× {{alert.msg}} Never ask again
Ariadni-Karolina Alexiou

Ariadni-Karolina Alexiou

Python expert for Data Applications & Web Dev

Bern (+01:00)
German, Greek, Spanish, English
I'm a Python and Java/Scala developer, with main focus on Big Data solutions and some full stack web dev experience. I will happily look at your code or system and point out bugs or suggest a better way to do something. Have experience with most popular Python libraries including pandas, matplotlib and numpy. If you want a great code review/refactoring of your Python code, from which you are going to learn and improve as a developer, I am the person to go to. If you have a data transformation that is taking ages, ask me for my help. I have been able to achieve speedups of up to 500x for people here, by using libraries such as pandas in an optimized way and being aware of memory usage patterns. I also am particularly well versed in geospatial data management and the open source project QGIS. I'm a big fan of clean, testable and tested code with a wow factor. I'm also striving for automating everything with the correct tools. I have also worked at Google. I love consulting people via codementor. So far I have walked people through building web apps in Python, solved tough bugs in complex systems and shared my expertise in designing data pipelines. I also have, among other things, helped parallelize code that analyzes DNA sequences, configured git servers and showed people how to get started with unit tests.
Level up your Python

Level up your Python

$100 - Delivery in 1 Day

There are a few things that hold programmers back when learning a language - those are: Not quite knowing how to use external libraries, not knowing how to debug (except by print statements) and being unaware of language idioms and no nos. So, do you want to be able to read and understand Python code better? Do you want to be able to debug efficiently? Do you want to avoid mistakes that interviewers notice and write impressive code instead? I will review your code and point those out, show...

Python expert help Python - 4 years experience
Python is my best language. I have used it to build complex data analysis pipelines and also for data science to employ and evaluate models (to draw insights out of big datasets) Here is an article I have written on the topic: https://www.airpair.com/python/posts/top-mistakes-python-big-data-analytics
Flask expert help Flask - 2 years experience
I have built some websites for internal use in my previous company that allowed us to explore our data
No icon Data Science - 2 years experience
I have done some data exploration to generate insights for customers. Well-versed in the necessary tools to find and present insights. (plotting libraries, etl libraries, scikit-learn)
No icon Databases - 5 years experience
Experience working with relational and non-relational databases to handle complex data. Also was a teaching assistant for a databases course
Java expert help Java - 4 years experience
Have experience with several libraries including Guava, javax.mail and Google Drive java api
Cplusplus expert help C++ - 6 years experience
Development on the open source mapping project QGIS Developed a new high performance trie-like data structure which was published in a top conference in the field. I have occasionally used CGAL (computational geometry library) and boost.
Javascript expert help JavaScript - 6 years experience
I have done data-driven interactive visualizations with javascript (in particular beautiful moving data on the map).
Scala expert help Scala - 1 year experience
Have coded applications dealing with loading and transforming data. Right now I'm developing a system to automate the data flow of the New Incentives charity organization (http://newincentives.org/) which integrates several APIs.
Git expert help Git - 3 years experience
Setting up git servers, resolving branch issues
No icon Gis - 2 years experience
I have collaborated on a python plugin which lets users step through their geospatial data in time (https://github.com/anitagraser/TimeManager)
No icon Ansible - 1 year experience
Used Ansible to provision web servers on CentOS, Debian and Ubuntu machines.
No icon D3 - 1 year experience
I have experience using d3 for interactive visualizations. A lot of people on codementor have asked me to tutor them, so I have put together some tutorials/lessons I can go through to get you started.
articles 4   0
Articles by me!
doge 3   0
wow very terminal doge
pydata 2   1
Data for the exercise presented at PyData Berlin 2014
Subs.py 2   0
Subtitle Syncer
adaptive_range_filters 1   0
C C++ Python Makefile
 Reputation: 1634
  •  Gold Badge: 1
  •  Silver Badge: 11
  •  Bronze Badge: 21
Average Rating
(94 ratings)
Awesome mentor!
Pretty good
Could've been better
Needs improvement

Excellent data analysis help in python.
Brian Maimone Nov 25, 2016

Excellent help on data exploration using python.
Brian Maimone Nov 16, 2016

Carolina knows Python very well, and was able to give me some really useful tips to improve my code efficiency and elegance.
Chris Aug 25, 2016

Karolina is a wonderful mentor. She very patiently listened to my challenge and was quick to comprehend it. She then walked me through an elegant and skillful solution, while sharing some extra pointers about Python and Pandas along the way. I'm so grateful to have worked with her and look forward to future collaborations.
Matt Warfield Jun 02, 2016

Great mentor! Very helpful
Julian May 26, 2016

Karolina is always on point. Very sharp and helpful.
Dan Hassan Apr 10, 2016

Very impressed that Karolina was able to comprehend the project so quickly... and we agreed to a course of action. Very happy.
Dan Hassan Mar 29, 2016

Data Science master!! Great teacher :D
Tyler Waitt Mar 23, 2016

grasped very quickly what the goal was, very happy with everything
Alexander Freise Mar 16, 2016

Caroline was super helpful I will definitely use her again!
ade Mar 10, 2016

Tyler Waitt Mar 10, 2016

Good first session on Python ETL. Looking forward to more.
Roland Ferrao Mar 05, 2016

Experienced and straight to the point. Very helpful
Timothy Lombard Mar 02, 2016

Best mentor/teacher I have ever worked with. Super knowledge around anything I have asked about. She showed me a site for coding practice and we coded some of the problems together and how to use ipdb and debugging techniques.
Mark Feb 20, 2016

Great mentor.
Paul Feb 19, 2016

courtesy and helpful advice. recommended.
Paul Feb 16, 2016

It is kind and helpful. recommended for sessions.
Paul Feb 13, 2016

Great and friendly mentor
Codementor Feb 13, 2016

Good mentor.. recommended to improve their knowledge
Paul Jan 24, 2016

very highly recommended! 5-stars!
Jason Smith Jan 04, 2016

My issue was simple and straightforward but Ariadni is fantastic at explaining her solutions with Python!
Justin Marciszewski Dec 20, 2015

great as always!!
rob Dec 07, 2015

Great career advice!
Andrew Hunter Dec 07, 2015

She really knows her stuff for python, numpy, pandas, scipy, etc. She also knows best practices for writing and debugging code in python. She is far more knowledgable than some other mentors on code mentors that I've happened to deal with before. Highly recommended.
Craig Nov 25, 2015

pretty good
Philip Martin Nov 25, 2015

helpful, knows some great resources
Philip Martin Nov 20, 2015

excellent as always
Taro Woollett-Chiba Nov 11, 2015

Great mentor, helped me with some Python code around data transformations and was very knowledgeable. Highly recommend!
Justin Marciszewski Nov 05, 2015

I'm just starting out, and she was very honest about what she did and didn't know, and got me started in a good direction. I will go back to her once I get a little further along, after exploring the information she gave me.
Taj Carson Nov 03, 2015

Super helpful, thanks so much!
Thomas Chambrier Oct 30, 2015

Very good at getting to heart of the matter and good statistical intuition.
Jeffrey James Oct 30, 2015

Extremely helpful as always. Knowledgable, patient, and thorough. 10/10
Taro Woollett-Chiba Oct 29, 2015

Excellent programmer
ned Oct 24, 2015

I have been learning coding for just over 6 months, and no one ever saw my code besides me. This session was a mind opener on some various concept of Python patterns that Karolina took the time to explain me. The code that had to be reviewed is now solid. I highly recommend her, and will certainly use again.
Philippe Oct 22, 2015

Very helpful and patient. Highly recommended.
ned Oct 21, 2015

Karolina was outstanding! She took a very vague issue, and quickly made it very clear and resolved the issue quite brilliantly. More than that, she took me on as a pair programmer, and was able to guide me while not interfering with my thought process. Especially given that she stayed an entire hour past her office hours to help me get this done. What a brilliant resource she is at CodeMentor.
iamalexcohen Oct 21, 2015

Super helpful and patient as always
Taro Woollett-Chiba Oct 17, 2015

Ariadni was awesome! We talked me through my plan and she let me know a few ways to make things more efficient. Simplicity is the key!
Ish Fuseini Oct 15, 2015

Extremely helpful as always
Taro Woollett-Chiba Oct 14, 2015

Very knowledgable and helpful, highly recommended.
Taro Woollett-Chiba Oct 07, 2015

Just had a great session with this tutor. She did a wonderful job explaining a few things regarding Javascript.
Alex Taghavi Oct 05, 2015

Just had a good session with this tutor. Highly recommend her to anyone who wants to learn Javascript.
Alex Taghavi Oct 03, 2015

Great tutor! I hired Ariadni for Javascript sessions and she's a fantastic teacher. Explains things in detail and a pleasure to work with.
Alex Taghavi Oct 02, 2015

Very good with pandas, data munging and python
Jeffrey James Oct 01, 2015

Great Help
Ralph Sep 29, 2015

Ariadni helped me in every way I hoped, plus more. She performed a code review of a Python program I wrote using Tkinter. This was my first time writing object-oriented code, so she helped me understand the basics of this approach, and she also gave me very good advice for cleaning up my code so that it wasn't so cluttered. This is exactly what I had hoped to learn, and I feel much better equipped after this session. She was very good at explaining concepts, and at times I felt like she was reading my mind. I highly recommend her.
Phineas Gage Sep 28, 2015

This was the best session on codementor that I have had so far. All of my issues were solved and I learned why my code was broken along the way. I will definitely be using her again soon!
Kenny Geiler Sep 27, 2015

Robert Sep 17, 2015

The issue I was facing was a bit more challenging that expected, but Ariadni found the best way around it. She also gave me some advice on my programming along the. I never had anyone comment on my code before - It was a great learning experience!
Colin Lee Sep 08, 2015

Write a public review for this mentor
Robert Sep 07, 2015

Super knowledgeable about pandas and python - got all my questions taken care of quickly.
Jeffrey James Sep 04, 2015

Fast and simple! Had a problem I could not fix and she managed to get it done within a few minutes-literally, just a few minutes!
William Stewart Aug 29, 2015

Great job!
Lourenço Aug 25, 2015

Great work, did it in 24 hours too with some nice features!
rob Aug 24, 2015

Ariadni solved my problem in 10 minutes. I was 48h trying to figure it out and three other developers had told me it was not possible. Highly recommended!
Lourenço Aug 23, 2015

great work as usual!!
rob Aug 20, 2015

Very friendly and helpful. Would definitely use her again!
Steven Haddock Aug 19, 2015

She is incredible!! Fixed a very hard problem in an app that had taken another A+ coder two weeks to build. The same problem had been unsolved by him.
rob Aug 18, 2015

Very knowledgable, helpful, and professional. Thank you!
Robin Chauhan Aug 13, 2015

Es una persona muy profesional, Muy amable y considerada con el tiempo, su español es muy bueno, doy una calificación de 100% y recomiendo su trabajo.
Mauro Soto Del Valle Aug 05, 2015

She was quick to respond and explain things in a helpful way.
Brian Aug 03, 2015

Ariadni was very helpful in getting me up to speed on building a simple api in Flask in an hour. She helped me scope through error or potential problems that I otherwise would have spent more time on. She also offered to clean up my code after we got done!
Haider Khan Aug 02, 2015

was great to have a second brain while coding. managed to solve several tricky issues.
Scott McCallum Aug 02, 2015