CoRecursive: Coding Stories

Tech Talks are in-depth technical discussions.

Today Adam talks to Bartosz Milewski. He is the author of a famous blog series, lecture series and now book on Category Theory for programmers.

The world of functional programming is rife with terminology imported from abstract algebra and Category Theory. In fact, it may be one of the most valid criticisms of functional programming is the use of Category-Theoretic terminology that can be unwelcoming to newcomers.

Category theory can also be a tool to teach us to see software development in a different light and it can teach us to build better software. Bartosz is also just an interesting person, if you haven't heard of him yet, you are in for a treat.

Bartosz's Website

Blog Series

Book

Lecture Series

https://corecursive.com/035-bartosz-milewski-category-theory/

Tech Talks are in-depth technical discussions.

How do we create great software? What are the important skills need to properly review a PR? How do you identify assumptions of a code base and the stable contracts of a software module?

Jimmy Koppel is working on his Ph.D. in the field of program synthesis at MIT. He was previously paid 100 thousand dollars to drop out of university by Peter Thiel, but yet still graduated with two degrees.

The most interesting, however, about Jimmy is he is working hard to teach the world how to design better software. Due to his time working on program synthesis, he developed some unique insights into what makes software good, and what makes it bad, and he spends time teaching people his insights.

Three Level of Software

Peter Thiel 20 under 20

Benjamin Franklin Method You are a Program Synthesizer

Jimmy's Coaching Program

Episode Page: https://corecursive.com/036-jimmy-koppel-advanced-software-design/

Tech Talks are in-depth technical discussions.

How do we make JavaScript easier to work with? Chris Krycho has been using typescript to add types to javascript since 2016.

Chris is a software developer at LinkedIn who, at his previous gig, worked on converting one of the largest Ember apps in the world to TypeScript. I was shocked by the size. Chris also loves Rust and types and is a former C and FORTRAN programmers. He hosted a podcast called the New Rustacean, which he has retired from.

Today we talk about TypeScript and when you should use it. We also talk about Language Server Protocols, Rust, working with large codebases, Structural types, row polymorphism and talking code over audio.

• Chris's Blog TypeScript
• New Rustacean
• Chris's Typescript
• Refinement types in TypeScript
• Winning Slowly Podcast

https://corecursive.com/034-chris-krycho-typescript/

Self-driving cars or armed autonomous military robots may make use of the same technologies. In a certain sense, we as software developers are helping to build and shape the future. What does the future look like and are we helping build the right one? Is technology a force for liberty or oppression.

Cory Doctorow is one of my favorite authors and also a public intellectual with a keen insight into the dangers we face a society. In this interview, I ask him how to avoid ending up in a techno-totalitarian society. We also talk about Turing, DRM, data mining and monopolies.

• The coming war on general computation
• Cory's Personal Site
• Radicalized (and other books)
• EFF

Website for Page

Bob Nystrom is the author of Crafting Interpreters. I speak with Nystrom about building a programming language and an interpreter implementation for it. We talk about parsing, the difference between compiler and interpreters and a lot more.

If you are wondering why many languages have hand-rolled parser implementations yet much work on build language implementations focuses on parser and tokenizer generators then Bob's insights will be eye-opening. Also, if you've ever used regexes to pull strings apart into structured data, and I sure have, then Bob's perspective on the simplicity of hand-rolled parsers will certainly open up some new possibilities for you.

Links:

http://craftinginterpreters.com/ http://gameprogrammingpatterns.com/ http://journal.stuffwithstuff.com/

Formal verification and type systems - how do they relate? Niki Vazou is on a mission to bring better formal verification to the masses.

I have done a couple of episodes about dependent types and my feeling is that dependent types are super powerful and have some conceptual simplicity ( Types are a first-class concept ) but are somewhat tricky to wield in practice.

Refinement types are something simpler. A refinement is a predicate that narrows the meaning of a type. What if instead of divide taking two ints, one was Int i where i != 0. This is a refinement type, a type that has been refined, the set of possible values narrowed, using simple predicates.

Niki is the creator of Liquid Haskell, a system that extends Haskell to support refinements. It actually goes farther than that. She has also worked on refinement types in Ruby and explained refinement types to scala community at various conferences, but her heart lies with the Haskell community. We talk about refinement types, theorem proving, formal verification, SMT solvers, and working with GHC.

This interview is also a great place to hear me asking stupid questions of a very smart person. Niki and her work are way outside my comfort bounds but hopefully my struggles to understand the topic will help make the power of refinement types approachable to a wider audience. Ruby developers, js developers, and everyone, refinement types are for you as well.

Links:

• Liquid Haskell Talk
• Programming with Refinement Types
• Liquid Haskell Tutorial
• Niki's Ph.D. Thesis
• Real World Liquid Types
• Refinement Types for Ruby
• Liquid Haskell Proofs
• Refinement Types for Scala 

Can we make databases faster and remove the need for caching reads in an external cache? Can we make a distributed SQL based relational database that outperforms memcached? Jon Gjengset and the PDOS team at MIT CSAIL have done just that with Noria.

Today I talk to Jon about Noria, about building a database in rust and his efforts to teach people intermediate rust via live coding sessions.

Jon was great to talk to. He really was able to explain to me how Noria is able to do what it does and where it is in terms of maturity. The key, besides Rust and evmaps, is that Noria uses materialized views to do query optimization ahead of time, on write. The devil is in the details though, of course. And the details, in this case, are turning declarative SQL into a dataflow program that handles cache updates on new writes.

http://corecursive.com/030-rethinking-databases-with-jon-gjengset/

Show notes:

• Noria Project
• pdos group at MIT

• Noria Paper
• Noria Article
• Jon's Rust Streaming

Andy Hunt is a celebrity in the world of software development. Or at least he is one to me. The Pragmatic Programmer is a classic book on software development book. He is an author of the agile manifesto and started the book company that has published many great books, including several by recent guests.

Today I talk to Andy about how software engineers can get better at thinking and learning. How can we develop this meta-skill and how can being aware of common mistakes our brain make us more productive?

Show notes:

• The Pragmatic Programmer
• Pragmatic Thinking and Learning
• Conglommora

Webpage for Episode

Tech Talks are in-depth technical discussions.

Pat Helland has a wealth of knowledge on building distributed data stores. He has been working on distributed data stores since 1978, when he worked on the tandem fault-tolerant database. Since then he has been involved in many distributed database projects.

Here is the key thing, he is also a master at explaining the key ideas of distributed systems using simple language and practical everyday examples. Can you get married on the phone? How are messaging systems and idempotence like regional offices communicating via fax machine? These are the type of metaphor that Pat uses. Today, Pat sits down with me and teaches me about dealing with data in a distributed, fault tolerant, infinitely scaling world.

Webpage : http://corecursive.com/028-data-pat-heland/

Links:

• Pat's articles ON ACM QUEUE
• Mind your state for your state of mine
• Consistency Eventually
• Standing on Distributed Shoulders of Giants
• The Singular Success of SQL
• Life Beyond Distributed Transactions

What is abstraction? Can we have a precise definition of abstraction that, once understood, makes writing software simpler? Runar has thought a lot about abstraction and how we can choose the proper level of abstraction for the software we write. In this interview, he explains these concepts using examples from the real world, from SQL, from effectful computing and many other areas.

We also talk about how to learn and acquire the skills necessary to understand abstract concepts like very polymorphic code and category theory.

Runar also explains his latest project unison computing and how it uses the correct level of abstraction to rethink several foundation ideas in software development.

Links:

• Constraints Liberate
• Maximally Powerful, Minimally Useful
• Unison Computing

Webpage for show