# Dennis W.

> ML Software Engineer at Craigslist

Location: San Francisco, California, United States
Profile: https://flows.cv/dennisw

Programmer, UNIX Sysadmin, DBA with 30 years experience in internet and client server application programming and support.  My interests are Artificial Intelligence, Data Mining, Knowledge Discovery and Management and Distributed Systems.

Specialties: Unix Sysadmin, Linux, Solaris, Programming, Perl, Java, C++, DBA, Oracle, Mysql, Postgresql, pl/sql, python, ruby, rails, django, algorithms, nlp

## Work Experience
### ML Software Engineer @ Craigslist
Jan 2012 – Present | San Francisco, California, United States
Machine Learning 
Natural Language Processing NLP
Image Classification
Python programming
Perl and mod_perl programming
Front end HTML and javascript development
Back end development in linux, mysql environment
Map technology including postgis, qgis, geocoding
OpenStreetMaps data

### Principal Engineer @ RPX Corporation
Jan 2011 – Jan 2012
Scale Postgresql database in EC2 cloud.  Perform complex ETL with Pentaho Kettle. Write triggers and stored procedures in pg-pl/sql, pl/ruby.  Create natural language programming NLP routines for entity disambiguation, etc.  Created core database schema model for main business objects; litigations, patents and entities.  Led team of engineers on various projects including loading 7.5 million full text patents into postgres.  Primary postgres DBA.

### Senior Systems Software Engineer @ RPX Corporation
Jan 2010 – Jan 2011
Building out Ruby Rails portal site and CMS with multiple PostgreSQL backend databases, SOLR search, and complicated ETL processes.  Devops with Chef, deploy to Amazon EC2.

### Senior Software Engineer @ GUBA
Jan 2005 – Jan 2010
Developed in Java, Perl, Python, Groovy, SQL.  
DBA for several MySQL databases.  
Sysadmin for 70+ linux servers.
Led teams of engineers on critical projects.
Created video search engine in Java, Lucene, SQL.
DBA for 10+ 24X7 MySQL databases.
Programmed website in Perl with mod_perl and Catalyst.
Tutored junior engineers with SQL, Perl, site architecture.
Created video encoding cloud using VMWare
Programmed video DRM system using Microsoft DRM API.
Created Recommendation Engine with collaborative filtering. 
Championed A/B testing, Analytics and Statistical methods.
Programmed new Video Transcodes including H.264, images
Administered MogileFS, Perlbal Video Streaming
Programmed Groovy Grails web sites.
Performed Ad Hoc queries, Data Mining, Data Analysis work.

### UNIX Systems Administrator @ Monster.com
Jan 2003 – Jan 2005
UNIX Systems Administrator monitors web site, troubleshoot and resolve any issues to ensure 24 by 7 operation.  UNIX Systems Administrator acts as lea son between collocation facilities and Military.com.  UNIX Systems Administrator supports end users from Engineering team on UNIX platform giving advice, creating accounts, installing cron jobs etc UNIX Systems Administrator installs, configures, troubleshoots, and maintains Intel and SPARC hardware, Linux and Solaris OS, and UNIX software such as Apache web server, Postfix mail server, mysql database server, etc.  

UNIX Systems Administrator is also responsible for IP networking, backup Oracle DBA duties, and security of UNIX machines.  UNIX Systems Administrator does scripting and programming to create custom UNIX hardware and software solutions.

### Principal @ DWatson Consulting
Jan 2000 – Jan 2003 | San Francisco Bay Area
Consulted companies in building websites and building online systems

### Senior Software Engineer @ CMP Media
Jan 1997 – Jan 2000
Developed dynamic websites including techweb.com, cmpnet.com and byte.com on Perl, Oracle, Solaris platform.  Served as lead DBA for mission critical Oracle database responsible for 24x7 operation, backup and recovery, tuning and development..  Created solutions for search, categorization, database fail over, automatic feed generation, content management, user authentication, and site statistics.  Eventually lead team of several programmers, sysadmins and DBA responsible for development and maintenance of several hundred sites on a cluster of Solaris machines and EMC SAN.

### Systems Administrator @ Infoscape
Jan 1996 – Jan 1997
Sysadmin for startup company.  Built out corporate network, telephony, and server infrastructure.  Mantained NT domain with several clients.  Managed severl NeXT, Sun, and Linux boxes.

### Programmer / Analyst @ The 3DO Company
Jan 1995 – Jan 1996
Programmed Oracle SQL Forms and Reports, Oracle ERP.  
Created custom corporate budget program in FoxPro (XBase).
Collaborated on initial company intranet and web site.
Created custom web based IT support desk issue tracking system.


## Education
### c++ in oracle DBA, networking, UNIX kernel
UC Berkeley Extension

### BA in English
Syracuse University

### Machine Learning Certificate in Machine Learning
Coursera


## Contact & Social
- LinkedIn: https://linkedin.com/in/dennis-w-204a6a
- Portfolio: http://www.rpxcorp.com

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Source: https://flows.cv/dennisw
JSON Resume: https://flows.cv/dennisw/resume.json
Last updated: 2026-04-10