Prithwiraj Das

Lead Software Engineer

Building distributed systems for fintech & capital markets.

Software engineering leader with 12+ years building cloud-native, transaction-heavy SaaS systems across fintech, capital markets, healthcare, and enterprise SaaS. Deep expertise in .NET/C#, event-driven architecture, messaging systems (RabbitMQ, SNS/SQS, SignalR), and AWS. Versatile across Python, Node.js/TypeScript, Angular, React, and Blazor Server, with experience across PostgreSQL, SQL Server, MongoDB, MySQL, Redshift, and data warehouse pipelines. Long-time adopter of AI-assisted development, enthusiastic about how Claude, Copilot, and agentic tooling reshape engineering, while bringing the engineering judgement that decides when they accelerate delivery and when they need correction.

Get in touch LinkedIn GitHub Greater Toronto Area, Canada
Portrait of Prithwiraj Das
Experience

Where I've built things.

Oct 2025 – Present

Lead Software Engineer

Derivative Path · Walnut Creek, CA (Remote)

Driving the migration of a legacy derivatives trading platform to modern cloud-native architecture on DerivativeEDGE. Working across the full distributed pipeline: trade entry, pricing, risk, and analytics.

  • Implemented distributed tracing (OpenTelemetry) across a multi-service pricing pipeline, identifying a ~300s latency bottleneck in the Analytics Pipeline and giving leadership actionable data to prioritize optimization.
  • Resolved migration-blocking defects affecting all DerivativePath client migrations: multi-tenant data isolation and reversed MTM/NPV pricing values.
  • Designed real-time status notification architecture using event sourcing (Marten) and messaging patterns (Rebus), replacing blind polling with live visibility for risk analysts.
  • Piloting a Kafka-based transactional outbox for cross-service messaging, moving the platform toward reliable, replayable event delivery.
  • Driving delivery of five Q2 roadmap epics spanning FX Options, CVA/DVA pricing, performance, and data warehouse migration, coordinating across product, analytics, and platform teams.
.NET 10C#Blazor ServerSignalRMartenRebusFastEndpointsPostgreSQLRabbitMQKafkaAWSOpenTelemetryDocker
Sep 2024 – Sep 2025

Software Development Team Lead

Snap-On (Dealer-FX) · Toronto, ON

Led two product teams on the Dealer-FX One Platform, a cloud-native SaaS suite for automotive OEMs and dealerships.

  • Led GM My Rewards integration, managing core team and contractors, securing Dealer-FX as GM's preferred vendor.
  • Built and deployed APIs using AWS SAM-based Node.js with Sequelize ORM for Purchase Order and Parts Inventory.
  • Stabilized release quality and delivery cadence, reduced hotfixes and bug escape rates, improved sprint throughput.
  • Managed a team of 4 developers and 2 QA engineers, reducing hotfixes by 60-70% and bug escape rates by 70-80%, with sprint throughput up 20-30%.
.NET Core 8Node.jsSequelizeAWS LambdaAWS SAMPostgreSQLRedisAngular 16/17GitHub ActionsDocker
Apr 2023 – Sep 2024

Software Engineering Team Lead

EverCommerce (Service Fusion) · Toronto, ON

Led Service Fusion SaaS platform rewrite from monolith to microservices using Ardalis Clean Architecture. Managed a team of 4.

  • Delivered 10DLC messaging compliance transformation within a 2-month deadline, one of the first features shipped on the rewritten architecture, supporting ~600 messages/day for initial clients.
  • Supported data warehouse initiative via Decodable and AWS Lambda, then led delivery of the reporting microservice to early adopters within 2 months.
  • Standardized microservices patterns across a 4-engineer team spanning ~10 microservices, updating project templates and AWS CodeArtifact package management.
.NET Core 7C#MySQLAWSArdalis Clean ArchitectureDecodableDockerxUnit
May 2022 – Apr 2023

Senior Software Engineer

BeyondTrust · Halifax, NS (Remote)

Contributed to the Endpoint Privilege Management (EPM) product suite, bringing microservices experience as the department transitioned to cloud-native architecture.

  • Delivered key microservices for the EPM platform and contributed to migrating a legacy product to a multi-tenant SaaS model.
  • Stepped up to support the DevOps team in migrating from Azure DevOps to GitHub, redesigning 14 CI/CD pipelines across Terraform and Kubernetes.
.NET Core 6/7PostgreSQLElasticsearchAWSAzureGitHub ActionsDockerKubernetes
May 2021 – May 2022

Senior/Lead Backend Developer

Paige AI (via Velocity Global) · Toronto, ON / Contract

Led backend development for the FullFocus Viewer, an AI-powered digital pathology platform. Oversaw API design, deployment, and cross-team integration.

  • Led the rewrite of FullFocus Viewer backend to .NET 6 across 3 microservices, serving ~50 pathologists, introducing new APIs for product integration.
  • Built 3 microservices in Python (Flask) for new capabilities and audit trails required for FDA certification.
  • Played a key role in achieving FDA certification, the first FDA-cleared AI-powered digital pathology platform for primary diagnosis.
.NET Core 5/6PythonAWSPostgreSQLMongoDBRedisKubernetesDataDogGitLab CI
Aug 2019 – May 2021

Senior/Lead Software Engineer

Affirm (PayBright) · Toronto, ON

Joined PayBright as Senior Developer, grew into Lead Engineering role during rapid scale (13 to 45 engineers). Contributed to hiring, mentoring, and drove foundational changes to development process before acquisition by Affirm.

  • Led Core Loan Systems rewrite into .NET Core microservices, including domain discovery and POC work shaping next-gen architecture.
  • Transformed database development workflow with Redgate SQL, reducing deployment time from days to hours via automated CI/CD pipelines.
  • Delivered key client integrations (Samsung Canada, Apple Canada), contributing to market dominance and eventual acquisition by Affirm.
  • Built ETL/ELT workflows using Python, Azure Data Factory, and Node.js. Created BI dashboards on Looker for stakeholders.
.NET CoreC#SQL ServerMongoDBNode.jsPythonAzure Data FactoryRedgate SQLDockerLooker
Nov 2018 – Aug 2019

Dynamics CRM/.NET Developer

Cineplex Entertainment · Toronto, ON

Built features for the Corporate Fulfillment platform, a CRM and web application for Cineplex gift card sales and distribution.

.NETDynamics CRM 2016C#SQL ServerAgility CMSWCF
Nov 2017 – Nov 2018

Senior Software Developer

Fleet Complete · Toronto, ON · Contract

Modernized Courier Complete from VB6 desktop to web using REST APIs and Angular 6. Represented Fleet Complete at the AT&T IoT Civic Hackathon.

.NETAngular 6.NET CoreWeb API 2MVC 5SQL Server
Jun 2017 – Nov 2017

Senior Software Developer

Condo Control Central · Toronto, ON · Contract

Developed features for the property management SaaS platform. Built a Status Certificate portal for condo unit owners.

.NETC#MVC 3SQL ServerDevExpress
May 2015 – Jun 2017

Software Developer

Advanced Utility Systems · Toronto, ON

Key member of the CIS Infinity billing platform team. Led the Infinity.Link V4 portal rewrite on DotNetNuke. AODA compliance work enabled City of Ottawa to sign a $3M contract, the company's largest acquisition in 2016.

.NETDotNetNukeSQL ServerBootstrap 3REST APIWCAG 2.0
Jul 2014 – Apr 2015

IT Consultant

Dapasoft Inc · Toronto, ON

Delivered .NET web applications, Dynamics CRM integrations, and data migration solutions across client projects including OFIFC, Bell Fund (Bell Canada), and DATIS.

.NETDynamics CRM 2013SQL ServerTelerik UIXRM Framework
Nov 2013 – Apr 2014

Software Developer (Internship)

AMA Inc · Mississauga, ON

Built a Wi-Fi marketing portal for retail locations. Presented at a CBC News showcase event, resulting in 3 client sign-ups including Shoppers Drug Mart.

.NETC#PHPLinux
Technical skills

What I work with.

Languages & Frameworks

C#, .NET 10, ASP.NET, Blazor Server, Python, Node.js/TypeScript, SQL, Angular, React, SignalR

Cloud & Infrastructure

AWS (Lambda, S3, EC2, EKS, SAM, SNS/SQS), Azure (AD, DevOps, SQL), Docker, Kubernetes, Terraform

Architecture & Patterns

Microservices, Event Sourcing (Marten), CQRS, Clean Architecture, FastEndpoints, Rebus, OpenTelemetry

Databases & Data

PostgreSQL, SQL Server, MongoDB, MySQL, Redis, Redshift, Kafka, ETL/ELT (Azure Data Factory, Decodable)

DevOps & CI/CD

GitHub Actions, GitLab CI, Bitbucket Pipelines, Redgate SQL

Leadership

Team leadership (4 to 6 engineers), architecture ownership, code review, sprint execution, cross-functional delivery, mentoring

AI-Assisted Engineering

Claude Code, GitHub Copilot, MCP (Model Context Protocol), Semantic Kernel, Ollama, RAG, spec-driven development

Projects & open source

Side work & explorations.

Showcase

WorkerSagaDemo

Distributed saga orchestration with AI trade classification. Rebus sagas, transactional outbox, Semantic Kernel + Ollama, SignalR real-time UI, .NET Aspire, OpenTelemetry custom spans.

View on GitHub Showcase

ServiceTrackr

Secure .NET 9 Web API with clean architecture, JWT auth with refresh tokens, PostgreSQL with EF Core, Redis caching, Docker-ready.

View on GitHub In progress

dotnet-marten-starter

Reference implementation for event sourcing and CQRS with Marten on PostgreSQL.

View on GitHub Reference

dotnet-architecture-decisions

Architecture decision records and notes on distributed .NET. Outbox, sagas, observability, and the tradeoffs behind them.

View on GitHub Reference

dotnet-otel-cookbook

Practical OpenTelemetry recipes for .NET. Custom spans, metrics, and traces across messaging, sagas, and AI calls.

View on GitHub Planned

ContextForge

AI context platform exploring RAG fundamentals, polyglot storage, and MCP integration.

View on GitHub
Writing

Technical articles.

2026

The bugs were never in the new code

Adding one feature to a live multi-tenant system surfaced three stacked bugs, all rooted in the old code's unwritten assumptions rather than the new code itself.

Read on Medium April 2026

Feature flags are not a free lunch

What I learned about the hidden cost of feature flags after migrating between flag providers in production, and why treating them as free switches leads to real problems.

Read on Medium April 2026

What goes wrong when you switch branching strategies mid-flight

Lessons from switching branching strategies on an active codebase. What broke, what worked, and what I would do differently next time.

Read on Medium March 2026

What broke my JWT flow in Blazor Server and how I fixed it

Three issues I hit in production with HttpContext, token caching, and IHttpClientFactory handler pooling. Here is what fixed each one.

Read on Medium
Highlights

Notable achievements

  • Achieved FDA certification for FullFocus Viewer, the first FDA-cleared AI-powered digital pathology platform for primary diagnosis.
  • Led the GM MyRewards integration at Snap-On (Dealer-FX), securing preferred vendor status across all GM dealerships in North America.
  • Represented Fleet Complete at the AT&T IoT Civic Hackathon in Indianapolis.
  • Delivered a $3M project for City of Ottawa in 2016, leading to promotion.
  • Presented a marketing product at a CBC News showcase; purchased by Shoppers Drug Mart and two other companies.
Education & certifications

Academic background

  • Post Graduate Diploma, Information TechnologyHumber Institute of Technology and Advanced Learning, Toronto2012 – 2014
  • B.Tech, Electrical EngineeringWest Bengal University of Technology, India2009 – 2012
  • Diploma in Electrical EngineeringRamakrishna Mission Shilpapitha College / WBSCTE, India2006 – 2009
Microsoft Certified: Azure Fundamentals (2020) AWS Certified AI Practitioner (In Progress, 2026)
Get in touch

Let's connect.

+1 (647) 705-6210 linkedin.com/in/prithwirajdas github.com/prithwirajdas007 Greater Toronto Area, Canada