Jeffrey A. Dettmann
Verified Expert in Engineering
Software Developer
Jeff has broad experience using multiple technical stacks. Where he excels is data migration, ETL, and resolving difficult problems, 例如调试不熟悉的应用程序和集成设计为独立工作的系统. While Jeff began working in technology in a university setting, he also has experience working in companies—both small and large.
Portfolio
Experience
Availability
Preferred Environment
Linux Mint, Ubuntu, Git, Emacs
The most amazing...
...integration I've orchestrated involved two outside vendors, two internal departments, and three software development teams.
Work Experience
RoR Developer
Spin
- Refactored an application to accept multiple payment processors. The existing system was hard-coded to use Stripe.
- 在可用时设置更新到收费功能,并在故障时无缝回退. 最初的系统向客户收取象征性的费用,并在完成乘车后产生新的费用. Updating the existing charge improved the collection rate.
- 添加了一个Rake任务来更新与团队相关的测试套件的VCR磁带. 现有的应用程序是一个整体,因此该任务不能影响其他团队的流程.
Back-end Developer
NexHealth
- 从在客户机托管的Python应用程序上使用配置文件过渡到从服务器检索配置.
- Ported the notification logic from Python to Ruby on Rails.
- 增加了从客户端系统中删除同步数据的重复检查.
Software Developer
Rosetta Stone
- 将69个语言学习活动模型的内容从两个系统转换为具有偶数模型的单个系统,并构建托管这些新模型的服务器.
- 使用shim服务器协调将调度服务从供应商转移到内部,没有停机时间,也没有更改调度服务客户端软件.
- Built a server in R for evaluating courseware efficacy.
- Developed a performance monitoring system using Splunk.
- 用Python编写多个脚本,用于可视化软件使用统计.
- Built and maintained multiple microservices, including authorization, authentication, and content servers.
- 在Python中创建了一个迁移工具,该工具对多个服务进行经过身份验证的REST调用,以构建新的配置文件, with associated privileges, in a new application.
- 开发与外部供应商系统的多个定制集成.
Software Developer
Browser Media
- 为众多客户定制开源内容管理系统.
- Performed a batch conversion of hundreds of media files to Flash.
- Coordinated the integration of a CMS with clients' software.
- Added an Amazon S3 storage module for the CMS, as the previous system stored media files on a server, which was unsuitable for video.
Senior Systems Analyst
The University of Texas at Austin
- Migrated a legacy JCL-generated code to a new system.
- 构造了一个工具来生成JCL作业队列有向图的SVG.
- Added a secure storage system to an internal storage tool.
- 使用NATURAL和ADABAS开发和维护大型机应用程序.
- 构建实用程序以生成大型机应用程序的测试代码.
Experience
Migration of a Scheduling System
我为该服务构建了一个反向代理,并让所有客户端应用程序都指向它,而不是指向供应商服务. Then, 我开始转换调用,以便代理在从供应商服务读取数据的同时写入两个调度服务. By implementing this process, 我可以同步两个调度服务中的数据,而不需要任何停机时间.
After the full data synchronization, 我重新配置了服务,以便从服务中读取数据,并将结果转换为与供应商服务的API相匹配. At this point, 两个部门的开发团队都能够在他们需要的时候集成新服务,同时保持完整的正常运行时间和数据完整性.
Debugging the Degradation of a Service
Faced with the data, 供应商同意问题出在他们这边,并重新启动了他们的服务器, which temporarily addressed the issue. 我设置了一个脚本来监控服务的平均登录延迟, 因此,在用户开始抱怨并要求供应商重新启动之前,我们就注意到了性能下降.
Data Visualization of Skipped Activities
我开发了一个跳转模式的可视化图,显示了选择下一个活动的方法如何加剧了用户的挫败感,并增加了完全跳过该部分的可能性. 我的工作导致了为用户选择活动的算法的修正.
Reversible Data Migration
For the most part, the migration was seamless, but on occasion, 转换后的数据需要手动验证,并可能进行修改以继续所需的行为. This process was completely reversible, so if the conversion went too far, 业主可以回到使用旧系统,同时确定他们的最佳前进道路.
SVG Representation of a Dependency Graph
这些作业网络的数据模型是节点和边的集合,这些节点和边通过通用命名标准绑定在一起. So one record would say: "A triggers B on success," and another record would say: "B triggers C on success.“系统会通过名字A、B和C知道他们都是同一个工作网络的一部分.
我的任务是获取这些节点和边的集合,并在SVG中呈现有向图,以便用户可以轻松地可视化其作业网络的依赖关系.
Skills
Frameworks
Ruby on Rails (RoR),缩放敏捷框架(SAFe), RStudio Shiny
Languages
SQL, Ruby, Python, Java, NATURAL, R, Bash, XSLT, XPath, XML
Libraries/APIs
Ruby on Rails API, Matplotlib, Pandas, FFmpeg, ImageMagick, PIL, Stripe API
Storage
MySQL, ADABAS, Amazon S3 (AWS S3), CouchDB, MongoDB, JSON, PostgreSQL
Tools
Emacs, Vim Text Editor, RSpec, RuboCop, RabbitMQ, Git, Subversion (SVN), Perforce, Jenkins, Splunk, Adyen Payments, TeamCity, VCR, DataViz
Paradigms
Scrum, Test-driven Development (TDD), ETL Implementation & Design, ETL
Platforms
RStudio, Linux Mint, Ubuntu, Docker
Other
RSync, Pdf2xml, Tesseract, APIs, SVG, Scrum Master
Education
PhD Degree in History
University of Texas, Austin - Austin, TX, USA
Bachelor of Arts Degree in Geography
University of Chicago - Chicago, IL, USA