We do research in the design and implementation of programming languages (PL), mathematical models of computation, and computer-assisted formal reasoning.
Our results address software reliability issues that arise in everyday job of software developers. we do so by investigating theoretical foundations and building tools for ensuring that certain kinds of costly software errors and vulnerabilities never occur in the real-world code, which many people rely upon in their everyday lives.
Our current investigations follow the themes outlined below.
For more details on our research, check out our blog posts, projects, and recent papers.
It is hard to overstate the significance and ubiquity of distributed services in many aspects of modern life, such as health care, online commerce, transportation, entertainment and cloud-based applications. Given the importance of distributed software and its complexity, it is vital in industry to have a rigorous verification methodology for establishing its correctness properties, ensuring that, once a distributed system is up and running, it will never go wrong and will eventually complete its goals.
Our recent work has established logical foundations for compositional verification of complex distributed protocols using a proof assistant. We have also produced the first mechanically verified proof of safety of Nakamoto consensus. Our ongoing work builds libraries and techniques for mechanised reasoning about probabilistic properties of distributed protocols and data structures employed by them. In particular, we have produced the first mechanised proof of the false-positive ratio for Bloom filters (see this blog post for more details).
In this line of research we apply core PL techniques, such as semantics, type systems, and abstract interpretation, for building safe and secure decentralised applications.
For instance, in our recent work, inspired by the verification ideas from Theme 1, we have developed a library for compositional construction of distributed protocols, allowing their modular testing and model-checking. By reflecting on the analogy between design principles of secure smart contracts (a particularly prominent class of decentralised applications) and concurrent software (also see the related ACSAC'18 and ISSTA'19 papers), in collaboration with industry partners we have developed Scilla, a functional smart contract language with strong safety guarantees. We have also developed a set of efficient compilation techniques for Scilla as well as a Coq-powered verification methodology for it.
Our ongoing research explores opportunities for (a) developing low-overhead abstractions for automated reasoning about distributed applications and (b) enhancing parallelism offered by modern distributed protocols via programming language techniques.
Program synthesis is an emerging research and technology paradigm for automatically deriving programs from user-provided declarative specifications, thereby significantly reducing the implementation effort required for producing correct-by-construction and efficient code.
Our recent work explored applications of state-of-the-art techniques for analysis, verification, and deductive proofs for fast and expressive program synthesis (check out the papers on SuSLik and ROBoSuSLik) and for program repair. Our long-term agenda involves synthesis of correct concurrent and distributed programs by adopting our work on static analysis and logical foundations for reasoning about concurrent and distributed systems.
Yutaka Nagashima joins the team as a postdoc. Welcome, Yutaka!
Our paper on Automated Repair of Heap-Manipulating Programs via SuSLik-style Synthesis will appear at VMCAI 2021.
An extended paper on Distributed Protocol Combinators with an expanded toolset and more case studies has been accepted for publication in Journal of Functional Programming. Now we can do Paxos!
Ilya will present the work on CoSplit at PurPL Seminar Series.
Yunjeong Lee and George Pîrlea join the team as a PhD students at NUS School of Computing. Welcome!
22nd International Conference on Verification, Model Checking, and Abstract Interpretation (VMCAI 2021). Copenhagen, Denmark, January 2021.
Accepted for publication in Journal of Functional Programming in 2021. Cambridge University Press.
Capstone Thesis. Yale-NUS College, 2020. Recipient of Outstanding Yale-NUS Capstone Prize for 2020.
2020 Virtual LLVM Developers' Meeting on the LLVM Compiler Infrastructure, October 2020.
32nd International Conference on Computer-Aided Verification (CAV 2020). Los Angeles, CA, USA, July 2020.
29th European Symposium on Programming (ESOP 2020). Dublin, Ireland, April 2020.
34th ACM SIGPLAN Conference on Object-Oriented Programming Systems, Languages and Applications (OOPSLA 2019). Athens, Greece, October 2019.
MEng Thesis. University College London, 2019
Capstone Thesis. Yale-NUS College, 2019.
Capstone Thesis. Yale-NUS College, 2019.