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A selected list of projects I’ve worked on follows.


Lambdatron is a Clojure-like Lisp interpreter implemented in Swift. It is provided as an OS X command-line application that be run either as a REPL or used to execute code files. The eventual goal is to package it as a library which can be dropped into other applications and used as an embedded scripting language, or used with the REPL as a stand-alone interpreter.

While still a work in progress, Lambdatron already supports a number of useful features. Primitives include booleans, strings, integers, and floating-point values, with more to come. Supported collections include lists, vectors, and hashmaps. Functions are first-class citizens, and when defined can capture values in their environment as closures. Macros are supported, as are syntax-quote, unquote, and unquote-splice. recur can be used with loop to perform iteration, or with functions to perform tail-call optimized recursion. let can be used to define lexically scoped local bindings. A growing standard library and collection of built-in functions provides important core functionality.

Source code and detailed instructions can be found at the project’s GitHub page. Contributions and feedback are welcome!


Hakawai is a iOS library implemented in Objective-C that provides a more powerful UITextView meant for applications where lightweight but powerful text editing capabilities are necessary. It exposes a number of additional convenience APIs, such as block-based transformers for manipulating the text view’s text, as well as a plug-in system that allows the text view’s functionality to be extended in an orderly fashion.

Hakawai’s most powerful feature is an included plug-in enabling the creation of social media ‘mentions’, or text annotations which users create by selecting from a list of options. For example, in the LinkedIn app (for which Hakawai was originally built), users can ‘mention’ other LinkedIn members or companies in an update or comment by typing an ‘@’ symbol. The mentions plug-in is fully-featured, configurable, and generic enough to be used in almost any application. A simple three-method delegate API is all the plug-in requires from the host app.

Check it out here, and read the LinkedIn engineering blog post about it here. If you have the latest version of CocoaPods installed you can also try it immediately using pod try hakawai.