#73 Lambda Durable Functions 🔶
This week, our serverless expert is AWS Hero Kristine Armiyants, our spotlight falls on AWS Senior Product Manager Michael Gasch, and we look at the latest AWS service releases, blog posts, and more!
Welcome
In last week’s issue, our serverless expert was AWS Community Builder Darya Petrashka, and our spotlight fell on AWS Hero Matt Lewis!
This week, our serverless expert is AWS Hero Kristine Armiyants, our spotlight falls on AWS Senior Product Manager Michael Gasch, and we look at the latest AWS service releases, blog posts, hints and tips, news and more!
This week’s newsletter is sponsored by Leighton.
💡 A quick note from the author: I just wanted to let everyone know that going forward, the newsletters will be every two weeks, to allow me to curate an even better experience for you all - Lee.
📰 Articles that caught the eye
Here are some stand-out articles I read during the week in the World of Serverless, AI, Engineering and Architecture!
⭐ My favourite article this week is by Davide De Sio comparing Durable Functions to Step Functions:
Matheus das Mercês has a fantastic article titled “AWS Lambda Durable Functions on Hexagonal Architecture: The Pattern You’ve Been Looking For”.
Davide De Sio covers ‘AWS Lambda Durable Functions vs Step Functions: A Real-World Comparison’.
Jeremy Daly has an epic article called ‘Context Engineering for Commercial Agent Systems’.
The Register covers ‘From Agile to AI: Anniversary workshop says test-driven development ideal for AI coding’.
Sai Donepudy has a great article titled ‘The Dark Factory Alternative: From Vibe Coding to Spec-Driven Development’.
Pubudu Jayawardana discusses “Understanding Lambda Tenant Isolation“.
Ran Isenberg asks the question ‘Claude Built My Wix Website in 3 Hours - Is SaaS Dead?‘.
Aaron Sempf has a great article titled ‘From Orchestration to Authority‘.
Kenta Goto has another great CDK article, this time ‘Why is cdk.out (Cloud Assembly) Necessary in AWS CDK?‘.
🎓 Ask the Expert
Each week, I ask a different AWS expert the same three questions to get their personal insights - this week we have AWS Hero Kristine Armiyants:
Opinions are the author’s and do not express the views of their employer.
1. What is one common mistake you see teams making when implementing serverless solutions, and how can they avoid it?
This may be an extreme one but I had a case when a customer spent several thousands of dollars in a month on CloudWatch. The thing was that the developer built a serverless flow that was using CloudWatch and used the request ID as a dimension!
In CloudWatch, every unique combination of dimensions creates a brand new custom metric, which cost $0.30 a month for the first 10.000, and plus the API requests and log ingestion, every single run of that function created a new billable metric.
How to avoid it: Never put the request IDs as a dimension. Neither put them in plaintext logs. Consider using CloudWatch Embedded Metric Format (EMF) which is best for generating cost-effective custom metrics from serverless apps and containers too.
2. Which serverless tool or service are you most excited about right now, and why?
From numerous interesting announcements of re:Invent 2025, I’m really excited about S3 Vectors becoming generally available.
Excited to use it as a vector storage engine for Bedrock knowledge base. Love its simplicity & cost effectiveness.
First there were tables and now vectors: S3 is definitely going in an interesting direction!
3. What is your favourite trick or tip when working with serverless that the readers may find interesting?
I would suggest smart usage of wonderful Step Functions. With standard usage of them you are paying for the number of state transitions and that can easily be quite expensive.
Reserve standard workflows only for business-critical workflows, and my favorite case is like payment processing. The real resilience and all the audit trail that Step functions are giving you for the payments case completely justifies the cost.
✅ Bonus tip: join the hashtag#believeinsls discord! There is a community there to answer any questions you may have without getting overzealous on serverless or without judgment! Check it out!…
🧠 Tips & Tricks
This week’s tip is by AWS in their article ‘6,000 AWS accounts, three people, one platform: Lessons learned‘:
Lots of great tips in this article on how to implement a large-scale account-per-tenant model on AWS, and how that model shifts complexity from service code to platform operations.
🚀 New Releases
Here are the latest and most interesting releases this week in the AWS World:
⭐ My favourite release this week is the AWS Observability Power for Kiro, which I am going to try out this weekend!
Amazon Lightsail expands blueprint selection with a new WordPress blueprint.
Amazon Bedrock batch inference now supports the Converse API format.
Amazon CloudWatch logs centralization rules now support customizable destination log group structure.
Amazon SNS now supports push notifications in the Europe (Spain) Region.
Amazon Cognito enhances client secret management with secret rotation and custom secrets.
AWS Lambda Durable Execution SDK for Java now available in Developer Preview.
Aurora DSQL launches new integrations for Visual Studio Code SQLTools and DBeaver.
AWS launches a playground for interactive Aurora DSQL database exploration.
🔥 Tip: Check out https://aws-news.com/ for the very latest up-to-date serverless releases as they happen, created by the talented AWS Serverless Hero Luc van Donkersgoed.
✖️ Social of the Week
This week's social is by Kelsey Hightower on LinkedIn:
Kelsey always has a way of cutting through the noise and getting to the heart of the matter.
What are your thoughts on this post? What are your own experiences?
Are you looking for a new cloud role and are based in the UK? If so, feel free to reach out to me for a chat about roles at Leighton.
👷🏻 Tools & Frameworks
Check out the latest open-source frameworks, news, and tool updates from the past week.
Bref - Bref 3 is released.
taskmd - Markdown-based task management designed for both humans and AI coding assistants. Store your tasks as .md files with YAML frontmatter, and use the CLI or web interface to manage, visualise, and track your work. Includes a Claude Code plugin for slash command integration.
PR-Agent - The original open-source AI-powered code review agent. It handles PR reviews, improvements, and descriptions using a single LLM call per tool. Platform agnostic across GitHub, GitLab, BitBucket, and Azure DevOps, and supports multiple AI models.
AWS MCP Server Deployment Agent SOPs - AWS has launched deployment Standard Operating Procedures (SOPs) available in the AWS MCP Server. These automated procedures let you deploy web applications to your AWS account using natural language prompts from any MCP-compatible IDE, including Kiro, Cursor, and Claude Code. It generates CDK infrastructure, deploys CloudFormation stacks, and creates CI/CD pipelines with recommended security best practices.
mmdflux - Render diagrams as Unicode text, ASCII text, SVG, or JSON. Supports Mermaid syntax and is built for diagram-as-code pipelines with fast rendering, terminal-friendly output, linting, and machine-readable graph data for tooling and agents.
PR Lens - AI-powered GitHub PR code reviewer for teams. It is codebase-aware, injecting co-change history, directory siblings, and paired test files into every review so the AI understands context beyond the diff. Supports Anthropic Claude and OpenAI GPT-4o, and stores team review history in a shared GitHub Gist with zero infra.
aws-lambda-env-modeler - v3 is out! AWS-Lambda-Env-Modeler is a Python library designed to simplify the process of managing and validating environment variables in your AWS Lambda functions.
😂 Just for Fun
This week’s “just for fun” post is by Abdirahman Jama on LinkedIn:
Geez, this is the kind of ‘Dad Joke’ I usually make!
🎙️ YouTube & Podcasts
Here are some of my favourite videos and podcasts this week covering serverless, AI, architecture, and software engineering.
⭐ My favourite video this week was a video I missed 3 weeks ago from James Eastham on Immutable Patterns of System Design!
Adrian Cockcroft asks the question ‘AI Agents Will Do What Cloud Did to Ops - Are You Ready?‘.
The Modern Software Engineering channel asks the question ‘Testing in Production” Actually the Safest Way to Ship?‘.
Aleksander Stensby covers ‘10 Tips To Level Up Your AI-Assisted Coding‘.
James Eastham covers ‘Immutable Patterns of System Design; From Monolith to Agentic AI’ at NDC London 2026.
Lennys Podcast chats with the ‘Cisco President on the AI revolution‘.
Thomas Coopman at DDD Europe 2025 covers ‘Scaling Teams with Ownership‘ in this short video.
Mitchell Hashimoto’s “new way of writing code” on the Pragmatic Engineer.
The Prime and The Standup covers “AI Personal Assistants are ruining people lives”.
The vBrownBag talks through “AI Agents Made Simple: Everything You Need to Know“.
Weekly Case Study 🔍
This week’s case study is by Mercado Libre on AWS:
Mercado Libre, Latin America’s largest e-commerce platform, partnered with AWS Partner Mutt Data to develop GenAds, an AI-powered tool that empowers small and long-tail sellers to quickly go to market with visually impactful product listings.
Leveraging Stability AI’s Stable Diffusion model in Amazon Bedrock, the tool creates contextualised images that place products in visually appealing backgrounds, refining details like reflections and shadows for professional-grade quality. The system uses Anthropic’s Claude 3 Sonnet to generate prompts, stores assets in Amazon S3, and indexes them in Amazon DynamoDB.
Weekly, category-based backgrounds are created and daily selection processes identify popular items for banner generation. Only the most visually engaging and technically precise images make the final cut, adhering to strict advertising parameters. This automated approach reduces the burden on sellers and accelerates the production of impactful ads in the competitive e-commerce space.
🗣️ Inspirational Quotes and Thoughts
This week’s inspirational quote or thought is by Derek J. de Solla Price (Price’s Law):
“The square root of the number of people in a domain do 50% of the work.“
- Derek J. de Solla Price
The law essentially means that in a company of 100, 10 people do half of the major/important work.
In software, these "vital few" are usually the architects or senior devs who understand the entire codebase. If one of these people leaves (or gets "burned out"), the project doesn't just slow down by 10%; it can effectively grind to a halt because the remaining 90% of the staff lacks the tribal knowledge to navigate the core logic.
What are your own thoughts and experiences of this quote? Feel free to leave a comment below.
🗳️ Poll of the Week
In last week’s poll, we asked the question, “How much do you typically pay for online courses?”
Interestingly, 50% said $10-$50, and the other 50% said $100-$200. Personally, I am happy to pay anywhere up to $300 for a great online course.
This week, we ask the question: “You’re starting a brand-new project on AWS today, what is your ‘Default’ data store?”
Please feel free to leave a comment below on your answer.
📅 Serverless Events
The following serverless events are upcoming, so mark your calendars.
ACD Romania - 23rd April 2026.
ACD Chennai - 7th March 2026.
ACD Slovakia - 11th March 2026.
ACD Pune - 21st March 2026.
ACD Romania - 23rd April 2026.
ACD Athens - 28th April 2026.
ACD Türkiye - 9th May 2026.
AWS Comsum Birmingham - 4th June 2026.
Would you happen to have any upcoming events that you would like to highlight? Message me below!
⭐ Spotlight
This week’s spotlight falls on AWS Senior Product Manager Michael Gasch!
Michael is a Senior Product Manager at AWS within the Serverless organisation, where he works on services like Amazon EventBridge and AWS Lambda.
He is obviously deeply passionate about all things distributed, streaming, and event-driven systems (and has answered many of my questions over the years, sending me articles and information to always back up suggestions - so a personal thank you from me, Michael!).
Many of you will recognise Michael from his fantastic deep dive session at re:Invent 2025 alongside Eric Johnson, where they unveiled AWS Lambda Durable Functions to the world. Check it out below:
His work is always helping shape the future of serverless orchestration and event-driven architectures on AWS, and he is also an all round great guy, and I have been lucky to meet him a few times.
Thank you for everything you do for our amazing AWS community, Michael!
Thank you for reading the latest Serverless Advocate Newsletter!
If you want to find out a little more about me, please have a look at:
https://www.serverlessadvocate.com/
See you next time,
Lee
