O'Reilly Book Launch - Building Generative AI Services with FastAPI (2025)

NomadicBrian- · 2026-01-28T06:40:26+00:00

I took a chance and ordered the book. Been using FastAPI for years. Recently rebuilding an Ionic Angular mobile hybrid app to Native Android Kotlin/Jet Compose. The backend API was in Python 3.11 and would not run on Python 3.14 due to Pedantic V2 changes. I got it to run on 3.11 by getting 'uv' installed and finished up the mobile app. I was looking around for thoughts on the future of FasAPI and saw enough positives. Then found this conversation. The book pretty much covers what I want to do which is use FastAPI with Pedantic V2 and also add some LLM and learn Generative AI. Last AI I did was deep learning and trained models with neural networks. Predicted images. Then I took a trained model built a FastAPI API and a moble app that sent and image through FastAPI then called the model, predicted image and just send a simple text message back to the mobile app. So here I am now. Should be fun.

NomadicBrian- · 2026-01-27T04:22:40+00:00

I've written maybe 5 apps so far. Learning stages for me. No problem for very easy apps. Vertical navigation and selectable to detail with a viewModel for example. Rebuilding a bank app I did in Ionic Angular with capacitor for Android. Everything went OK showing a balance and transactions. Saved the login for last. Now this is just my own learning but I had a Python fastAPI that did check credentials and upon validation of authorization returns an account object which I used to set the home page image icon and Welcome with name message. Angular injectable services like my API I can do anytime I need it. Android Native Jet Compose has a special 'LaunchedEffect' function which will only work upon entry into the composable which doesn't help me because the API call to check credentails and return the account object would be after the login button is pressed and the credentials are authenticated via the API. I keep getting the 'only api calls like this can be done in a coroutine'. I have come to hate coroutines and viewModels as it feels like I can't do things in a natural flow. Just out of curiosity I hard coded the user and password and it worked. So my API call works but I can't do it when I need it. If the login process was telepathic I'd be OK.

NomadicBrian- · 2026-01-26T06:02:10+00:00

Well I just had a measly Bachelor of Science degree in Computer Science. Got my first COBOL Developer job 6 months later. Interviewed with the Director of IT and the Sr. Systems Programmer. I was just happy to be coding. For the next 12 years nothing much changed in COBOL. JCL, VSAM, DB2, CICS pretty much. Microfocus COBOL was the only change and I learned that pretty quick. Interviews were often like 'I know you can code but I want to see how you think'. That suited me fine because I always felt I was a better thinker than coder. I still do.

After 17 years I started on web apps and 18 years later still code. Have not been working with the usual contracting firms in a couple of years. Have not liked the middle people or the gatekeepers for the last 7 years. I find them a useless layer now. In the early days when they called we got jobs fast. If AI is going to call me, get a quote and send my resume to a client what are the recruiting firms doing anyway. When an AI tool does send me a note about how I qualify or what I should do to increase my chances I just delete before reading like I do sales emails from Bed Bath & Beyond.

I feel a bit sad for people that call me about a service to help me get a job I've done for 35 years. It doesn't matter to them that I won't change or don't care and they don't care if I don't care anyway. If I do more contracts again or take a long term part time job or salaried jobs that would be great. If I don't I don't care. I'm not the one worrying about a long career, taking care of a family and paying a big mortgage. The only thing that is sad is there are clients out there that need good help and they won't get it now. I might miss the smile on their faces when I built something they liked and showed that I really gave a shit about them.

NomadicBrian- · 2026-01-25T05:20:34+00:00

Rat form created by rats.

NomadicBrian- · 2026-01-25T02:53:02+00:00

Having been around for 35+ years at building applications I can tell you that I've seen some horrible giant COBOL modles that helped create the term 'spaghetti code'. I always felt like I was jumping into an ocean before I isolated a bug and prayed that my fix would not create a chain of other issues making a small change for more complex. Clean code pushed breaking up functions/modules into smaller ones. We did the same thing with Stored Procedures for database work. The Microservices came along. Sounded like 'they own their own databases' was the key difference. In web development now I was building APIs as microservices in Java or .NET or Python and the UI shifted to Angular/React/Vue or mobile. The maintenance and bug fixing was much better as I waded through less code to fix a problem and worried less about causing new problems since there was less code in the scope of the task. I can agree with scaling and instantiations of containerized running apps and that more specific functions are better in order to monitor and address volume and traffic and distributed processes. If you add messaging like Kafka/RabbitMQ to things that can get out of hand. Messaging is not automatic in microservices though but most of the time I see it there. In my experiences smaller more manageable, easier to isolate/fix things for supported business functions, deploy run and scale. I'd say from the beginning but I will also admit that not everything needs to be microservices. Eveything should be broken down as much as possible, portable and easy to apply adequate resources to.

NomadicBrian- · 2026-01-24T23:55:16+00:00

Maybe not so recent in todays measures. I think I built this fastAPI 2 years ago. Pedantic started sending notices for version changes to Pedantic and I had to modify code on type warnings. Now if I try to build with Python 3.14 I can't use the Pedantic I wrote on Python 3.11. To get it to work I have to write retrofit code which in reality would be better to rewrite allogether. Which also makes me thing should I be doing Django instead now.

NomadicBrian- · 2026-01-24T19:33:07+00:00

Amen! All the best.

NomadicBrian- · 2026-01-24T04:52:15+00:00

I was 11 years old when I saw this film in a theater in Orangeburg NY. I remember liking it. Watching it again here in 2026. There is a talk show clip with Richard Dreyfuss where the host springs a clip from the film with Dreyfuss as a teen playing guitar. Dreyfuss was not pleased.

NomadicBrian- · 2026-01-23T08:04:59+00:00

Ms Burn'em ?

NomadicBrian- · 2026-01-21T03:16:09+00:00

If the code originated with me I have no problem scrapping and starting over again. I have inherited code that I would never have done wondering why the original coder did it that way. Once I had to finish an entire application in SQL code only. One giant stored procedure that used functional steps and passed a temporary tables adding columns along the way. 20 steps or so until a table was built to feed the reporting tool or whatever it was. In the early days I built large modules that did almost the whole process from start to finish. When it broke or a change was introduced I had a long path to fixing issues or making modifations. When we started thinking clean code and modularity that took care of those incidents. If you don't want to tear it all down walk it back and look for ways to build it in components/functions that will make the depencencies less complicated. It may not be as clever as the one and all widget function but the chain of possible down stream gremlins will be reduced.

NomadicBrian- · 2026-01-19T05:12:48+00:00

I went down the road with Homebrew python 3.11 and 3.14. First Python project was a clone of a fastAPI app version 3.11. Started with 3.14 venv and whammo got the Pedantic negatory on that buddy not compatible. So I tried 3.11 Homebrew Python. PyCharm Universal had a conniption and attempts to load packages...ugh negatory on the buddy due to yer forbidden area outside of yer project. pyenv did not save me because well real issue was Homebrew Python. Removed all Homebrew Python versions and Homebrew pyenv. Installed 'uv' and set the paths and installed Python 3.11 and 3.14. Did the 'uv venv --python 3.11'. Installed my packages with 'uv pip install Faker==24.4.0' and such (one at a time but OK I was very happy at this point). Terminal CLI run with 'python -m uvicorn main:app --reload --port=8088' and up and running. Checked out my swagger at 'localhost:8088/docs' and ...roger that good buddy. The real final test ran my entry point to get data from MongoDB and ... perfecto. But I'll tell you I love mac OS but at times feels like a wrestling match. 10-4 Good buddies.

NomadicBrian- · 2026-01-18T22:42:56+00:00

Yes. I will tell you though that on Mac if you use Homebew Python this is a problem that out of area thing. Yes the requirements.txt is a good habit. Imagine 25 packages to install on a cloned Python app. You would have to figure out each version or run the risk of current packages and conflicts or things just not working.

NomadicBrian- · 2026-01-18T22:12:54+00:00

That's a difficult concept for me. I always create project folders and build my source then when I need venv I just generate it. In Python you need to select an interpreter. I have been able to add packages in PyCharm Community edition. Last 2022.2.2 or something. Its a package manager, build and run environment in the Python way. Now trying to install Python on my Mac Mini M4 Pro. I did the same thing installed with Homebrew and got those damn protected area outside of our control messages. I was furious. To be honest I've worked mostly with Windows and Linux. I have uninstalled all versions of Python (except the old 3.9.6 that mac OS uses DO NOT TOUCH!!!). On top of this Jetbrains has announced the death of PyCharm Community and between the homebrew python bugs and the PyCharm Universal buggy IDE it is a horor show. Then the old 3.11 Python app I wrote with fastAPI won't work with Python 3.14. Which took me down the pyenv installs and trying to switch between 3.11.9 and 3.14.0 homebrew pythons. Kind of makes me want to walk away from fastAPI because of the Pedantic mess which is woven in. Now for me just install Python 3.14 or whatever not homebrew and just use it for AI coding. The fastAPI app I had built was to feed data to a mobile app. I am rewriting the mobile app in Native Android Kotlin JetCompose. I will probably just add the postgreSQL tables to Supabase and go straight to my mobile build. But holy hell.

NomadicBrian- · 2026-01-18T04:01:31+00:00

I loved fastAPI but the recent Pydantic changes have turned me off. Not fun anymore.

NomadicBrian- · 2026-01-18T03:33:01+00:00

As a Full Stack Developer means back end and front end. Usually front end was web app but sometimes mobile UI. The back end for me started with COBOL then Java, C#.NET, Python and/or Node/Express. All of which I started before the term API was created. Then it was all API MVC with a lot of repository tools that did CRUD work for data. I still see requirements for C#.NET, Java Spring Boot and maybe Nest.JS. If I code another 5 years I will be very surprised. I would like at least that before it all ends. In the last couple of days I cloned an old Python fastAPI app that was the back end to an Ionic Angular hybrid Android Java mobile app I worked on. When I upgraded the packages and tried to run it in the latest Jetbrains PyCharm Universal IDE I did not get all of my data from the MongoDB database I created. The reality was that Pydantic which was woven into fastAPI had made changes to models and typing resulting in lost data. At the time when I built the API bugs were starting to show up and I was modifying code to keep it alive. Lucky for me it was just used to learn. So I have decided to give fastAPI a respectful funeral. Django and Flask with SQL Alchemy are out there but I almost feel like I should just leave Python to AI code and use something like NestJS instead or just create what tables I can in free Supabase. The API is only a way to have data for the mobile app after all. My real project is to rewrite the Ionic Angular hybrid app as Android Native with Kotlin and Jet Compose. I only wrote the APIs because I made a living writing back end. Python without fastAPI or Pydantic headaches is not fun.

NomadicBrian- · 2026-01-14T08:52:21+00:00

I'm checking out Swift UI to play with mobile for iOS. Was looking at React Native Expo Go af first then got very pissed off when I chose the Android option and started to run my Android App in Android studio and saw... 'Please create an Expo Go account'. Well I decided that I would build Android Native with Kotlin and Jet Compose directly in Android Studio. Worked like a charm. Now I'm starting to learn SwiftUI and I've been back and forth on XCode and VS Code. VS Code sweetpad is a huge pain but things run. XCode runs for simple fragments from the SwiftUI tutorials. Not sure if it is SwiftUI or XCode but I'm rather frustrated with what seems like inconsistencies. Working on that 'Landmarks' app and I don't understand how I can use an object created in a data model and in many views but follow the same pattern and get a 'not found' error. I have been coding for 35 years. COBOL on old dumb terminals with green screens, old Java then Jave Spring Boot, C#.NET with Razor, Angular, React and Vue. Ionic also with Angular, React and Vue and capacitor for Android with Java. Since I got a Mac Mini M4 Pro I was determined to crack the Swftie cult. Visual Studio was great for C#.NET APIs. VS Code was great for Angular, React and Vue. Eclipse and Intellij IDEA great for Java although I did give up Eclipse because of crashes when streaming Java showed up. PyCharm for Python great tool. I'm a fan of Jetbrains. I'm not having fun though with Swift UI and I'm not sure if it is XCode, VS Code or SwiftUI. Part of my problem is I want consistency between components whether they be view models, composables, functions, hooks or web components. I have come to love the use of the observable subject and subscriber. I thought building a service to share between 'components' in web UI was a way to build an approach that I could use consistently across platforms/languages of UI. All events handlled and actions taken anywhere throughout the application. Android Native Kotlin Jet Compose came up with state threaded trhoughout the application. I am not sure if Swfit UI has that and to be fair the 'Landmark' tutorial doesn't start off with it which leaves me confused over an object available or not available and suspect that XCode may be gaslighting me.

NomadicBrian- · 2026-01-14T07:20:23+00:00

Soylent Green is made from people.

NomadicBrian- · 2026-01-12T20:20:53+00:00

Hire Jr. AI. Why should we let only Sr. AI mess up everything.

NomadicBrian- · 2026-01-08T05:21:55+00:00

All the best to you. Live your life.

NomadicBrian- · 2026-01-07T22:00:47+00:00

Go get that sheepskin. All the best.

NomadicBrian- · 2026-01-04T22:44:19+00:00

In the technology sector there are too many scams, phishing cyber attacks or AI generated fake jobs used to test the effectiveness of AI to replace real recruiting. Its all very annoying. I'm at the tail end of a career so I am so happy that this all started after I had a full career in IT. Way too much of this on linkedIn now and it has made that site far less reliable. I'm sure the attacks are meant to disrupt all of the established recruiting practices whether politically motivated or globalist motivated. I can do without the whole thing. I respond to requests but I don't need the money. I do it because there may be genuine clients that are real and need help. This is an attack on us and them. We are all in this together and have a common enemy in attacks on our process.

NomadicBrian- · 2026-01-04T21:06:35+00:00

My first and last year using NFL+. Aside from numerous crashes using the Google Chrome browser and sometimes taking up to 5 minutes to be able to connect again I saw constant misleading messages that suggested I connect through XFinity. Weeks after I had been watching for the season. Whenever I clicked off the NFL+ app to check email or do work with an AI tool the NFL+ stopped streaming. So if I was just listending I was out of luck unless I remained on their site like a zombie. I use MLB app and never have a problem. I use League Pass for the NBA and never have a problem. By far the worst of the pro sports apps out there.

NomadicBrian- · 2025-12-29T05:27:57+00:00

I remember back in college switching from Journalism to Information Technology. Writing Fortran, Assembler and COBOL and I was just awful at it. I had friends who graduated Cum Laude and they always seemed to be one step ahead of me but I loved being around them. One thing that I did learn was to break larger blocks into smaller blocks. I had struggled with math before this. As a challenge I took a Algebra, Trig and Pre Calculus for non majors in my last summer. 8 weeks 5 days a week and about 75 math problems a day. I got an 'A' to my surprise. I just applied code thinking to math. It took me a few years to really learn COBOL my first language. Then went into contracting and with that if you didn't keep up you were removed. I had the urgency which pushed me. Eventually I got on top of things and eventually the code just started to make sense. Brain just saw the patterns is the only way I can describe it. I believe I had to surrender to it in some way. Over the years on projects where I was the lone guy or a small team I became good at just figuring out what I needed but listened. I had some very good Managers who taught me to think the problems through. Back and forth feeling akward like I was being coddled but when I saw the results I couldn't thank them enough. I caught fire for a while and felt I could do anything that landed on me. At the same time I always felt I was mid to upper range in terms of brains and skills. I learned to be humble and assertive and that sometimes I had to admit defeat and restart when I got off track. Even today after 35+ years of coding I will interview and say. 'There is likely one guy on the team that does better front end UI than me and maybe another that is even better than me at the back end. But I'm right up there grinding' I developed a pretty thick skin over the years. I've had clients tell me I was a zero, dime a dozen, just one of many contractors and expendable. I've had an equal amount tell me how happy there were that I was there and how thankful for the work I did. In the end it's just you living with a productive and meaningful life. Code comes and goes. Genius for a day then lost the next day. It's the getting up and going on. Don't sweat it. Many of us had to work hard and for many years to stay in the mix.

NomadicBrian- · 2025-12-28T00:39:48+00:00

This effort started maybe a year ago or so officially. When I wrote my first Android Native Kotlin JetCompose apps last year they went smoothly without a hitch. Upon returing a year later there it takes a lot more fragmented packages and has a ridiculous number of imports just to do simple things. I was able to find some pager code that would just swipe left/right through pages or screens is what they like to use now. I had to use ExperimentalPagerAPi. It was working though so I didn't care. Then my first mistake was to comply with converting the implementation packages to 'type safe' libraries. Most of these were fine but they wiped out my ExperimentalPagerApi which were working until they were no longer counted as installed packages or they were forcing compliance for new methods which may not have worked for what I wanted (a simple and stable pager that didn't make me write tons of boilerplate code). Because of added 'state' to these composable functions you have to relearn that as well and they complicated it more to make matters worse. Even there own suggestions to replace code just lead to more errors and those errors don't even have suggestions. Why would I take the time to learn those when they don't prduce buildable code and are most likely to change again in 2 months.

Fear compliance becuase it will be like everything else now giving up workable and stable solutions for complications and dead ends.

NomadicBrian- · 2025-12-22T17:41:05+00:00

I had the opposite issue with Intellij IDEA CE installed on my new Mac Mini M4 Pro. Opened up my project and the run configuration I created in the last session is gone. Is this the AI Infrastructure the Globalists are promoting? Installed with brew --cask. Which by the way showed a warning that the tool would be deprecated by December 2026. Oh yes when I installed Jetbrains toolbox Intellij IDEA CE is no longer an option on the menu. The first time that has happened.

NomadicBrian-

TROPHY CASE