Publication
Don’t Build, Integrate: A Guide to CRM Integration
https://www.toptal.com/developers/crm/crm-api-integration-guide
Leif is currently unavailable
Leif Gensert
Verified Expert in Engineering
Software Developer
San Diego, CA, United States
Toptal member since February 14, 2018
Bio
For the past eleven years, Leif has worked as a full-time developer focusing on back-end development utilizing Ruby or Elixir. He's worked for giant consulting firms and newly founded startups. Through side projects and open source contributions, he makes sure he stays up to date on the latest tech. A healthy sense of pragmatism keeps him grounded to choose the technology that makes sense as opposed to going with whatever is hip right now.
Portfolio
Tata Steel DV
PostgreSQL, Heroku, Ruby
Blend Media
PostgreSQL, Elixir
QT Mobilitätsservice GmbH (Qixxit)
pgRouting, Docker, Neo4j, PostgreSQL, Elixir
Experience
- Ruby on Rails (RoR) - 9 years
- Ruby - 9 years
- PostgreSQL - 9 years
- REST - 5 years
- Java - 5 years
- Elixir - 4 years
- JavaScript - 3 years
- React - 3 years
Preferred Environment
Tmux, Git, Visual Studio Code (VS Code)
The most amazing...
...side project I've released is HN Vanity: an event-sourced application for getting basic hacker news statistics.
Work Experience
Developer
2018 - PRESENT
Tata Steel DV
- Scoped, planned and implemented new features to an internal application.
- Delivered a massive integration change with Zoho Books.
- Integrated Hubspot CRM.
Technologies: PostgreSQL, Heroku, Ruby
Developer
2018 - 2018
Blend Media
- Supported the development of new features.
- Came up with a new concept for the publishing pipeline of 360° videos.
- Successfully integrated the product with Salesforce Pardot.
Technologies: PostgreSQL, Elixir
Freelance Developer
2017 - 2017
QT Mobilitätsservice GmbH (Qixxit)
- Introduced a new CI pipeline to improve deployment processes and regression tests.
- Built an automated acceptance test suite to give product department a better overview of the state of development.
- Implemented a proof of concept for a routing engine based on pgRouting.
Technologies: pgRouting, Docker, Neo4j, PostgreSQL, Elixir
Freelance Developer
2016 - 2017
solarisBank AG
- Implemented a database anonymization program for efficiently creating test data.
- Improved the existing continuous integration process.
- Created a notifications feature in the core applications that sent out messages via WebHooks.
- Worked on a prototype for a core banking system built in a CQRS way.
Technologies: Docker, PostgreSQL, Apache Kafka, Elixir, Ruby
Senior Developer
2013 - 2016
Propertybase GmbH
- Designed and implemented a periodical import tool to fetch listing data in different formats (JRuby).
- Implemented and maintained the lead generation tool while working closely together with customer success and sales teams to further adapt the tool to new inbound channels.
- Handled and managed the technical onboarding of new clients (including data migration to Salesforce).
Technologies: Salesforce, Redis, MongoDB, PostgreSQL, JRuby, Ruby on Rails (RoR), Ruby
Senior Developer
2011 - 2013
stylefruits GmbH
- Maintained and improved the main application (Ruby on Rails).
- Developed a URL-shorting service (Sinatra on JRuby).
- Designed and implemented a back-end to manage language translation tokens (Sinatra).
- Managed and handled the weekly testing process—writing automated scripts and overseeing the manual testing sessions.
Technologies: MySQL, Redis, Ruby on Rails (RoR), Ruby
Senior Software Engineer
2008 - 2011
Capgemini
- Improved and maintained a Java-based web application for Deutsche Telekom AG (OMS-IP).
- Led workshop lessons regarding knowledge transfers for an offshore team in Kolkata, India.
- Maintained an invoicing system for a satellite TV provider in Munich.
- Improved an internal continuous integration workflow by dynamically dispatching test cases to concurrent processes.
Technologies: Oracle, Java
Developer
2005 - 2008
Process Innovation Ag
- Developed for the web with Java and JSP.
- Worked on IMB Lotus Notes and IBM DB2 development.
Technologies: Lotus Notes, JEE, Java
Experience
HN Vanity
An event-sourced application that monitors Hacker News and extracts basic statistics for every story.
The statistics include:
• Title change
• First hit of the front page
• The time it took to hit the front page
• The highest front-page position
• The total time spent on the front page
Implemented with Elixir and PostgreSQL as an event store.
The statistics include:
• Title change
• First hit of the front page
• The time it took to hit the front page
• The highest front-page position
• The total time spent on the front page
Implemented with Elixir and PostgreSQL as an event store.
Release Ping
An overview of the common programming languages and their latest versions (stable and unstable).
How Playing Around with Experimental Technologies Landed Me A 6-month Freelance Gig
An article about my experience building a side project; it has over 9,000 views.
Morfo
https://github.com/leifg/morfoA library that provides a DSL to transform data structures which is very valuable when working on data migrations.
Formulon
https://github.com/leifg/formulonA Salesforce Formula parser that was implemented in pure JavaScript.
Backporting
https://github.com/leifg/backportsThis backports newer functions to older versions of Elixir.
PostgreSQL S3 Backup Docker Container
https://github.com/leifg/postgres-s3-backup-cronA useful docker container that backups PostgreSQL databases to S3 and makes it possible to restore them.
So So Soccer
https://github.com/leifg/so_so_soccerA comparison project between event sourcing and CRUD to solve the same problem: convert a soccer result table into an end-of-the-season standing table.
Time Tracking
https://github.com/leifg/time_trackingI wrote a script to synchronize Toggl time entries with FastBill.
Education
2005 - 2008
Bachelor's Degree in Computer Science and Business Administration
DHBW Karlsruhe - Karlsruhe, Germany
2005 - 2008
Bachelor's Degree in Computer Science
The Open University - London, England
Skills
Libraries/APIs
pgRouting, Salesforce API, Salesforce Bulk API, Salesforce REST API, React
Tools
Git, Tmux, Lotus Notes
Languages
Ruby, Elixir, JavaScript, Elm, Java, JRuby
Frameworks
Ruby on Rails (RoR), Phoenix
Paradigms
REST, CQRS, Event Sourcing
Platforms
Salesforce, Visual Studio Code (VS Code), Oracle, Apache Kafka, Docker, Heroku, JEE
Storage
Redis, PostgreSQL, MySQL, MongoDB, Neo4j
Other
Events
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