In this podcast, Michael Stiefel spoke with Justin Sheehy about how to safely put software into production without creating production incidents. Among the topics discussed were the futility of root cause analysis, and the importance of having a shared language for discussing incidents. This discussion included the need for software to be malleable as well as observable, and noted the fact that there are no pure technology decisions, every one of them is a business decision. They also discussed how the growth and use of artificial intelligence poses a major problem for the ability of engineers to understand and fix production incidents.

Read a transcript of this interview: http://bit.ly/4o7iJsW

Subscribe to the Software Architects’ Newsletter for your monthly guide to the essential news and experience from industry peers on emerging patterns and technologies:
https://www.infoq.com/software-architects-newsletter 

Upcoming Events:

InfoQ Dev Summit Munich (October 15-16, 2025)
Essential insights on critical software development priorities.
https://devsummit.infoq.com/conference/munich2025

QCon San Francisco 2025 (November 17-21, 2025)
Get practical inspiration and best practices on emerging software trends directly from senior software developers at early adopter companies.
https://qconsf.com/ 

QCon AI New York 2025 (December 16-17, 2025)
https://ai.qconferences.com/

QCon London 2026 (March 16-19, 2026)
https://qconlondon.com/

The InfoQ Podcasts: 
Weekly inspiration to drive innovation and build great teams from senior software leaders. Listen to all our podcasts and read interview transcripts:

- The InfoQ Podcast https://www.infoq.com/podcasts/ 
- Engineering Culture Podcast by InfoQ https://www.infoq.com/podcasts/#engineering_culture 
- Generally AI: https://www.infoq.com/generally-ai-podcast/ 

Follow InfoQ:
- Mastodon: https://techhub.social/@infoq 
- X: https://x.com/InfoQ?from=@ 
- LinkedIn: https://www.linkedin.com/company/infoq/
- Facebook: https://www.facebook.com/InfoQdotcom#
- Instagram: https://www.instagram.com/infoqdotcom/?hl=en
- Youtube: https://www.youtube.com/infoq
- Bluesky: https://bsky.app/profile/infoq.com


Write for InfoQ: Learn and share the changes and innovations in professional software development.
- Join a community of experts.
- Increase your visibility.
- Grow your career.
https://www.infoq.com/write-for-infoq

Transcript

Safely Changing Software to Avoid Incidents: A Conversation with Justin Sheehy

Asgaut Mjølne Söderbom and Ola Hast, two developers with Sparebank1 speak about their journey towards continuous deployment and pair programming. During the conversation, they share how they use the "waste clock" to identify areas of improvement or how TDD helps them deliver high-quality code.

Read a transcript of this interview: https://bit.ly/4lNvYgI

Subscribe to the Software Architects’ Newsletter for your monthly guide to the essential news and experience from industry peers on emerging patterns and technologies:
https://www.infoq.com/software-architects-newsletter 

Upcoming Events:

InfoQ Dev Summit Munich (October 15-16, 2025)
Essential insights on critical software development priorities.
https://devsummit.infoq.com/conference/munich2025

QCon San Francisco 2025 (November 17-21, 2025)
Get practical inspiration and best practices on emerging software trends directly from senior software developers at early adopter companies.
https://qconsf.com/ 

QCon AI New York 2025 (December 16-17, 2025)
https://ai.qconferences.com/

QCon London 2026 (March 16-19, 2026)
https://qconlondon.com/

The InfoQ Podcasts: 
Weekly inspiration to drive innovation and build great teams from senior software leaders. Listen to all our podcasts and read interview transcripts:

- The InfoQ Podcast https://www.infoq.com/podcasts/ 
- Engineering Culture Podcast by InfoQ https://www.infoq.com/podcasts/#engineering_culture 
- Generally AI: https://www.infoq.com/generally-ai-podcast/ 

Follow InfoQ:
- Mastodon: https://techhub.social/@infoq 
- X: https://x.com/InfoQ?from=@ 
- LinkedIn: https://www.linkedin.com/company/infoq/
- Facebook: https://www.facebook.com/InfoQdotcom#
- Instagram: https://www.instagram.com/infoqdotcom/?hl=en
- Youtube: https://www.youtube.com/infoq
- Bluesky: https://bsky.app/profile/infoq.com


Write for InfoQ: Learn and share the changes and innovations in professional software development.
- Join a community of experts.
- Increase your visibility.
- Grow your career.
https://www.infoq.com/write-for-infoq

Continuous Deployment and Pair Programming for Lean Software Delivery Even Without Jira

In this podcast episode, speakers from the upcoming InfoQ Dev Summit Munich 2025 tackle the practical challenges facing European developers caught between regulatory pressures and technological realities. The panel discusses trade-offs between using US cloud providers versus emerging European alternatives, exploring cloud-agnostic architecture strategies, the implications of data sovereignty, and why digital independence doesn't mean technological isolation.

Read a transcript of this interview: https://bit.ly/46vNSQj

Subscribe to the Software Architects’ Newsletter for your monthly guide to the essential news and experience from industry peers on emerging patterns and technologies:
https://www.infoq.com/software-architects-newsletter 

Upcoming Events:

InfoQ Dev Summit Munich (October 15-16, 2025)
Essential insights on critical software development priorities.
https://devsummit.infoq.com/conference/munich2025

QCon San Francisco 2025 (November 17-21, 2025)
Get practical inspiration and best practices on emerging software trends directly from senior software developers at early adopter companies.
https://qconsf.com/ 

QCon AI New York 2025 (December 16-17, 2025)
https://ai.qconferences.com/

QCon London 2026 (March 16-19, 2026)
https://qconlondon.com/

The InfoQ Podcasts: 
Weekly inspiration to drive innovation and build great teams from senior software leaders. Listen to all our podcasts and read interview transcripts:

- The InfoQ Podcast https://www.infoq.com/podcasts/ 
- Engineering Culture Podcast by InfoQ https://www.infoq.com/podcasts/#engineering_culture 
- Generally AI: https://www.infoq.com/generally-ai-podcast/ 

Follow InfoQ:
- Mastodon: https://techhub.social/@infoq 
- X: https://x.com/InfoQ?from=@ 
- LinkedIn: https://www.linkedin.com/company/infoq/
- Facebook: https://www.facebook.com/InfoQdotcom#
- Instagram: https://www.instagram.com/infoqdotcom/?hl=en
- Youtube: https://www.youtube.com/infoq
- Bluesky: https://bsky.app/profile/infoq.com


Write for InfoQ: Learn and share the changes and innovations in professional software development.
- Join a community of experts.
- Increase your visibility.
- Grow your career.
https://www.infoq.com/write-for-infoq

Sovereign Clouds, Hyperscalers and European Alternatives: InfoQ Dev Summit Munich 2025 Preview

Laurent Doguin and Geoffroy Couprie discuss their pioneering work with Wasm on the infrastructure side. They walk us through the benefits and challenges of building a platform over WebAssembly and why it’s the safer alternative to containers.

Read a transcript of this interview: http://bit.ly/3HheBWx

Subscribe to the Software Architects’ Newsletter for your monthly guide to the essential news and experience from industry peers on emerging patterns and technologies:
https://www.infoq.com/software-architects-newsletter 

Upcoming Events:

InfoQ Dev Summit Munich (October 15-16, 2025)
Essential insights on critical software development priorities.
https://devsummit.infoq.com/conference/munich2025

QCon San Francisco 2025 (November 17-21, 2025)
Get practical inspiration and best practices on emerging software trends directly from senior software developers at early adopter companies.
https://qconsf.com/ 

QCon AI New York 2025 (December 16-17, 2025)
https://ai.qconferences.com/

QCon London 2026 (March 16-19, 2026)
https://qconlondon.com/

The InfoQ Podcasts: 
Weekly inspiration to drive innovation and build great teams from senior software leaders. Listen to all our podcasts and read interview transcripts:

- The InfoQ Podcast https://www.infoq.com/podcasts/ 
- Engineering Culture Podcast by InfoQ https://www.infoq.com/podcasts/#engineering_culture 
- Generally AI: https://www.infoq.com/generally-ai-podcast/ 

Follow InfoQ:
- Mastodon: https://techhub.social/@infoq 
- X: https://x.com/InfoQ?from=@ 
- LinkedIn: https://www.linkedin.com/company/infoq/
- Facebook: https://www.facebook.com/InfoQdotcom#
- Instagram: https://www.instagram.com/infoqdotcom/?hl=en
- Youtube: https://www.youtube.com/infoq
- Bluesky: https://bsky.app/profile/infoq.com

Write for InfoQ: Learn and share the changes and innovations in professional software development.
- Join a community of experts.
- Increase your visibility.
- Grow your career.
https://www.infoq.com/write-for-infoq

Is WebAssembly the Secure, Efficient Alternative Everybody was Waiting for?

Andrew Lamb, a veteran of database engine development, shares his thoughts on why Rust is the right tool for developing low-latency systems, not only from the perspective of the code’s performance, but also looking at productivity and developer joy. He discusses the overall experience of adopting Rust after a decade of programming in C/C++.

Read a transcript of this interview: http://bit.ly/45qi4eK

Subscribe to the Software Architects’ Newsletter for your monthly guide to the essential news and experience from industry peers on emerging patterns and technologies:
https://www.infoq.com/software-architects-newsletter 

Upcoming Events:

InfoQ Dev Summit Munich (October 15-16, 2025)
Essential insights on critical software development priorities.
https://devsummit.infoq.com/conference/munich2025

QCon San Francisco 2025 (November 17-21, 2025)
Get practical inspiration and best practices on emerging software trends directly from senior software developers at early adopter companies.
https://qconsf.com/ 

QCon AI New York 2025 (December 16-17, 2025)
https://ai.qconferences.com/

QCon London 2026 (March 16-19, 2026)
https://qconlondon.com/

The InfoQ Podcasts: 
Weekly inspiration to drive innovation and build great teams from senior software leaders. Listen to all our podcasts and read interview transcripts:

- The InfoQ Podcast https://www.infoq.com/podcasts/ 
- Engineering Culture Podcast by InfoQ https://www.infoq.com/podcasts/#engineering_culture 
- Generally AI: https://www.infoq.com/generally-ai-podcast/ 

Follow InfoQ:
- Mastodon: https://techhub.social/@infoq 
- X: https://x.com/InfoQ?from=@ 
- LinkedIn: https://www.linkedin.com/company/infoq/
- Facebook: https://www.facebook.com/InfoQdotcom#
- Instagram: https://www.instagram.com/infoqdotcom/?hl=en
- Youtube: https://www.youtube.com/infoq
- Bluesky: https://bsky.app/profile/infoq.com


Write for InfoQ: Learn and share the changes and innovations in professional software development.
- Join a community of experts.
- Increase your visibility.
- Grow your career.
https://www.infoq.com/write-for-infoq

Why Rust Will Help You Deliver Better Low-latency Systems and Happier Developers

Marcin Grzejszczak, a veteran of observability spaces, discusses the current state of the space, including its evolution and the fine-grained details of how to instrument your system to capture all relevant information at every level - both inside services and between services communication.

Read a transcript of this interview: http://bit.ly/4mDTkFW

Subscribe to the Software Architects’ Newsletter for your monthly guide to the essential news and experience from industry peers on emerging patterns and technologies:
https://www.infoq.com/software-architects-newsletter 

Upcoming Events:

InfoQ Dev Summit Munich (October 15-16, 2025)
Essential insights on critical software development priorities.
https://devsummit.infoq.com/conference/munich2025

QCon San Francisco 2025 (November 17-21, 2025)
Get practical inspiration and best practices on emerging software trends directly from senior software developers at early adopter companies.
https://qconsf.com/ 

QCon AI New York 2025 (December 16-17, 2025)
https://ai.qconferences.com/

QCon London 2026 (March 16-19, 2026)
https://qconlondon.com/

The InfoQ Podcasts: 
Weekly inspiration to drive innovation and build great teams from senior software leaders. Listen to all our podcasts and read interview transcripts:

- The InfoQ Podcast https://www.infoq.com/podcasts/ 
- Engineering Culture Podcast by InfoQ https://www.infoq.com/podcasts/#engineering_culture 
- Generally AI: https://www.infoq.com/generally-ai-podcast/ 

Follow InfoQ:
- Mastodon: https://techhub.social/@infoq 
- X: https://x.com/InfoQ?from=@ 
- LinkedIn: https://www.linkedin.com/company/infoq/
- Facebook: https://www.facebook.com/InfoQdotcom#
- Instagram: https://www.instagram.com/infoqdotcom/?hl=en
- Youtube: https://www.youtube.com/infoq
- Bluesky: https://bsky.app/profile/infoq.com


Write for InfoQ: Learn and share the changes and innovations in professional software development.
- Join a community of experts.
- Increase your visibility.
- Grow your career.
https://www.infoq.com/write-for-infoq

Observability in Java with Micrometer - a Conversation with Marcin Grzejszczak

In this episode, Suhail Patel joins Thomas Betts for a discussion about growing yourself as your company grows. When he started at Monzo, Patel was one of four engineers on the then new platform team–there are now over 100 people. The conversation covers how to thrive when the company and the systems you’re building are going through major growth.

Read a transcript of this interview: http://bit.ly/41zbtMO

Subscribe to the Software Architects’ Newsletter for your monthly guide to the essential news and experience from industry peers on emerging patterns and technologies:
https://www.infoq.com/software-architects-newsletter 

Upcoming Events:

InfoQ Dev Summit Munich (October 15-16, 2025)
Essential insights on critical software development priorities.
https://devsummit.infoq.com/conference/munich2025

QCon San Francisco 2025 (November 17-21, 2025)
Get practical inspiration and best practices on emerging software trends directly from senior software developers at early adopter companies.
https://qconsf.com/ 

QCon AI New York 2025 (December 16-17, 2025)
https://ai.qconferences.com/

QCon London 2026 (March 16-19, 2026)
https://qconlondon.com/

The InfoQ Podcasts: 
Weekly inspiration to drive innovation and build great teams from senior software leaders. Listen to all our podcasts and read interview transcripts:

- The InfoQ Podcast https://www.infoq.com/podcasts/ 
- Engineering Culture Podcast by InfoQ https://www.infoq.com/podcasts/#engineering_culture 
- Generally AI: https://www.infoq.com/generally-ai-podcast/ 

Follow InfoQ:
- Mastodon: https://techhub.social/@infoq 
- X: https://x.com/InfoQ?from=@ 
- LinkedIn: https://www.linkedin.com/company/infoq/
- Facebook: https://www.facebook.com/InfoQdotcom#
- Instagram: https://www.instagram.com/infoqdotcom/?hl=en
- Youtube: https://www.youtube.com/infoq
- Bluesky: https://bsky.app/profile/infoq.com


Write for InfoQ: Learn and share the changes and innovations in professional software development.
- Join a community of experts.
- Increase your visibility.
- Grow your career.
https://www.infoq.com/write-for-infoq

Scaling Systems, Companies, and Careers with Suhail Patel

In this episode of the podcast, members of the InfoQ editorial staff and friends of InfoQ discuss the current trends in the domain of AI, ML and Data Engineering.

One of the regular features of InfoQ are the trends reports, which each focus on a different aspect of software development. These reports provide the InfoQ readers and listeners with a high-level overview of the topics to pay attention to this year.

InfoQ AI, ML and Data Engineering editorial team met with external guests to discuss the trends in AI and ML areas, and what to watch out for the next 12 months. In addition to the written report and trends graph, this podcast provides a recording of a discussion where expert panelists discuss how innovative AI technologies are disrupting the industry.

Read a transcript of this interview: http://bit.ly/4nRpvlF

Subscribe to the Software Architects’ Newsletter for your monthly guide to the essential news and experience from industry peers on emerging patterns and technologies:
https://www.infoq.com/software-architects-newsletter 

Upcoming Events:

InfoQ Dev Summit Munich (October 15-16, 2025)
Essential insights on critical software development priorities.
https://devsummit.infoq.com/conference/munich2025

QCon San Francisco 2025 (November 17-21, 2025)
Get practical inspiration and best practices on emerging software trends directly from senior software developers at early adopter companies.
https://qconsf.com/ 

QCon AI New York 2025 (December 16-17, 2025)
https://ai.qconferences.com/

QCon London 2026 (March 16-19, 2026)
https://qconlondon.com/

The InfoQ Podcasts: 
Weekly inspiration to drive innovation and build great teams from senior software leaders. Listen to all our podcasts and read interview transcripts:

- The InfoQ Podcast https://www.infoq.com/podcasts/ 
- Engineering Culture Podcast by InfoQ https://www.infoq.com/podcasts/#engineering_culture 
- Generally AI: https://www.infoq.com/generally-ai-podcast/ 

Follow InfoQ:
- Mastodon: https://techhub.social/@infoq 
- X: https://x.com/InfoQ?from=@ 
- LinkedIn: https://www.linkedin.com/company/infoq/
- Facebook: https://www.facebook.com/InfoQdotcom#
- Instagram: https://www.instagram.com/infoqdotcom/?hl=en
- Youtube: https://www.youtube.com/infoq
- Bluesky: https://bsky.app/profile/infoq.com


Write for InfoQ: Learn and share the changes and innovations in professional software development.
- Join a community of experts.
- Increase your visibility.
- Grow your career.
https://www.infoq.com/write-for-infoq

AI, ML, and Data Engineering InfoQ Trends Report 2025

Software supply chain veteran Brian Fox unpacks the security implications of the new EU Cyber Resilience Act and its profound impact on open-source projects. He reveals the hidden infrastructure risks threatening open-source projects and shares insights for senior software leaders navigating this regulatory landscape.

Read a transcript of this interview: http://bit.ly/46nxjUM

Subscribe to the Software Architects’ Newsletter for your monthly guide to the essential news and experience from industry peers on emerging patterns and technologies:
https://www.infoq.com/software-architects-newsletter 

Upcoming Events:

InfoQ Dev Summit Munich (October 15-16, 2025)
Essential insights on critical software development priorities.
https://devsummit.infoq.com/conference/munich2025

QCon San Francisco 2025 (November 17-21, 2025)
Get practical inspiration and best practices on emerging software trends directly from senior software developers at early adopter companies.
https://qconsf.com/ 

QCon AI New York 2025 (December 16-17, 2025)
https://ai.qconferences.com/

QCon London 2026 (March 16-19, 2026)
https://qconlondon.com/

The InfoQ Podcasts: 
Weekly inspiration to drive innovation and build great teams from senior software leaders. Listen to all our podcasts and read interview transcripts:

- The InfoQ Podcast https://www.infoq.com/podcasts/ 
- Engineering Culture Podcast by InfoQ https://www.infoq.com/podcasts/#engineering_culture 
- Generally AI: https://www.infoq.com/generally-ai-podcast/ 

Follow InfoQ:
- Mastodon: https://techhub.social/@infoq 
- X: https://x.com/InfoQ?from=@ 
- LinkedIn: https://www.linkedin.com/company/infoq/
- Facebook: https://www.facebook.com/InfoQdotcom#
- Instagram: https://www.instagram.com/infoqdotcom/?hl=en
- Youtube: https://www.youtube.com/infoq
- Bluesky: https://bsky.app/profile/infoq.com


Write for InfoQ: Learn and share the changes and innovations in professional software development.
- Join a community of experts.
- Increase your visibility.
- Grow your career.
https://www.infoq.com/write-for-infoq

The Hidden Vulnerability of The Open Source Software Supply Chain: The Underlying Infrastructure

In this podcast, InfoQ spoke with Elena Samuylova from Evidently AI, on best practices in evaluating Large Language Model (LLM) based applications. She also discussed the tools for evaluating, testing and monitoring applications powered by AI technologies.

Read a transcript of this interview:  https://bit.ly/4mHAKvN 

Subscribe to the Software Architects’ Newsletter for your monthly guide to the essential news and experience from industry peers on emerging patterns and technologies:
www.infoq.com/software-architects-newsletter

Upcoming Events:

InfoQ Dev Summit Munich (October 15-16, 2025)
Essential insights on critical software development priorities.
devsummit.infoq.com/conference/munich2025

QCon San Francisco 2025 (November 17-21, 2025)
Get practical inspiration and best practices on emerging software trends directly from senior software developers at early adopter companies.
qconsf.com/

QCon AI New York 2025 (December 16-17, 2025)
ai.qconferences.com/

QCon London 2026 (March 16-19, 2026)
qconlondon.com/

The InfoQ Podcasts:
Weekly inspiration to drive innovation and build great teams from senior software leaders. Listen to all our podcasts and read interview transcripts:

- The InfoQ Podcast www.infoq.com/podcasts/
- Engineering Culture Podcast by InfoQ www.infoq.com/podcasts/#engineering_culture
- Generally AI: www.infoq.com/generally-ai-podcast/

Follow InfoQ:
- Mastodon: techhub.social/@infoq
- X: x.com/InfoQ?from=@
- LinkedIn: www.linkedin.com/company/infoq/
- Facebook: www.facebook.com/InfoQdotcom#
- Instagram: www.instagram.com/infoqdotcom/?hl=en
- Youtube: www.youtube.com/infoq
- Bluesky: bsky.app/profile/infoq.com

Write for InfoQ: Learn and share the changes and innovations in professional software development.
- Join a community of experts.
- Increase your visibility.
- Grow your career.
www.infoq.com/write-for-infoq

Elena Samuylova on Large Language Model (LLM) Based Application Evaluation and LLM as a Judge

On this episode of Eat Sleep Code, guest Todd Motto talks about overcoming JavaScript fatigue. With dozens of new JavaScript frameworks, tools, package managers, and task runners in the ecosystem, how do developers decide on a framework and move forward with a project.

Find the full transcript on Telerik Developer Network

http://developer.telerik.com/content-types/podcast/overcoming-javascript-fatigue/

Ed Charbeneau: Hello, and welcome to Eat Sleep Code, the official Telerik podcast, I'm your host Ed Charbeneau and with me today is Todd Motto. Hi Todd.

Todd Motto: Hey Ed.

00:22 EC: Today we're gonna be talking about JavaScript fatigue. Todd, I brought you on the show today because you are a new team member for Telerik and you're working with JavaScript and Kendo UI, and I thought it'd be a great time to talk about overcoming JavaScript fatigue. And let's talk about that in a moment, but first let's do some introductions, tell us a little bit about yourself and what you do.

00:51 TM: Cool. Yeah, thanks for having me on the show. I'm a new member to the team as you mentioned. I'm over in England, I cover the developer advocate scene in the UK, and parts of Europe and hopefully a little bit further across the pond and over in the US. So yeah, I'm working on the Kendo UI side of things, we'll be diving into the NativeScript as well. There's also the React stuff, and Angular 1 and Angular 2 integrations, so I'll be heavily involved with. So, it's gonna be an exciting year.

02:12 EC: Yeah. Alright man, so we wanted to talk about JavaScript fatigue today. Let's kick it off by explaining what JavaScript fatigue even is.

02:26 TM: Yes. So I think… Well, at the moment, there's this JavaScript fatigue you could probably do a search for it on a Twitter search and get new tweets on it every minute. I think we're just in this JavaScript boom at the moment where there's so many frameworks, and so many new features and tooling, and libraries, and all this stuff that's happening daily and everybody is sort of recommending new things to do. The day before yesterday I was… I'd recently switched over from using Sublime Text to using Atom, and obviously everyone has their own favorite text editor, but everyone's sort of like, "Why don't you try this, why don't you try this, why don't you try this editor instead?" And it's the exact same thing that happens with the JavaScript scene. You might say, "Oh, I've just built this on Angular." And somebody will go, "Why didn't you do in this, why didn't you do it in React? Why didn't you do this? Why didn't you use Flux?" Do you know what I mean? It gives a developer, especially a new developer, to the community like somebody who's come from a jQuery background that builds website to then joining like a software engineering team that builds software in a browser, so web application side of things, to make a jump.

03:37 TM: And then there's this kind of "Which way do I go down?" The path used to be quite clear a couple of years ago, there used to be a couple of frameworks that were sort of the industry leaders and then everybody kinda got a bit smarter and said, "Oh, you know what? I'm actually going to create my own framework or my own version of this framework, and I'm gonna make it 100 times smaller, that's my aim." And then React came out, and then Angular 2 is on its way, and there's all the tooling associated with it. I think instead of just maybe five paths that we had a couple of years ago, we have got 500 paths, and then we've got all the tooling around it. So that's my nutshell definition of JavaScript fatigue, is which way do you go, then when you choose a path, you then go another 500 paths so you can choose either with build tools and back-ends, and web servers, and all this kind of thing.

http://developer.telerik.com/content-types/podcast/overcoming-javascript-fatigue/

Developer Network

Overcoming JavaScript Fatigue

Eat Sleep Code is the Official Telerik Podcast (Telerik by Progress). On Eat Sleep Code you'll hear from industry pros and developers just like you. Topics include all things software development and upcoming tech.

Progress believes in giving back to the developer community and we do this by writing, speaking and staying in touch with the software development community.

Overcoming JavaScript Fatigue

Eat Sleep Code Podcast