Denis Treskunov

Education

1. Bachelor of Science, Mathematics

   01/2003 – 12/2006

   University of California · Berkeley, CA

   Computer Science Minor

Experience

1. Software Engineer, Principal

   04/2020 – Present

   Salesforce · Seattle, WA

   • Implemented support for Multi-factor Authentication (MFA) for signing in to Tableau Online.

   • Developed EasySSL, a library for zero-downtime updates of server and client TLS certificates.

   • Led a major, 6-month refactoring project to improve reliability of the sign-in service to and reduce technical debt. The refactoring reduced the LoC (Lines of code), as well as Cognitive and Cyclomatic complexity, while resolving long-standing defects.

   • Created a middleware service to allow Tableau products to use Salesforce’s LLM / GenAI service.

2. Software Engineer, Staff

   10/2011 – 04/2020

   Tableau Software · Seattle, WA

   • Championed the Infrastructure as code (IaC) concept. Created a versioned, idempotent deployment service to deploy Tableau’s SaaS products and their dependencies. Technologies used: Puppet to manage dependencies and roll out services, and Rundeck to allow the Ops team to execute pre-defined runbooks from a web app.

   • Created the login page for Tableau Online handling ~800k daily users at 99.99% availability. This service supports authentication via SAML, OIDC, and Mutual TLS, and is distributed globally across multiple regions for performance and resiliency. Technologies used: Spring Boot, Cassandra, DynamoDB.

   • Migrated on-premise infrastructure into AWS. Created build pipelines for triggering deployments after code merges. Technologies used: Terraform, GitLab CI/CD.

   • Architected a live migration of the user database from an on-premise Cassandra cluster into DynamoDB. To validate the new schema, Java instrumentation was used to detect any differences between the two databases.

   • Refactored and upgraded SAML logic into a separate library, fixing 16k compile errors.

3. Software Development Engineer

   02/2008 – 10/2011

   Amazon · Seattle, WA

   • Implemented a bytecode-level record/replay framework that was used by the team for regression testing against captured production data. The framework enabled nearly 100% code coverage for 22k lines of business logic.

   • Rewrote a Perl/Mason UI in Google Web Toolkit to resolve reliability, security and performance concerns. Eliminated page load fatals and reduced latency and bandwidth by 15x.

   • Participated in the design and implementation of a next-generation distributed workflow engine that was 3x more efficient than the engine it replaced, horizontally scalable, and multitenant.

   • Was involved in a multi-year effort to rearchitect and migrate 126k lines of C++ business logic to Java and to remove other legacy dependencies.

Skills

Interests