François Lewis successfully defended his Ph.D. thesis.
I like crazily fast code.
Daniel Lemire is a computer science professor at the Université du Québec (TELUQ). He has also been a research officer at the National Research Council of Canada and an entrepreneur. He has written over 85 peer-reviewed publications, including more than 60 journal articles. He wrote several books. He has held competitive research grants for the last 20 years. He is editor of the Software: Practice and Experience journal, established in 1971. He serves on the program committees of leading computer science conferences (e.g., ACM CIKM, WWW, ACM WSDM, ACM SIGIR, ACM RecSys). His software is used by major corporations like Microsoft, Google and Meta. In 2020 and 2021, Daniel Lemire was co-chair of the NSERC computer science committee. He received the University of Quebec’s 2020 Award of Excellence for Achievement in Research (all fields) for his work on the acceleration of JSON parsing. Daniel Lemire is among the 2% most cited scientists in the world (Stanford University/Elsevier rankings, 2024).
He programs in C, C++, Java, JavaScript, Python, Swift and Go. He works primarily in an open-source setting. You can find his software in Git, in Node JS, and so forth. In 2012, he was rewarded by the Google Open Source Peer Bonus Program. In February 2019, he was ranked in second position among the most popular developers on GitHub and most popular in C++ (ahead of Microsoft, Google and Facebook). He is among the 0.0006% most followed programmers in the world on GitHub; GitHub has over 100 million developers.
He is a long-time social media user: his blog has thousands of readers and was featured on Slashdot, Reddit and Hacker News. He was one of the first Twitter users: @lemire.
He is a founding member of the DOT-Lab Research Center where students and professors do research on data science. He is an adjunct professor at UQAM within the computer science department where he is a member of the LATECE laboratory. He is also an adjunct professor at the University of New Brunswick within the computer science department.
We offer scholarships for graduate studies in software performance for data engineering (in French).
PhD in Engineering Mathematics, 1998
École Polytechnique and Université de Montréal
MSc in Mathematics, 1995
University of Toronto
BSc in Mathematics (High Distinction), 1994
University of Toronto
I take the production of software seriously. You can find most of my software on GitHub.
Some noteworthy contributions:
Some of my blog posts lead to improvements in widely used software.
Some of our research articles have also have notable impacts.
Dictionary class and to accelate virtual function calls.You can find my work on arXiv, on Google Scholar, on DBLP, on the ACM Portal, on R Libre and elsewhere.
I regularly give industrial talks; they are often well received. My QCon San Francisco 2019 talk was outlined as a “best voted” talk with 98% of the audience giving it thumbs up; this is much higher than the average.
Sat, Nov 11, 2023, NodeConf EU 2023
Fri, Jun 16, 2023, Invited talk at the Filter Workshop, Workshop held in conjunction with SPAA 2023 (June 16, 2023 - Orlando, USA)
Sat, Feb 25, 2023, Invited talk at the SIGPLAN BID 2023, Benchmarking in the Data Center: Expanding to the Cloud, Workshop held in conjunction with PPoPP 2023: Principles and Practice of Parallel Programming 2023 (February 25, 2023 - Montreal, Canada)
Fri, Oct 1, 2021, Invited talk at SPIRE 2021, 28th International Symposium on String Processing and Information Retrieval (October 4-6th, 2021 - Lille, France)
Wed, May 12, 2021, MIT Fast Code Seminar
Wed, Oct 7, 2020, Go Systems
Tue, Jun 16, 2020, Performance Summit III (Facebook)
Mon, Oct 7, 2019, QCon San Francisco 2019
Wed, Feb 7, 2018, ODSC East 2018
Tue, Feb 7, 2017, Spark Summit East 2017
Parsing gigabytes of JSON per second
Unicode routines: billions of characters per second.
Routines rapides de lectures de nombres à virgule
Fast compressed bitmaps, widely used. (picture: Edge Earth)
We are lucky to have a fully equipped laboratory with a dedicated technician. We have a server farm that has been used worldwide for experiments in software performance (e.g., by researchers such as Agner Fog). We also have several powerful workstations and beautiful white boards!
I teach primarily in French and online since 2004.
Undergraduate courses:
Graduate courses:
I’m recruiting students and postdoctoral fellows for my lab. If you love writing crazily fast software and want to come to Montreal, drop me a line. Link to an impressive GitHub profile is an asset. Speaking French is an asset if you want to pursue an academic program with me. Some of my best students are women. We offer scholarships for graduate studies in software performance for data engineering (in French).
If you are a Canadian undergraduate student with at least a B average, you might be interested in coming to work with me under an NSERC Undergraduate Student Research Awards. The awards help pay for a full-time research project in our Montreal labs. The application deadlines are:
It is an ongoing competition: I can receive applications for every term. Please allow at least a week to put together an application with my help. Email me if you are interested.
If you are interested in pursuing a master in information technology full-time under my supervision in Montreal and you know some French, I take applications for NSERC Graduate Scholarships. You need to have a strong academic profile to apply. You should be a Canadian citizen or permanent resident of Canada. The deadline is December first of each year. You must plan ahead. I take applications every year. Please get in touch by email if you are interested.
If you are interested in pursuing a Ph.D. in cognitive computing full-time under my supervision in Montreal and you know some French, I take applications for NSERC graduate scholarships. You need to have a strong academic profile to apply. You should be a Canadian citizen or permanent resident of Canada. The deadline is November 1st of each year. You must plan ahead. I take applications every year. Please get in touch by email if you are interested.
I supervise graduate students at the University of Quebec (TÉLUQ and UQAM). I also co-supervise students the University of New Brunswick, at the École Polytechnique and at Concordia University.
Some recent graduates:
Some alumni:
Current Ph.D. students:
Current M.Sc. students:
Recent research assistants (undergraduate):
Recent research guests:
Mentoring
François Lewis successfully defended his Ph.D. thesis.
Daniel Lemire was inducted into the Circle of Excellence of the University of Quebec
Pierre Marie Ntang successfully defended his Ph.D. thesis.
Nigel Medforth successfully defended his Ph.D. thesis.
Prior to the 2020 events, I was the organizer of an ongoing series of workshops open to the public: the technolab workshops and the tribalab workshops.
I have served in the program committee of several international conferences such as
In 2019, I was the chair of EDA 2019 (Business Intelligence & Big Data) held in October at Montpellier, France.
In 2018, I was recognized by the journal Software: Practice and Experience as a distinguished referee for my “insightful, careful, constructive and timely reviews”.
In June 2018, I participated to the Dagstuhl Seminar 18251: Database Architectures for Modern Hardware.
I am editor of the Software: Practice and Experience journal (Wiley) since 2021. I was associate editor of the computer science section of the Heliyon journal (Elsevier) from 2015 to 2020.
I recently served on the following program committees:
I was an external referee for the following Ph.D. students:
I was an external referee for the following M.Sc. students: - Benjamin Lapointe-Pinel from UQAR, Canada (2024) - supervised by Steven Pigeon.
In 2020, I was one of two external reviewers for the M.Sc. in computer science program assessment at UQAC.
I served as a committee member for several funding bodies:
In 2022, I was a member of the university sub-committee on engineering and information technologies, within the committee on the implementation of the measures of the Quebec government’s Operation Manpower.
Articles and interviews
Click on the picture for a high resolution version.
