Shubhra Kar of StrongLoop talks to Jeff Meyerson about Node.js. Node allows for server-side JavaScript. Shubra and Jeff explore why Node is so important from three standpoints: isomorphic JavaScript, the single-threaded-concurrency model, and the "API economy." Isomorphic JavaScript apps have their own control and viewing logic, but they share the state and specification of the models between client and server. Node's single-threaded event loop concurrency model is ideal for Web programming, where time is traditionally wasted while waiting on I/O. The API economy is dominated by JSON (JavaScript Object Notation), which Node treats as the first-class data model. Shubhra also discusses the changing landscape of the client-server model in a conversation about Browserify, which creates a directory structure in the browser, allowing for conflict management between client and server. Other topics discussed include MongoDB, model-driven development, and V8.

Flavio Junqueira is the author of Zookeeper: Distributed Process Coordination. Flavio and Jeff Meyerson begin by defining ZooKeeper and talking about what ZooKeeper is and isn't. ZooKeeper can be thought of as a patch against certain fallacies of distributed computing: that the network is secure, has zero latency, has infinite bandwidth, and so on. With ZooKeeper, a programmer can be insulated from these problems or at least have a tool to better manage them. More concisely, ZooKeeper is a coordination kernel. It's a set of primitives that abstracts away coordination, leader election, and other troublesome aspects of maintaining a distributed system. Flavio also discusses scaling ZooKeeper, the CAP theorem, and contrasting distributed tools such as Chubby.

Simon Brown, author of Software Architecture for Developers, talks with Sven Johann about using simple sketches to visualize, communicate and document software architecture. The show starts with a consideration of why sketches are more useful than UML and then continues with the explanation of the C4 model (context, containers, components and classes) and how it fits Shneiderman's mantra. Next Brown discusses why the code never matches the diagrams, how frameworks are guilty of this, and what you can do to let the code scream the architecture at you. Finally, it's all about how to create a useful documentation which can also easily maintained and browsed.

Robert Blumen talks with Eric Brewer, who discovered the CAP (consistency, availability, partition tolerance) theorem. The first part of the show focuses on Brewer's original thesis presented at the 2000 ACM Symposium on Principles of Distributed Computing (PODC): What set of problems motivated the formulation of CAP? How was it understood at the time? What are the three types of systems that can exist (or are there only two types)? Is latency the same as a partition? The second half of the show covers Brewer's more recent retrospective article on how things have changed since then: What major insights about CAP have emerged? How has CAP impacted the architecture of real applications? How can architects use the full space of the CAP theorem to arrive at the best designs? Are some types of systems more CAP-friendly? How do CAP systems recover when partitions are healed? The show wraps up with some speculation about the next 16 years.

Eberhard Wolff talks with Eric Evans, the founder of domain-driven design (DDD), about its impact after 10 years. DDD consists of domain-modelling patterns; it has established itself as a sound approach for designing systems with complex requirements. The show covers an introduction to DDD, how the community's understanding of DDD has changed in the last 10 years, the often overlooked component—strategic design, how to use DDD to design microservices, and the connection between microservices and the DDD bounded context. DDD originated during the era of object orientation and relational databases; the show concludes with a look at the recent impact of functional programming and NoSQL on DDD.