%title: Beyond .\*Script
%author: hellerve
%date: 2017-01-15

-> # Beyond .\*Script

-> ## Implementing A Language For The Web

-> Veit Heller
-> Bachelor examination

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-> # Introduction

- JavaScript is _the_ language of the Web
- It is not always the right tool for the job
- Many approaches have been taken to change it
  to fit the users needs

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-> # Introduction

- Mitigations fall into two categories
  - Preprocessors
  - Transpilers
- Caveat: thin wrapper around JavaScript

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-> # Introduction

- zepto-js attempts to build a runtime that is
  foreign to JavaScript while still being compatible
- Features: Functional, Lisp, Macros, Continuations

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-> # Related Work

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-> # Concept Design

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-> # System Design

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-> # Implementation

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-> # Evaluation of the Prototype

- zepto is primarily a platform for prototyping
- Usability was measured during an introductory workshop
- Generally favorable feedback, questions mostly around tooling

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-> # Evaluation of the Prototype

- Addition of the FFI solves performance problems
  - suboptimal, but deemed acceptable for this particular use case
- Features missing affect the compatibility with existing zepto libraries

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-> # Evaluation of the Prototype

- marginally slower than zepto reference in most use cases
- much slower than native JavaScript
  - calling into FFI for performance optimization still necessary

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-> # Summary and Outlook

- zepto-js is as experimental as zepto itself
- with the maturation of zepto and zeps, zepto-js can grow
- tooling still not on par with JavaScript

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-> # Summary and Outlook

- since thesis was written:
  - compiler backend to JavaScript in zepto (node)
  - first stable release of zepto (version 0.9.6)
  - zepto-js development stunted

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-> # Thank you for listening.

-> I am now ready to take questions.