Constantin Enea

13.12.2018
Constantin Enea (IRIF) will present at POPL 2019 a methodology for specifying software modules whose operations satisfy multiple consistency levels. This work has revealed previously unknown documentation errors and bugs in Java concurrent objects.

Ahmed Bouajjani

9.12.2018
The Alexander von Humboldt Foundation has honored Ahmed Bouajjani (IRIF) with the prestigious Carl Friedrich von Siemens Research Award, in recognition of his research contributions.

Miklos Santha and Troy Lee

3.12.2018
Maybe you are an eager bitcoin miner? Maybe you are a fan of quantum computing too, and you wonder what will change in the mining competition when done by quantum computers? Find some answers in a paper coauthored by Miklos Santha (IRIF) to be presented at ITCS’19.

Mahsa Shirmohammad

19.11.2018
IRIF has the great pleasure to welcome Mahsa Shirmohammadi, researcher scientist (CNRS) from LIS, who is visiting IRIF for six months and who is an expert in the analysis and verification of timed, counter and probabilistic systems.

Jean-Éric Pin

7.10.2018
Jean-Eric Pin, CNRS senior researcher at IRIF, is awarded the Arto Salomaa prize for his outstanding contribution to the field of Automata Theory.

QIP19

20.11.2018
Two papers coauthored by IRIF members will be presented at QIP’19, the main conference for theoretical quantum information research. Topics include efficient quantum algorithms for both algebraic and distributed problems.

SODA19

20.11.2018
One paper coauthored by Laurent Feuilloley while he was PhD student at IRIF will be presented at SODA’19, the main conference in algorithm design. The paper provides lower bounds for the fundamental problem of text indexing with mismatches and differences using the Strong Exponential Time Hypothesis.

ITCS19

21.11.2018
Two papers coauthored by IRIF members will be presented at ITCS’19, a prestigious conference to promote research that carries a strong and innovative conceptual message in TCS. Topics include communication complexity and quantum dueling algorithms.

29.11.2018
Constantin Enea from IRIF organizes with Ruzica Piskac (Yale University), the 20th International Conference on Verification, Model Checking, and Abstract Interpretation (VMCAI 2019). The conference is preceded by a winter school on formal methods.

popl19

17.11.2018
Four papers coauthored by IRIF members will be presented at POPL’19, the main conference on programming languages and programming systems. The papers' topics are game semantics, proof theory, gradual typing, and consistency for concurrent computations.
Games, gradual typing, proofs, consistency

Games are mathematical objects used for modeling situations in which several participants/players interact, and each of them aims at fulfilling a personal goal. Real games such as chess or go are cases in which there are two players which are opponent. Games occur in computer science for modeling the logical duality between conjunction and disjunctions, or for defining particular families of complexity classes. Games appear in verification for describing how a system has to react to the environment (the opponent) in order to perform what it has been designed for.
Gradual typing is a technique that allows the programmer to control which parts of a program check their type correctness (i.e., that apples are added to apples) before execution and which parts check it during their execution instead. It is often used to gradually add the before-execution check to dynamic languages, like JavaScript, which perform the check only at run-time, since it is generally better to find errors before the execution of a program rather than during its execution.
Proof theory is the branch of mathematical logic that studies proofs as mathematical objects. In particular, proof are syntactic constructions built from axioms and inference rules. Relevant to computer science are the studies of computational and complexity aspects of proofs.
Memory consistency models characterize the effect of concurrent invocations to a library implementing a shared state, e.g., a queue or a key-value map. Strong consistency means that the results of concurrently-executed invocations match the results of some serial execution of those same invocations. Since strong consistency carries a significant penalty on performance, modern implementations provide weaker guarantees known as weak consistency models, e.g., eventual or causal consistency.

QIA

12.11.2018
IRIF and PCQC are partners in the EU Flagship project Quantum Internet Alliance (QIA) and in charge of delivering the QIA's blueprint for the future of quantum communications. The EU selected nineteen research projects, and ten of them are based on French teams.

Distinguished Talk

10.11.2018
We are delighted to host as part of our IRIF Distinguished Talks Series Maurice Helihy (Brown University) on Nov. 16, 10:30 for a talk entitled “Atomic Cross-Chain Swaps”.

GDRI

10.11.2018
The last plenary meeting of GDRI Logique Linéaire takes place at IRIF, December 3-5. The program consists of talks given by members of the GDRI.

10.11.2018
The first meeting of the French-Chinese research project Verification Interaction Proof will take place in Paris at IRIF on November 19-24. Registration is free but mandatory.

Graph Theory in Paris

9.11.2018
The first session of a series of seminars Graph Theory in Paris will be hosted by IRIF. There will be two seminars by Monique Laurent and Lex Schrijver on November 23, at 2pm, in Amphi Turing of Sophie Germain building.

logo-cirm.jpg

5.11.2018
Amélie Gheerbrand and Cristina Sirangelo from IRIF co-organize with L. Libkin, L. Segoufin, and P. Senellart, the 2019 Spring School on Theoretical Computer Science (EPIT) on Databases, Logic and Automata, to happen the 7-12 April 2019 in Marseille. Preregistration before 13 January 2019.

5.11.2018
The Journées PPS 2018 will take place on Thursday 8 and Friday 9 November, room 3052, building Sophie Germain.

Adrien Guatto

12.10.2018
IRIF has the great pleasure to welcome a new assistant professor (Paris Diderot): Adrien Guatto, an expert in synchronous languages, typed functional programming, and categorical semantics.

Claire Mathieu

12.10.2018
IRIF has the great pleasure to welcome a new research scientist (CNRS): Claire Mathieu, an expert in algorithms, particularly the design of approximation schemes for NP-hard combinatorial.

Pierluigi Crescenzi

12.10.2018
IRIF has the great pleasure to welcome a new professor (Paris Diderot): Pierluigi Crescenzi, an expert in graph algorithms, particularly in the analysis of real-world complex networks.

Daniela Petrisan

10.10.2018
IRIF has the great pleasure to welcome a new assistant professor (Paris Diderot): Daniela Petrisan, an expert in categories, co-algebra and automata.

ICFP: International Conference On Functional Programming

9.10.2018
The paper “Equivalences for Free : Univalent Parametricity for Effective Transport” of Matthieu Sozeau (IRIF), with his coauthors Nicolas Tabareau and Eric Tanter, has been selected as a distinguished paper of the ICFP conference.

Maths en ville

8.10.2018
Jean Krivine (researcher at IRIF) will lead a public debate about Artificial Intelligence at the “Festival Maths en Ville” of Saint-Denis. It will take place on the 11/10/2018 at the theater “L'écran”, starting at 19.30.

CRECOGI+ELICA+GDRILL Plenary Meeting

8.10.2018
On October 8-11 IRIF organizes a joint meeting of 3 projects which are closely related: GDRI-LL, CRECOGI, and ELICA. Everybody is welcome to attend.

7.10.2018
IRIF is having its back-to-work-day on October 15th. In the morning, there will be a PhD student session, and in the afternoon a series of talks given by new faculty and CNRS members.

IRIF

5.10.2018
IRIF is seeking excellent candidates for about 10 postdoctoral positions in all areas of the Foundations of Computer Science.

Software Heritage

4.10.2018
In an article of October of Communications of the ACM, Jean-François Abramatic, Roberto Di Cosmo (IRIF) and Stefano Zacchiroli (IRIF) explain the mission of the Software Heritage project.

WENDY: Workshop on emergent algorithms

15.9.2018
IRIF co-organizes the Workshop on Emergent Algorithms and Network Dynamics (Wendy) that will take place at Institut Henri-Poincaré in Paris on October 10-11, 2018. Registration is free but mandatory.

COmplexité et Algorithmes

14.9.2018
The October 2, IRIF organizes the next Annual workshop of the French Working Group on Complexity and Algorithms (CoA). This year, the workshop will consist of a series of introductory and survey talks about various hot topics in algorithms, including Blockchains, Machine Learning, Sum-of-Square, etc.

QUANTERA

7.9.2018
The EU QuantAlgo project workshop will be held in Paris at IRIF September 25-28, 2018. This is a joint workshop with the IRIF-IQC Cooperation project between CNRS and U. Waterloo. QuantAlgo project aims to combine research on the fundamentals of quantum algorithms with the development of new applications.

The DUALL project of the ERC

4.9.2018
IRIF organizes the workshop Quantifiers and duality that will take place at Amphi Turing (building Sophie Germain, University Paris Diderot) on the 2018/09/11. Registration is free but mandatory.

FILOFOCS: Frech-Israeli-workshop on foundations of Computer Science

9.8.2018
IRIF organizes the 7th FILOFOCS (French-Israeli Laboratory on Foundations of Computer Science) workshop which will be held at the institut Henri Poincaré (IHP), on 3-5 October, 2018. A preliminary list of speakers in now available and registration (mandatory, but free) is now open.

perso-michel-habib.jpg

1.8.2018
At the occasion of the retirement of Michel Habib and in celebration of his achievements, IRIF organizes a two-day conference “40 années d'algorithmique de graphes”, 11-12 Oct, Amphi Turing (Sophie Germain, Univ. Paris Diderot). Free mandatory registration.

FOCS

29.7.2018
IRIF organizes the 59th IEEE Symposium on Foundations of Computer Science (FOCS 2018) on October 7-9, 2018. FOCS is a leading annual conference in Theoretical Computer Science, and has served in the last 60 years as a venue for announcing the major scientific advances in the field. The list of accepted papers is now available, and the registration is now open (deadline for early rate: September 9, 2018).

FLOC18

10.7.2018
Mihaela Sighireanu (IRIF) is organizing the second edition of SL-COMP, a competition of solvers for separation logic. The final results will be presented at ADSL 2018, a workshop of FLOC2018, which will take place in Oxford on the 13.07.18.
separation logic

Separation logic is a language for describing properties and reasoning about programs that use mutable data structures (i.e. memory cells and pointers). Separation logic has a special support for local reasoning, which is the ability to use and compose properties that involve a subset of the data configuration only: it separates the relevant portion of the data structure from the irrelevant one. Local reasoning gives more compact proofs and specifications for imperative programs than with prior formalisms. Furthermore, it helps with the scalability of proofs done in automatic and semi-automatic verification and program analysis tools.
Avocs'18

6.7.2018
Mihaela Sighireanu (IRIF) is co-chair of the 18th International Workshop on Automated Verification of Critical Systems (AVOCS) which will take place in Oxford from 18.07.18 to 19.07.18 as part of FLOC2018.

LICS

29.6.2018
Raphaëlle Crubillé (PhD student IRIF) will present at LICS 2018 an analytic account of the discrete probabilities fragment of a denotational model for higher-order programming with general probabilities, hopefully a first step towards proving that this model is fully abstract.
fully abstract

The quest for a fully abstract model for the contextual equivalence of PCF, a paradigmatic functional language, has been influential in the area of programming languages semantics. A model is fully abstract if it is both sound and complete. A denotational model is complete for a given notion of equivalence between programs if equivalent programs have the same denotation, some mathematical object they are mapped to; it is sound if programs having the same denotation are equivalent.
CIJM

27.6.2018
Berenice Delcroix-Oger (IRIF) participated to the annual festival Salon Culture & Jeux Mathématiques 2018. On the following video (1:50), she presents a funny game where mathematics help you perform magic tricks!

Amina Doumane

15.6.2018
Amina Doumane (former PhD student at IRIF, now at LIP) was awarded the Ackermann prize of EACSL for her PhD thesis entitled On the infinitary proof theory of logics with fixed points.

IRIF Distinguished Talks

6.6.2018
We are delighted to host as part of our IRIF Distinguished Talks Series Christos Papadimitriou (Columbia University) on July 13, 10:30 for a talk entitled “A computer scientist thinks about the Brain”.

TYPES

6.6.2018
Delia Kesner (IRIF) and Matthieu Sozeau (IRIF) will both give invited talks entitled “Multi Types for Higher-Order languages” and “The Predicative, Polymorphic Calculus of Cumulative Inductive Constructions and its implementation” at TYPES 2018, held in Braga (Portugal), June 18-21.

Softare heritage

6.6.2018
Today Roberto Di Cosmo (professor at IRIF) with a ceremony at UNESCO opened to the public the archives of Softwareheritage.org, a worldwide initiative to create a universal library of computer programme source codes since the dawn of the digital age.

Collège de France

1.6.2018
Claire Mathieu (IRIF associate member) organizes a 1-day colloquium on Approximation algorithms and networks at Collège de France on June 7. This is part of the Chair in Informatics and Computational Sciences at College de France in association with INRIA.
approximation algorithm

The approximation algorithms are algorithms that produce a solution that approximates the best possible solution of an optimization problem. While finding the optimal solution of practical problems is often infeasible, an approximation algorithm usually produces its solution in an efficient way and provides formal guarantees about the quality of the approximation. An example of such a problem is the so-called “traveling salesman problem” which consists in finding among all possible itineraries the shortest route that allows a salesman to visit a given set of cities and come back home.
Logic in Computer Science

31.5.2018
Paul-André Melliès (IRIF) will present at LICS 2018 his work on ribbon tensorial logic, a primary logic designed to reveal the secret topology of reasoning. This is the first time that logical proofs are faithfully translated into topological tangles using functorial knot theory.
knot theory

Knot theory studies mathematical knots. These are like the usual shoelaces and rope knots but with the difference that the ends of the string are joined together so that it cannot be undone. Of particular interest is the study of when two knots are equivalent, that is when one can be transformed into the other without cutting the string or passing the string through itself. The theory has applications in physics, biology, chemistry, and computer science. For instance, the security of some quantum money relies on the assumption that given two different looking but equivalent knots, it is difficult to explicitly find a transformation that takes one to the other.
Tous femmes du numérique !

30.5.2018
« Tous femmes de numérique ! » Après leur rencontre avec 4 informaticiennes de l’IRIF, 14 lycéennes du Lycée Jules Ferry ont expliqué à leurs camarades l’exposition permanente du Palais de la découverte sur l’informatique et les sciences du numérique le 29/05.

Logic in Computer Science

25.5.2018
Marie Kerjean (PhD student IRIF) will present at LICS 2018 a logical account for linear partial differential equations. With this work, she unveils a bridge between mathematical physics and proof theory, paving the way for exciting and mutually beneficial transfers of techniques.
sequent

A sequent represents a theorem by a sequence of hypotheses and the sequence of possible theses they imply. This formalism underlines a symmetry hypotheses/theses ruled by negation and is used in sequent calculus to formalise proofs and to study their properties.
Logic in Computer Science

21.5.2018
Pierre Vial (IRIF) will present at LiCS 2018 an excerpt of his PhD work at IRIF proving that every lambda-term has an infinite linear representation in the infinitary relational model. This work pioneers a technique that allows giving a semantic even to unproductive programs.
unproductive

A part of a program is unproductive if it performs an infinite number of computing steps without any interaction with the rest of the program or external devices. Unproductive code is basically useless, and may even be unsafe, and detecting parts of code that are unproductive is important to improve software quality.
Ants

11.5.2018
Amos Korman (IRIF) Amos Korman is co-chairing, and organizing the 6th Workshop on Biological Distributed Algorithms, to be held in London in July, the 23rd.
biological algorithm

Biological algorithm is a term used to describe the biological processes from an algorithmic, or computer scientific, perspective. It concerns questions such as what are the algorithmic challenges faced by the biological organism, and what are the algorithmic principals used in order to overcome these challenges. For example, when a group of ants finds a large piece of food and needs to decide its navigation rout back to the nest, what are the benefits and pitfalls of noise in their communication?
Institue de France

4.5.2018
Miklos Santha (IRIF) participates to the conference-debate Calcul, communication, simulation et métrologie quantiques : des principes aux réalisations concrètes organized by Académie des sciences at the Institut de France on May 15.

Institut Universitaire de France

27.4.2018
IRIF is proud to announce that Delia Kesner, professor of University Paris Diderot and researcher at IRIF, was appointed senior member of IUF.

Logic in Computer Science

23.4.2018
Six papers coauthored by IRIF members will be presented at the prestigious conference LICS'18 in Oxford this summer. Topics range from λ-calculus, to Separation Logic…

Research at Google

6.4.2018
Victor Lanvin (PhD student of Giuseppe Castagna, IRIF) is awarded the Google PhD fellowship! Through the FSMP, Google will give a significant support to Victor's research work on gradual typing.
gradual typing

Gradual typing is a technique that allows the programmer to control which parts of a program check their type correctness (i.e., that apples are added to apples) before execution and which parts check it during their execution instead. It is often used to gradually add the before-execution check to dynamic languages, like JavaScript, which perform the check only at run-time, since it is generally better to find errors before the execution of a program rather than during its execution.
Numeration 2018

3.4.2018
The conference Numeration 2018 will be held on May 22-25 at the University Paris Diderot, and is organized by Valérie Berthé, Christiane Frougny and Wolfgang Steiner from IRIF.

The Kappa platform for rule-based modeling

21.3.2018
“The Kappa platform for rule-based modeling”, a collaboration between Jean Krivine (IRIF) and researchers from Harvard University, ENS and Santa Cruz University will be presented at ISMB2018.

Agence Nationale pour le Recherche

21.3.2018
The next meeting of the ANR project DESCARTES, aiming at defining a modular approach for distributed computing, will take place at IRIF on March 28, 2018. Scientific talks are public.

ANR Delta

21.3.2018
The next meeting of the ANR project DELTA, conducting research about the new challenges in Logic, Automata and Transducers, will take place at University Paris Diderot from 2018/03/26 to 2018/03/28. Scientific talks are public.
automaton

An automaton is a construct made of states designed to determine if a sequence of inputs should be accepted or rejected. It starts from initial state and when it receives a new input it moves to another state according to the way it was programmed. If at the end of all inputs the automaton is in a state designated as final, then the sequence of inputs is accepted, otherwise it is rejected.
IRIF Distinguished Talk

8.3.2018
In the scope of the IRIF Distinguished Talks Series Monika Henzinger (University of Vienna) will give on April 13 a talk on “The state of the art in dynamic graph algorithms”.
algorithm

Algorithm: an algorithm is the formal description of a procedure that is used to solve a class of problems. The description consists in a sequence (of finite length) of operations that are interpreted unambiguously by who/what is executing the algorithm. Every algorithm can be directly executed or simulated by any Turing-complete system.
STOC

2.3.2018
Adrian Kosowski (IRIF), together with Bartek Dudek (University of Wroclaw), will present at STOC 2018 a new protocol for spreading information in a population. This is the first time that methods of oscillatory dynamics are used to solve a basic task of information dissemination.
information dissemination

Information dissemination is the process by which a piece of information is propagated in a distributed system through direct communications from node to node. Rumor spreading between humans or broadcasting in a network are two typical examples. Information propagation is a basic building block of many distributed algorithms and its analysis is often critical in understanding their complexity.

27.2.2018
Constantin Enea (IRIF) is an organizer of the 2018 edition of the EPIT research school, on the subject of software verification, to he held in Aussois on May 7-11 2018.

Fondation Sciences Mathématiques de Paris

27.2.2018
FSMP offers 20 PhD student positions in Maths and TCS under H2020 COFUND project MathInParis. As a member of the FSMP network, IRIF is an eligible hosting lab. Call for application is open until April, 1st 2018. Applicants must be international students, but master students already in France for less than a year are eligible.

MOVEP

7.2.2018
Peter Habermehl (IRIF) and Benedikt Bollig (LSV, ENS Paris-Saclay) organize the research school MOVEP (Modelling and Verification of Parallel Processes), on July 16-20 in Cachan.

Université Paris 7 - Denis Diderot

5.2.2018
Université Paris Diderot has opened three permanent positions in Computer Science (1 professor on Graph and applications, 1 assistant professor on Software Science, 1 assistant professor on Data Science). Recruited researchers will join IRIF.

Palais de la Découverte

4.2.2018
Laurent Viennot (IRIF, Inria) is Scientific Curator of the exhibition Informatique et sciences du numérique, at Palais de la découverte, starting March 13, 2018.

Amina Doumane

2.2.2018
Amina Doumane, now at LIP, was awarded the “La Recherche” prize in the Computer Science category for her paper entitled Constructive Completeness for the linear-time mu-calculus, a work accomplished during her PhD at IRIF and that appeared in the proceedings of LICS’17.

Nature

1.2.2018
The first on-the-fly quantum money transaction was implemented by researchers in Paris, including Iordanis Kerenidis. ​Quantum ​money is provably unforgeable​ due to the no-cloning property of quantum information.​
quantum information

Quantum Information is the information stored in a quantum system. A quantum system is composed of one or many qubits: the fundamental unit of quantum information. A qubit is a 2-dimensional vector. The basis encodes two classical values of a bit. Quantum information, i.e. Von Neuman entropy, is the analogous of Shannon entropy for classical information, and it is often used to measure physical properties of a quantum system, like the entanglement.
Lia INFINIS

27.1.2018
The international French and Argentina CNRS laboratory called INFINIS lead by Delia Kesner (IRIF) and Sergio Yovine (CONICET) is presented in the CNRS Rio newsletter.

Maurice Nivat

18.1.2018
IRIF organizes on February, 6th a Scientific Day in memory of Maurice Nivat, professor at Paris Diderot University and a pionneer of theoretical computer science. Please register.

Agence Nationale pour le Recherche

11.1.2018
January the 10th 2018, this is the kick-off meeting of the ANR project FREDDA (FoRmal mEthods for the Design of Distributed Algorithms).

Innovations in Theoretical Computer Science

5.1.2018
Lucas Boczkowski and Amos Korman from IRIF, with their co-authors, will present at ITCS 2018 a non-conditional lower bound on information dissemination in stochastic populations. The paper is the first ever to combine an algorithmic lower bound with a biology experiment in collective behavior.

Convention Industrielle de Formation par la Recherche

19.12.2017
IRIF and ATOS have started the first Industrial PhD Thesis (CIFRE) on quantum algorithms in France. The PhD candidate Alessandro Luongo is co-advised by Iordanis Kerenidis and Frédéric Magniez.

Société Informatique de France

29.11.2017
Wenjie Fang was awarded the Honorable Mention of the Gilles Kahn prize for his PhD thesis entitled « Aspects énumératifs et bijectifs des cartes combinatoires : généralisation, unification et application » and supervised by Guillaume Chapuy and Mireille Bousquet-Mélou.

Société Informatique de France

29.11.2017
Amina Doumane was awarded the Gilles Kahn prize for her PhD thesis entitled « On the infinitary proof theory of logics with fixed points » supervised by Alexis Saurin, David Baelde and Pierre-Louis Curien.

Maurice Nivat

27.11.2017
Scientific Day in memory of Maurice Nivat, professor at Paris Diderot University and a pionneer of theoretical computer science in France and in the world, who passed away on September the 21st, 2017.

IRIF

25.11.2017
Back-to-work day of the “Automata, Structures, and Verification” pole, which gathers the research groups Automata and applications and Modelling and verification on November 25, 2017.

IRIF

22.11.2017
6th French-Israeli Workshop on Foundations of Computer Science on November 22-23, 2017 at Tel-Aviv University, Israel.

IRIF

15.11.2017
2-day workshop on December 7-8: Closing workshop of ANR project on Restricted Data Access Models and 1st IRIF-IQC Workshop on Quantum Information Processing (CNRS bilateral collaboration).

IRIF

6.11.2017
IRIF newcomers Day on November 6, 2017 at Amphi Turing

IRIF

10.10.2017
Back-to-work day of the “Proofs, programs and systems” pole on October 12-13, 2017 at room 3052.

ACM-SIAM event

6.10.2017
Guillaume Lagarde and Sylvain Perifel have solved a 20-year old conjecture related to Lempel-Ziv. This will be presented at the 29th ACM-SIAM Symposium on Discrete Algorithm (SODA 2018).

SODA

1.10.2017
Two papers coauthored by IRIF members will be presented at SODA’18, the main conference in algorithm design. Topics include the resolution of a 20-year old conjecture related to Lempel-Ziv, and a new approximation algorithm for recognizing Dyck languages.

Bérénice Oger

1.9.2017
IRIF has the great pleasure to welcome a new assistant professor: Bérénice Delcroix-Oger, an expert in combinatorics and computational algebra.

ANR project MealyM

10.7.2017
Closing workshop of ANR project MealyM on July 10-13, 2017 at Amphi Turing.

Victor Lanvin

15.6.2017
Victor Lanvin is awarded the first prize for the ACM Student Research Competition Grand Finals, undergraduate category. The prize will be presented on June the 24th at the Turing Award Cerimony in San Francisco.

European Research Council

1.3.2017
The 5-year ERC project CombiTop of Guillaume Chapuy has started on March 1st, 2017. The purpose of this project is to use the ubiquitous nature of certain combinatorial topological objects called maps in order to unveil deep connections between several areas of mathematics.

Le Monde

30.1.2017
Amos Korman has been interviewed by Le Monde for his recent results on ants with several co-autors at IRIF.

Principle of Programming Languages 2017, Paris

2.1.2017
IRIF organizes the 44th ACM Symposium on Principles of Programming Languages (POPL 2017), Jussieu, Paris, January 15-21, 2017.