Theses

Theses

If you are interested in writing your thesis at the Software Technology Group, you can simply contact either one of the research assistants or Prof. Mezini. Ideally, you have had a prior look at the list of our current research topics, as most offered theses will cover one of these topics. If you are excited about a listed topic, just contact the topic's supervisor. However, If you are excited about another topic in the area of software engineering / technology that does not match our research topics exactly, please contact us regardless – maybe we can come up with something.

  • 2016/01/04

    Virtual Machine Support for Reactive Programming

    Just in time compiler – interpreter optimization

    Bachelor Thesis, Master Thesis

    Over the last few years, reactive programming (RP) has gained the attention of researchers and practitioners for the potential to express otherwise complex reactive behavior in intuitive and declarative way. Implementations of RP have been proposed in several widespread languages, including Java, Python, Ruby, Javascript and Scala. Recently, concepts inspired by RP have been applied to production frameworks like Microsoft Reactive Extensions (Rx), which received great attention after the success story of the Netflix streaming media provider. Finally, a lot of attention in the frontend developers community is revealed by the increasing number of libraries that implement RP principles, among the others React.js, Bacon.js, Knockout, Meteor and Reactive.coffee.

    Performance remains, however, a major limitation of RP. Most RP implementations are based on libraries where the language runtime is agnostic to reactive abstractions. As a result, a number of aspects like change propagation, dependency tracking and memory management that could be specifically optimized can only benefit from general purpose optimization such as those provided by out of the box just in time compilers. Optimization at the virtual machine level has the potential to address these issues. go

    Supervisor: Dr. Guido Salvaneschi

  • 2015/10/26

    A library for safe Concurrent, Distributed programming

    Bachelor Thesis, Master Thesis

    The STG group at TU Darmstadt has formalised the calculus of structured interactions (CoSI) and the type theory of Essential Multiparty Session Types (EMST) to describe and statically validate safe and deadlock free interactions in concurrent, distributed systems. Multiparty session types is a well-established type theory that is highly attracting the attention of the programming language and software engineering communities.

    The CoSI and EMST aim to establish the foundations of session types and their transition to practice.

    In this project, the bachelor or master student will participate in the design and prototyping of CoSI and global types constructs, devising a library for a mainstream class-based language. The library must support constructs for structuring interactions: session initiation, external and internal choice, matching, and session channels, and the runtime environment that will deal with various characteristics of initiation.The student will use Scribble as a description language for our global types. Scribble is designed based on the ideas and typing strategy underlying the original MST. The amount of work will be properly partitioned in relation to the degree (bachelor or master).

    The ideal student has taken a course or has prior industry or research experience in programming languages and/or compilers. go

    Supervisor: Dr. Andi Bejleri

  • 2015/10/26

    A library for safe composition of decoupled Event-based processes

    Bachelor Thesis, Master Thesis

    The STG group at TU Darmstadt has formalised the E-calculus and a linear type system to model and statically validate composition of decoupled event-based processes, a.k.a. cooperative decoupled event-based processes. In the last decade, event-driven programming has become a major paradigm for developing distributed systems.

    Decoupling makes it possible for new components to get deployed at runtime respectively of existing components that can crash or leave without affecting others and enables modules underlying runtime components to be developed independently, e.g., in publish-subscribe systems, components are not bound to interfaces/modules of other components. However, it is an illusion to believe that one can just run components that were developed independently of each other. At least they need to agree on the content of the messages that they exchange. Yet, the latter alone does not mean that they will accomplish something useful. Hence, there is a need to ensure that they cooperate in a sound manner.

    In this project, the bachelor or master student will participate in the design and prototyping of the E-calculus and its type system as a library for a mainstream programming language, preferably Scala or Java to evaluate the practicality of the E-calculus and its type system. A performance evaluation for the library will be developed. The amount of work will be properly partitioned in relation to the degree (bachelor or master).

    The ideal student has taken a course or has prior industry or research experience in programming languages, event-driven programming, cooperative and publish-subscribe architectures. go

    Supervisor: Dr. Andi Bejleri

  • 2015/09/24

    A theorem prover plugin for Essential Multiparty Session Types

    The STG group at TU Darmstadt has formalised the calculus of structured interactions (CoSI) and the type theory of Essential Multiparty Session Types (EMST) to describe and statically validate safe and deadlock free interactions. Multiparty session types is a well-established type theory that is highly attracting the attention of the programming language and software engineering communities.

    The CoSI and EMST aim to establish the foundations of session types and their transition to practice. The fundamental properties of typed CoSI processes such as subject reduction, communication safety, and progress are established and proved.

    In this project, the bachelor or master student will participate in the design and prototyping of a plugin for a well-established theorem prover (preferably Isabelle or Coq) to assist the formal proofs of soundness for EMST. The plugin will consist in modelling the formal definition of CoSI and its type system in the preferable theorem prover. A test of the plugin will be developed, using the current proofs of soundness of Essential Multiparty Session Types.

    The ideal student has taken a course or has prior industry or research experience in interactive theorem provers (proof assistants) and formal proofs. go

    Supervisor: Dr. Andi Bejleri

  • 2015/08/01

    A dataflow-based programming model for Web applications

    Bachelor Thesis, Master Thesis

    Web applications are traditionally developed implementing the client and the server in different development units. At runtime, JavaScript client code interacts with the (e.g., Java) server code by generating HTTP requests. More advanced solutions, like Ajax, also provide support for the interaction in the other direction – the server can issue events to the client. Separate development of the client and the server requires to explicitly model requests and event handling at each side of the application. Instead, recent advances in programming languages unify the development of the client and the server in the same compilation unit. Developers can use advanced language constructs to specify the placement of computations and the resulting code is then automatically compiled to separate targets.

    This Thesis proposes to unify the programming model described earlier with dataflow languages. Dataflow languages are a programming technique to process event streams in a reactive and declarative way – an approach that has been popularized by the success story for the Netflix backend. The key idea in the Thesis to model in a single code unit complex interaction patterns as dataflow abstractions that seamlessly propagate form the user interface to the server backend. This approach can significantly simplify the development of Web applications and higher the level of abstraction at which programmers reason about client-server interactions. go

    Supervisors: Dr. Guido Salvaneschi, Prof. Dr.-Ing. Mira Mezini

  • 2015/07/30

    A debugging system for reactive programming.

    Bachelor Thesis, Master Thesis

    Reactive languages provide dedicated language-level abstractions for the development of reactive applications, such as event streams and signals. Thanks to this programming technique, reactive applications can be developed in a declarative way, specifying the relation that exists among reactive entities. In contrast to traditional programming paradigms, which require manual updates, with reactive programming, changes are propagated automatically: dependent components (e.g., the GUI) are updated by the runtime when the entities they depend on change (e.g., the data in the model).

    Because of the declarative flavor of reactive programming, traditional debugging tools based on step-by step execution and memory inspection, are hardly effective in this context. For example, in a declarative setting, it is not clear how to “step-over” statements or what “setting a breakpoint” would even mean. go

    Supervisors: Dr. Guido Salvaneschi, Prof. Dr.-Ing. Mira Mezini

  • 2015/07/30

    Eclipse plugin for reactive programming.

    Bachelor Thesis, Master Thesis

    Reactive programming is a recent programming paradigm that specifically supports the development of reactive applications. It provides dedicated language abstractions, like signals and events, that overcome the disadvantages of the traditional Observer pattern.

    Previous research on reactive programming has greatly improved the abstractions available to the developer. Other research areas focused on non-functional properties, like proving safety or time-bound execution of reactive applications.

    Interestingly, supporting reactive applications with dedicated tools and programming environments is a mostly unexplored area. However, the field is extremely promising, since reactive applications exhibit regular patterns that can be easily exploitable by the IDE. go

    Supervisors: Dr. Guido Salvaneschi, Prof. Dr.-Ing. Mira Mezini

  • 2015/07/30

    An empirical study on reactive programming.

    Bachelor Thesis, Master Thesis

    Reactive programming (RP) supports the development of reactive software through dedicated language-level abstractions, like signals and events. Previous research on RP mostly had a programming-languages focus. Researcher extended the available abstractions, made them more interoperable, improved safety using dedicated type systems, and proposed performance optimizations. Over the years, it has been shown that RP overcomes the well-known drawbacks of the Observer design pattern and leads to better software design.

    Unfortunately, when it comes to human factors, the state of the things is less clear. There is preliminary evidence that RP do improve program comprehension in controlled experiments that compare developers using RP against a control group using traditional techniques. However, little is known about why this is the case and which reasoning processes developers adopt when facing a program in the RP style.

    This kind of research challenges have been tackled before thorough experiments that apply the “think loudly” approach, where developers are required to describe the activities they are doing while coding. Collected data allow one to get interesting insights about how developers work and which mental processes guide their choices. go

    Supervisors: Prof. Dr.-Ing. Mira Mezini, Dr. Guido Salvaneschi

  • 2015/07/30

    Language integration of complex event processing

    Bachelor Thesis, Master Thesis

    Complex Event Processing (CEP) is about performing queries over time-changing streams of data. This technology is used to correlate low-level events and generate higher-level events when a certain pattern occurs. Applications include trading software, elaboration from environmental sensors, and intrusion detection through network packets analysis. For example, a CEP system can receive a stream of data from the trading market and perform the following query: “For the five most recent trading days starting today, select all stocks that closed higher than the company X on a given day. Keep the query standing for 20 trading days”. CEP engines, however are usually not integrated in the programming language and simply accept SQL-like queries in the form of strings. In the last few years, parallel line of research investigated event-based languages, that provide ah-hoc support for events. For example C# allows one to define events beside fields and methods in class interfaces. However, this class of languages often simply provides syntactic support for the Observer pattern and does not reach the expressivity of CEP. The goal of the thesis is to achieve high expressivity and integration with the existing abstractions in the same language. go

    Supervisors: Dr. Guido Salvaneschi, Prof. Dr.-Ing. Mira Mezini

  • 2015/03/26

    Build-system migration to Pluto

    Bachelor Thesis, Master Thesis

    https://github.com/pluto-build

    Build systems are used in all but the smallest software projects to invoke the right build tools on the right files in the right order. A build system must be sound (after a build, generated files consistently reflect the latest source files) and efficient (recheck and rebuild as few build units as

    possible). Contemporary build systems provide limited efficiency because they lack support for expressing fine-grained file dependencies. We have defined a novel build system ClearDep that supports sound and optimal incremental builds.

    The goal of this thesis is to develop mechanisms for migrating existing build scripts to our build system ClearDep. A possible roadmap might be:

    • Identify/establish a benchmark of projects that use build system X
    • Implement an abstract builder X in ClearDep
    • Manually migrate some of the projects to use ClearDep
    • Measure build times
    • Tune the ClearDep script to optimize performance
    • Investigate support for automated build-script migration

    The student can freely choose build system X, from which build scripts are migrated to ClearDep.

    For further information, contact Sebastian Erdweg. go

    Supervisors: Dr. rer. nat. Sebastian Erdweg, Prof. Dr.-Ing. Mira Mezini

  • 2014/11/17

    Semi-automatic Verification of the Soundness of Type Systems.

    Bachelor Thesis, Master Thesis

    Type systems shall ensure that correctly typed programs do not get stuck during execution. More formally, type systems shall satisfy certain soundness criteria, for example, progress and preservation (see Pierce). However, proving the soundness of type systems by hand is a tedious and error-prone task. Therefore, it is desirable to have special tool-support for soundness proofs of type systems such that these proofs, or at least large parts of them, can be conducted automatically.

    To this end, we have built a research prototype called Veritas that makes it possible for conducting progress and preservation proofs for type systems for simple programming languages (for example for the simply-typed lambda calculus) in a semi-automatic fashion: Main proof steps of the progress and preservation proofs can be stated within Veritas by hand and can be proven fully automatically by a first-order theorem prover. go

    Supervisors: Prof. Dr.-Ing. Mira Mezini, Sylvia Grewe", M.Sc.

  • 2014/05/21

    Open Analyses Library

    Bachelor Thesis, Master Thesis

    OPAL is a comprehensive library for static analyses that is developed in Scala to facilitate the writing of a wide range of different kinds of analyses. OPAL supports the development of analyses ranging from bug/bug pattern detection up to full-scale data-flow analyses.

    In the context of this project we are always searching for students who are interested in static analysis and want to implement them using Scala. Topics of interest are, e.g., analyses to detect and validate a software's architecture, to find security wholes, to develop need base static analyses such as Call Graph Algorithm or to visualize a software.

    If you are interested in OPAL, do not hesitate to contact Dr. Michael Eichberg. For further information, you can also go to The OPAL Project go

    Supervisors: Dr.-Ing. Michael Eichberg, Prof. Dr.-Ing. Mira Mezini

  • 2014/02/03

    Integrating Language Support for Geometric Algebra Computing into Scala

    Bachelor Thesis, Master Thesis

    GA computing is a new way of geometrically intuitive computing. Based on the underlying Geometric Algebra (GA), it is very easy to compute with geometric objects such as spheres, planes and circles or to handle geometric operations and transformations. For example, the intersection of two spheres, which is a circle, can be simply expressed based on the outer product of the algebra. This technology leads to more compact algorithms for many engineering areas such as computer graphics, computer vision and robotics as well as for simulations, e.g. molecular dynamics simulation.

    The goal of this thesis is to build support for GA computing into Scala using SugarScala. SugarScala is a syntactically extensible variant of Scala where developers can introduce new language features through libraries. Using this technology, this thesis will design and integrate language constructs specific to GA computing. From here, there are two alternative directions:

    • Use lightweight modular staging to compile GA programs to highly-efficient code (the optimizations are well-known), and (time permitting) use Delite to run GA programs in parallel.
    • Design and implement a language on top of the SugarScala GA features that more easily allows experts from computer graphics, computer vision, robotics, or molecular dynamics to express GA programs.

    For further information contact Sebastian Erdweg. This thesis will be co-supervised by Dietmar Hildenbrand. go

    Supervisors: Dr. rer. nat. Sebastian Erdweg, Prof. Dr.-Ing. Mira Mezini