Varun Kumar, Developer in Toronto, ON, Canada
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Varun Kumar

Verified Expert  in Engineering

Integration Developer

Toronto, ON, Canada
Toptal Member Since
September 11, 2020

Varun is a senior middleware integration developer with several years of extensive, hands-on experience working with integration tools such as MuleSoft and webMethods, including being a certified MuleSoft developer. Varun has used these tools to integrate with several apps that run on Salesforce, SAP, APTOS (merchandising system), order management system (IBM Sterling), and Workday across domains such as retail, utility, banking, aviation, and automobile.


Commonwealth Financial Network
SQL, Azure, Enterprise Architecture, Solution Architecture, APIs...
City National Bank
Azure Key Vault, Redis Cache, DevOps, MuleSoft, DataWeave, Anypoint Studio
Air Canada
Mule ESB, MuleSoft, Anypoint Studio




Preferred Environment

Oracle, SQL, JSON, RAML, API Integration, REST, SOAP, APIs, webMethods, Mule Runtime Engine, Mule ESB, MuleSoft

The most amazing...

...thing I've developed is a university website where students can enroll by selecting their respective courses.

Work Experience

Solutions Architect

2021 - 2023
Commonwealth Financial Network
  • Developed the affiliates APIs that integrate between A360 advisor services and common wealth network.
  • Developed a common logging framework that is used across all the APIs across CFN.
  • Successfully deployed multiple APIs to production.
  • Developed an error-handling framework that has been added to all CFN APIs.
Technologies: SQL, Azure, Enterprise Architecture, Solution Architecture, APIs, Software Architecture, Data Engineering, ETL, Databases, Database Security, DataWeave, Anypoint Studio

Senior Integration Developer

2019 - 2020
City National Bank
  • Developed APIs for a mobile application along with integrating banking systems such as FIS (Fidelity National Information Services) and TSYS (Total System Services).
  • Implemented APIs using API-led connectivity and various MuleSoft product stacks like Designer, Exchange, API Gateway, and so on.
  • Implemented a caching mechanism to improve the performance of the applications.
  • Collaborated with enterprise architects and IT program managers to enhance existing business applications and facilitate solutions to meet business requirements.
  • Developed mobile-based applications and integrated them with enterprise products.
  • Developed mobile banking applications such as banking accounts, creation of payments, creation of payees, credit card transactions, and login credentials validation against ISAM.
Technologies: Azure Key Vault, Redis Cache, DevOps, MuleSoft, DataWeave, Anypoint Studio

Senior Integration Developer

2019 - 2019
Air Canada
  • Developed REST APIs using the MuleSoft Anypoint API Platform.
  • Contributed to the API design sessions to decide the various resources within each API, message schemas, message formats, and authentication.
  • Created Mule flows using endpoint connectors and components using Mule ESB to integrate client/server systems.
  • Identified, analyzed, and developed interfaces and integration flows using the Mule ESB Anypoint platform including Mule runtime and connectors.
Technologies: Mule ESB, MuleSoft, Anypoint Studio

Senior Integration Developer

2018 - 2018
Tory Burch
  • Designed and developed enterprise services using RAML and REST-based APIs and used various transformers in Mule ESB based on the use case along with implementing custom transformations.
  • Worked on various EDI (ANSI X12) standards, IDOC standards, XML messages, and SAP IDOCs.
  • Designed integration solutions for the database (Oracle) to SAP (S4).
  • Configured WM Adapters like SAP, JDBC, Siebel (basics), XML, flat files, and more.
  • Implemented EAI projects involving various line-of-business applications, SAP, B2B partners, and databases like Oracle.
Technologies: webMethods, APIs, MuleSoft, Anypoint Studio

Senior Integration Developer

2017 - 2018
  • Created deliverables according to the software development lifecycle such as functional and technical specifications, use cases, test cases, test results, among others.
  • Extensively used WebSphere MQ adapters to perform MQ operations and JDBC adapters to connect to the DB2/Oracle database.
  • Built interfaces for inbound and outbound EDI transactions such as invoice (880), purchase orders (850), product distribution (867), 820, 830, 888, 410, and more.
  • Created high-level design documents, solution-specific design documents, business requirement solutions, technical documentation, and mapping specification documents.
Technologies: webMethods, Salesforce, MuleSoft

Integration Developer

2015 - 2017
  • Designed and developed custom interfaces using webMethods.
  • Managed Installations and configurations of webMethods Integration Server, Broker Server, and My webMethods Server.
  • Created flat-file dictionaries along with the corresponding schemas and installed EDI schemas for both trading networks and IS usage, XML schemas, required documents, flow services, Java-based utilities, and helper servers required.
  • Designed the IVR call flow and call center integration for an end-to-end application.
Technologies: webMethods, Web Services, SOAP, REST, APIs

Integration Developer

2014 - 2015
  • Created a trading network component like a partner profile document type, processing rules, and TPA.
  • Mapped inbound EDI documents to flat files, XML, and outbound IDOCs to EDI using wmEDI and wmEdiForTN packages.
  • Wrote customized flow services to send outbound documents such as invoices and shipment notices.
  • Created a customized partner profile under MWS by identifying each partner and transactions in the trading networks.
  • Developed B2B applications with the 9.5 version and also built integrations using a pub-sub pattern.
Technologies: Web Services, EDIFACT, XML, APIs, webMethods

Student Course Enrollment Application

This application allows students to enroll in classes and also provides several online courses to individuals who are interested in learning programming languages. Users can attend classes from home rather than going to the training institute.
2013 - 2014

Master's Degree in Computer and Information Systems

University of Central Missouri - Warrensburg, MO, United States

APRIL 2020 - APRIL 2022

MuleSoft Certified Developer



MuleSoft Certified Developer — Integration and API Associate Mule (3.9)



Java SE 6 Programmer



Anypoint Studio, Adobe Experience Manager (AEM), Azure Key Vault




MuleSoft, Mule ESB, Mule Runtime Engine, webMethods, Oracle, Salesforce, Azure


SQL, Web Services Description Language (WSDL), PHP, XML


JSON, Redis Cache, Databases, Database Security

Industry Expertise

Project Management


APIs, API Integration, DataWeave, Integration, Web Services, SOAP, RAML, Scripted Animation (JavaScript), EDIFACT, Web Methods, Enterprise Architecture, Solution Architecture, Software Architecture, Data Engineering

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