Roberto Di Cosmo

Bio: Roberto Di Cosmo is an academic researcher from French Institute for Research in Computer Science and Automation. The author has contributed to research in topics: Software & Component-based software engineering. The author has an hindex of 25, co-authored 102 publications receiving 1870 citations. Previous affiliations of Roberto Di Cosmo include École Normale Supérieure & University of Paris.

Managing the Complexity of Large Free and Open Source Package-Based Software Distributions

Abstract: The widespread adoption of Free and Open Source Software (FOSS) in many strategic contexts of the information technology society has drawn the attention on the issues regarding how to handle the complexity of assembling and managing a huge number of (packaged) components in a consistent and effective way. FOSS distributions (and in particular GNU/Linux-based ones) have always provided tools for managing the tasks of installing, removing and upgrading the (packaged) components they were made of. While these tools provide a (not always effective) way to handle these tasks on the client side, there is still a lack of tools that could help the distribution editors to maintain, on the server side, large and high-quality distributions. In this paper we present our research whose main goal is to fill this gap: we show our approach, the tools we have developed and their application with experimental results. Our contribution provides an effective and automatic way to support distribution editors in handling those issues that were, until now, mostly addressed using ad-hoc tools and manual techniques.

Software Heritage: Why and How to Preserve Software Source Code.

Abstract: Software is now a key component present in all aspects of our society. Its preservation has attracted growing attention over the past years within the digital preservation community. We claim that source code—the only representation of software that contains human readable knowledge—is a precious digital object that needs special handling: it must be a first class citizen in the preservation landscape and we need to take action immediately, given the increasingly more frequent incidents that result in permanent losses of source code collections. In this paper we present Software Heritage, an ambitious initiative to collect, preserve, and share the entire corpus of publicly accessible software source code. We discuss the archival goals of the project, its use cases and role as a participant in the broader digital preservation ecosystem, and detail its key design decisions. We also report on the project road map and the current status of the Software Heritage archive that, as of early 2017, has collected more than 3 billion unique source code files and 700 million commits coming from more than 50 million software development projects.

Provable isomorphisms of types

Abstract: A constructive characterization is given of the isomorphisms which must hold in all models of the typed lambda calculus with surjective pairing. By the close relation between closed Cartesian categories and models of these calculi, we also produce a characterization of those isomorphisms which hold in all CCC’s. By the correspondence between these calculi and proofs in intuitionistic positive propositional logic, we thus provide a characterization of equivalent formulae of this logic, where the definition of equivalence of terms depends on having “invertible” proofs between the two terms. Rittri (1989), on types as search keys in program libraries, provides an interesting example of use of these characterizations.

Extensional normalisation and type-directed partial evaluation for typed lambda calculus with sums

Abstract: We present a notion of η-long β-normal term for the typed lambda calculus with sums and prove, using Grothendieck logical relations, that every term is equivalent to one in normal form. Based on this development we give the first type-directed partial evaluator that constructs %able to construct normal forms of terms in this calculus.

Package upgrades in FOSS distributions: details and challenges

Abstract: The upgrade problems faced by Free and Open Source Software distributions have characteristics not easily found elsewhere. We describe the structure of packages and their role in the upgrade process. We show that state of the art package managers have shortcomings inhibiting their ability to cope with frequent upgrade failures. We survey current counter-measures to such failures, argue that they are not satisfactory, and sketch alternative solutions.

QoS-Aware Deployment of IoT Applications Through the Fog

Abstract: Fog computing aims at extending the Cloud by bringing computational power, storage, and communication capabilities to the edge of the network, in support of the IoT. Segmentation, distribution, and adaptive deployment of functionalities over the continuum from Things to Cloud are challenging tasks, due to the intrinsic heterogeneity, hierarchical structure, and very large scale infrastructure they will have to exploit. In this paper, we propose a simple, yet general, model to support the QoS-aware deployment of multicomponent IoT applications to Fog infrastructures. The model describes operational systemic qualities of the available infrastructure (latency and bandwidth), interactions among software components and Things, and business policies. Algorithms to determine eligible deployments for an application to a Fog infrastructure are presented. A Java tool, FogTorch , based on the proposed model has been prototyped.

Extensional rewriting with sums

Abstract: Inspired by recent work on normalisation by evaluation for sums, we propose a normalising and confluent extensional rewriting theory for the simply-typed λ-calculus extended with sum types. As a corollary of confluence we obtain decidability for the extensional equational theory of simply-typed λ-calculus extended with sum types. Unlike previous decidability results, which rely on advanced rewriting techniques or advanced category theory, we only use standard techniques.