AI Security, Web App Security, Product Security, Mobile App Security
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