Teaching Apache Kafka Online with Stéphane Maarek

Streaming Audio welcomes Stéphane Maarek (CEO, Datacumulus) on the podcast to discuss how he got started hosting online Apache Kafka® tutorials and teaching on Udemy, the challenges he faces as an instructor, his approach to answering hard questions, and the projects he is currently working on.

EPISODE LINKS

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SEASON 2
Hosted by Tim Berglund, Adi Polak and Viktor Gamov
Produced and Edited by Noelle Gallagher, Peter Furia and Nurie Mohamed
Music by Coastal Kites 
Artwork by Phil Vo 

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Transcript

SPEAKER_01 0:00

Stefan Merrick is a giant of the Kafka community, having created a set of world-class Udemy courses on Kafka and Confluent and other technologies. We talk about how he got started in that business, and we chat about his approach to explaining difficult technical concepts and more on today's episode of Streaming Audio, a podcast about Kafka, Confluent, and the cloud. Hello and welcome back, everyone. I'm Tim Berglund, your host on today's episode of Streaming Audio. And I have with me in the virtual studio, a studio spanning some thousands of miles, Stefan Merrick. Stefan, welcome to the show.

SPEAKER_00 0:42

Hey, thanks, Tim. So happy to be here on Streaming Audio. It's been a while since I wanted to get here, so pretty happy we're doing this now.

SPEAKER_01 0:48

Yeah, me too. This is a true pleasure. So a lot of people, I think, in the Kafka community know your name, but uh what if somebody doesn't? Tell us, tell us about yourself. Who are you? Uh what do you do?

SPEAKER_00 1:00

Oh, shame on them. Um, so um, yeah, I'm I'm Stefan and uh I'm basically a Kafka instructor on the udemi.com platform. And not just that, but mainly this. And so I make uh courses on Apache Kafka and hopefully help people learn uh efficiently and uh quickly all the stuff around Kafka, not just Kafka, but all the ecosystem around it. Um and uh this year I was on the uh Kafka Summit program committee. Uh so helping choose who uh was uh going to talk at the Kafka Summits of London, New York, and San Francisco. So it's been uh really, really fun. Lots of good submissions. And on the side, I do some consulting and more teaching. So pretty busy life.

SPEAKER_01 1:46

Awesome. Awesome. Hey, on the subject of Kafka Summit, I'm glad you brought that up. Listeners, after you're done listening to Stefan, uh at the very end of this podcast, there's gonna be a discount code that you can use to sign up for Kafka Summit. So it has been duly plugged. Uh listen for that code, sign up, come see us. It'll be a great time. Anyway, um I Stefan, I share um a passion for teaching people uh things, and I often find myself gravitating towards situations where I am helping the people who are getting started with a thing. Um and that's so that's uh it's always been um how do I put it, not a concern, but like an interest of mine. How do you do that well? So tell us how you got started in uh Udemy number one. And I know there's more to you than just Udemy. I I I a lot of people know you for that, and I'm gonna reinforce that for like a half an hour here. But how did you get started in Udemy? And um and I I want to spend some time unpacking your approach to teaching.

SPEAKER_00 2:55

So yeah, absolutely. Um, so I got started. I I used to be a consultant in data and analytics, so all things uh reporting, all things analytics. And I moved jobs and I started this job in programming. And I barely knew programming, but I managed to pass uh the tech interviews. And so as soon as I got started, uh my my my teammates were like, you need to know Scala, you need to know AWS, you need to know Kafka. And I was just so overwhelmed. Uh, but I said, okay, I can try. And so I went online and tried to learn a lot about these things. And for me, I found that the most efficient way of learning uh was this thing called Udemy, and I've never heard of it before. Uh, and so I took some courses on Udemy, including on AWS, on Scala, and Kafka, and started from there. Um, but after a while, like I'm an entrepreneur at heart, um, like this is my third venture. Um, I said, okay, maybe I can make my own courses and see if people like the way I explain things. And so I made my first course on is actually on Apache NiFi, just for fun, because it's a tool that I liked and that knew from before. And people really liked the approach. And I said, okay, maybe I can actually teach Kafka because I felt that the course I took on Udemy was not that great at explaining things and actually wrong in several parts. So I made my second course on Apache Kafka, called it Apache Kafka for beginners. And uh that was a really good success because number one, people liked the way I was teaching, and number two, um, they had lots of enrollments, lots of desires from them to get more and more content on Kafka. So that was the start on Udemy, was a happy coincidence, I would say. But it was a really healthy loop between me teaching online and so learning a lot because I needed to know a few things more and looping this back into my work, applying it and learning some more at my work to teach it online. A very, very healthy loop.

SPEAKER_01 4:45

Nice, nice. Um, and is that a thing that like the platform helps with the feedback from students? Is that did you get was it was there a healthy path to hear from the people that you're teaching? Yes.

SPEAKER_00 4:56

Yes. So when you get started, um, students do leave reviews and do ask questions around some things that may not be clear enough for them or they need follow-ups. Uh, and if they're happy, they will leave you a good five-star review, maybe with a comment saying what they liked. And if they're unhappy, they can leave you all the way down to um used to be 0.5 stars, but now it's one stars. And sometimes with a comment saying what they're angry. Uh, nonetheless, you have to take all the feedback in and understand what you can do better and how you can improve. Uh, and definitely my second course of my Kafka for beginners course was not my best, and so this is why I renewed it uh last year because it was popular but yet incomplete and not that good compared to what I was mimicking uh nowadays. And so, yeah, this whole engagement with the community of students, you get that through reading.com. And it's really nice for me to be able to teach online through recorded videos, yet hear from my students from time to time around their concerns or what they want to learn next.

SPEAKER_01 5:52

Right. Because that's that's a thing that's missing off of this kind of online learning, right? It's incredibly scalable. You record some videos once and then a hundred thousand people can watch them. Um, and you don't have to be physically in contact with those 100,000 people, but that feedback path from them, you know, for you to figure out what worked and what didn't, um you know, you you need that. Uh I I find that um when I give a talk, maybe a colleague or a friend afterward will say, How did it go? And I always say, I'm the last guy to ask that, right? I always think it's great. I had a great time, I enjoy doing this, but you sort of have to ask the people in the audience. So it's it's good that you have that feedback path.

SPEAKER_00 6:31

Yeah, and to be fair, you're great when you talk. Here's an outsider feedback. Oh, thank you. Thank you. I appreciate that.

SPEAKER_01 6:37

Um uh but you know, and that is outsider feedback. So that's that's that's better than my opinion. You know, it's more authoritative than my opinion. Um, and you need that. I know, you know, in my growth as a speaker, uh early on, I was I spoke at a series of conferences where there originally there were paper feedback forms that people filled out, and I'd I'd come home from the weekend with this stack of paper, and I'd be happy a little bit and cry a little bit, and you know, later on it moved to uh an iOS app and you just go check online. But you know, that constant stream of feedback is so helpful.

SPEAKER_00 7:13

Yeah, especially especially when you get started. Um, I don't know if you remember your first days of public speaking, uh, but I do remember my first days of online teaching. And and this is when this the support and the feedback is so important because in the first six months, this is how it shapes you as a speaker, as a teacher, or whatever. Um nowadays I do I still get the feedback, I get tons of feedback more. Uh, but it it doesn't really change who I am because I think I've perfected my technique after two and a half years of doing this. Uh, but during the first six months, the first few hundred students who just get uh and talk to me uh and give me feedback, you know, straight, honest, blunt feedback, and you do get that on the internet, even more so than in real life. Um, these these I really I am really thankful for because that helped me shape me as a teacher uh nowadays.

SPEAKER_01 8:01

Yeah, yeah, that's excellent. You do, but it's you get feedback, blunt feedback online, and generally people who are good at software development also tend to be people who uh want to deliver feedback in a clear and direct way. And so you get the the two of those together when you're serving a developer community online. Uh, you know, sometimes the feedback might be a little rough, but that's good. You just have to have thick skin.

SPEAKER_00 8:27

Um yeah, thick skin, thick skin is definitely needed. I remember my first uh one-star reviews. God, I was hurt and depressed.

SPEAKER_01 8:34

I know, I know, and either nobody needs to know what it looked like to be around Stefan that night, right? And my feedback forms that I got at No Fluff Just Stuff in 2010. It it's it's better that like we don't have those here to present on the podcast, or nobody can see what we looked like because it was a little ugly, but you move on and you grow and you learn that that's that's part of the game. Exactly. Do you um do you know what your approach is? So I'm I'm interested in knowing how you approach teaching and explaining. And I uh you do some AWS courses, you do some Kafka courses, and so I don't I don't even care what technology it is, but when you're trying to get new people going on something, um, if I ask you what is your approach, does that question make sense?

SPEAKER_00 9:24

It does make sense, and it's my secret sauce. Um so you want to know the secrets, huh? Um Yes. Okay. I have to deliver this. If you can. I mean, in the political. No, no, no. I I definitely can give give some clues, um, especially for anyone who wants to get started on the teaching side. Um number one is you have to put yourself in the shoes of the learner. Uh it's it's incredibly useful to just actually not know a topic and go through I'm learning it and understand and write down the pain points you have, the questions you have, uh, when you discover some more information that actually clarifies a bit what you had doubts on before and even uh introduces new questions, all that kind of stuff. So, first of all, yeah, put yourself in the shoes of the learner. Then then it's what I call the most difficult part into making a course is the curriculum. I think the rest is so easy afterwards. Not that easy, but much easier. Um the curriculum is how do I break down a complex subject, would it be AWS or Apache Kafka or so many others? How do I break down a very complex topic into bite-sized learnings and that are cohesive together, that follow along uh one after the other, and that do help bring up to date uh and up the upskill the students over time? And that is that is that's what actually takes me the most time. I actually um spend multiple iterations on the course curriculum. I spend a lot of time uh iterating, making sure that it does make sense, moving stuff around, uh doing a walkthrough of that curriculum with myself. And can I actually write uh read it out loud for five minutes and does it make sense? Uh and so all that stuff is you know comes with experience, uh, but I found it to be extremely effective at um at breaking down a concept. And then once it comes to okay, you have the structure and you know where you're going with this, it's all about delivery. And so there are two things in delivery that I really like doing. Um, number one is to explain with diagrams, uh, because I think that uh in the online learning, it's all video and audio-based. And so you need to have really, really good visuals because people need to be able to visualize uh abstract or distributed concepts and they must come to life. So I like to use to just use simple arrows and boxes, that's it. Um and the other thing you need to do is, and this is something you have to perfect over time, is your voice. Um, if someone is watching you for 18 hours straight, this is longer than two seasons of uh Stranger Things on Netflix, um, you have to make sure you're not boring. And this is something that's really, really, really difficult to do, uh, which is how do you keep an audience engaged? Um it applies not only online but also in real life. How do you make sure that people stay engaged? Uh and I think it I think it's actually much easier to do offline because you can see people's reaction as you speak and you can uh tone up or tone down your speech. But online, it's actually much more difficult because you're speaking to your computer, uh, as we're doing right now, you and I, but it's a conversation, so it's easier. But so it's like, how do I make sure that I can emphasize and stress a few words, such as it doesn't sound monotonous, it doesn't sound boring, and people are hooked all the way until the end.

SPEAKER_01 12:30

Uh I love that last point. Um I had an experience that was the first time I recorded a video course. It was boy, uh years ago, seven or eight years ago, maybe. And it was when O'Reilly was first getting into video training, and it was on Git. And I did it, I did it with a colleague, Matthew McCullough. And at the end of the day, it was like six hours of recording. And there were even other people in the room, but most of it was just us teaching to the camera. And I had had experience teaching for that long, like delivering a full day of training or giving conference talks all day or whatever. And I was so much more exhausted at the end of that day on set than a day in an actual classroom. And I think this gets to something you just said that um, which you said a lot of great things that I want to unpack there, but uh you have to keep people engaged with your voice, because in the Udemy format, that's what you have, right? That's you are your voice. Um and you have to use your voice in such a way that that keeps people engaged. I find that when I'm when I'm teaching to a camera, uh, recording audio, even doing a webinar, the fact that I don't have that feedback, right? Because you you said when you got people in the room, you can see them, you can see their eyes, you can see when they're sleepy, you can see when they're bored, see when they're checking their phones, looking at the schedule on the back of their conference badge, all the signs that they are not into you. And what do you do when that happens? Well, you amp it up, you know, you you you do something to get a little bit more exciting, to get their attention a little bit more. Um I've found when it's a camera or a microphone, I'm I'm quite conscious of the fact that I have to keep it interesting, but there's no feedback path. So like I am at maximum engagedness the whole time. And so I guess what I'm saying is lecturing to a room full of people for six hours is difficult and tiring. Recording six hours of audio and video training I think is harder because I I think you know you have to be more engaging more of the time because you don't have that feedback loop. Like you have to assume you're you're fighting for their interest all the time.

SPEAKER_00 14:55

Yeah, yeah, you're absolutely right. Um, it it comes with practice, though. This is because this is something we're not used to doing as humans. Humans talk to one another, they teach to one another, and that it's easy because we do this all day long. When it comes to speaking to a computer, yeah, it's not something we're used to doing. So we have to learn this, and that takes a while. Um, if I go back to my very first class, I hate myself because I think I'm boring. Um, but not hating, you know, but I'm laughing at it. Um after after I think it took me maybe six months or of like heavy recording to just get the technique right. And I still think I'm not that year, uh, that that far ahead in the game. Like if I look at YouTubers, um, or even you, Tim, uh if I look at you, you have you have a great voice and you have oh yes, I'm gonna I'm gonna flatter you. Um, it's you you look at you look at people's experience and you're like, wow, like they're really, really good at putting emotions and they're really, really good at like connecting with their camera, uh, which is like which makes me feel like they're actually connecting with me. And and I'm really impressed when I look at these YouTubers or uh you know more influencer type people who are actually extremely good at uh perfecting this technique of speaking to um their computers and their camera. Yeah.

SPEAKER_01 16:06

Yeah, yeah. Um and I've seen in uh years past, I've seen people who were extremely engaging classroom teachers, like like you know, top 1% uh just great in the classroom and in front of a camera, uh they they were not able to do it, right? It just could just didn't work with that lens there because they're used to interacting with people. Do you think um no that's that's the wrong way to ask the question? Have you ever had any theater training or did you do that in high school or anything like that?

SPEAKER_00 16:41

Ah, good question. Good question. Um I used to be the worst at speaking, and I think I'm still not that great, but I do speak really fast, at least in French. Uh, I'm French, by the way. I do speak really fast in French, and I used to not be able to, I used to be so stressed uh when reading, for example, when I was really young, um, a book in front of my classmates, uh, that kind of stuff. And I think what really freed me was yes, I did took uh I did take improv classes, so improvisation classes, uh, when I was in university, uh type school. And I did it for almost two years, and it really allowed me to just number one, brace the unknown, uh, and number two, speak in front of very, very large audiences of maybe 500 people and not be ashamed of like saying whatever. Um, and that really, really helped me. So it was not really formal classes, it was just like a club. There was no teacher, it was just us practicing and having fun. Uh, but uh I think that counts as somewhat theater classes. I actually would love to take theater classes now and learn and learn some more and perfect my technique around that, or even comedy classes. I'm actually uh nowadays really fascinated at how uh people who are funny can build up tension and then release it just with a tone of their voice. That's something I actually want to master. Um, but yeah, that's my only experience in in public speaking and theater so far. Got it, got it.

SPEAKER_01 18:03

But it's there, and uh I I actually share that desire. I'd love to, you know, there's no time in my life for this, but it would be great to take some acting classes. And I think uh comedy in particular, I think when it comes to um not not online content, but in person, you know, giving talks at conferences and meetups and that kind of thing, I think the best uh, you know, sort of the famous conference speakers are by and large, they're more like stand-up comedians than anything else. Uh I can think of some of them who are you know world-class talents who aren't funny but um and are still world-class and worth knowing. Um, but most of the good ones are funny, you know, like if you're if you're um not even in a talk by say like a Vencat Subramanium, but if you're in a room next to where Vencat Subramanium is giving a talk, you mostly hear laughter from the room. And so I think that connection to stand up is is a real one.

SPEAKER_00 19:02

All right, let's make a pact. Uh you and I are going to do the next season of uh Silicon Valley together and we'll make jokes about Kafka.

unknown 19:10

There you go.

SPEAKER_01 19:12

That's I wanna I I at least want to walk on. Oh, that'd be so great. Um unlikely, but uh if anybody knows Mike Judge, uh you know talk to me on Twitter, my DMs are open. Uh button too. Yeah, right. Get get with Stefan. Talk to us both. Um the um we were talking about using your voice and and using diagrams, and I think that's so important. So if this is a thing, um, and and by the way, this this discipline of creating good instructional video content is a thing that not many people do, but I think that's really good advice. If this is a thing you want to do, you have to learn. If you're if you're if it's just your voice, you have to learn how to use your voice in a way that is interesting. Um and you know, you but uh the thing is we're all actors. If you if you look at the way conversation takes place, if you just listen to two people telling a story about a thing that happened earlier in the day, uh whoever's telling the story is dramatizing the story, and they don't even know they're doing it. You know, they're doing a little bit of acting. And if they could talk into a microphone the way they talk to their friend over coffee, uh then you know that unlocks a lot of that ability to be interesting.

SPEAKER_00 20:29

Yeah. And and one thing I want to just um respond to. So you said about something about quality or somewhat related to quality. Um, it's it's so important to say, yes, I try to have the highest quality content, uh, but quality is always subjective. What is quality? But I'll I'll give you some concrete example, right? Uh number one is to have a good microphone, like the microphone I have right now that I'm speaking into, I've had it for two and a half years and I'm not letting it go. Um that's so important because if you put together a video and people hear you and there's not a good sound quality, they will hate it and they will just go away. Um, number two is uh around the educational contents quality. So diagrams is something that I actually make myself. All the diagrams you'll find in my courses do not exist in the Kafka documentation. They do not exist uh anywhere else. They're original creations of me. And that extra step that I put in creating these quality diagrams really um shines and really helps the student go to the next level. So, you know, not just doing copy and paste of the documentation, but also going above and beyond and putting on your own experience on top of it. And then finally, uh for quality, you need to have preparedness. Uh it's it's not possible to just wing it, it's it just doesn't work. Uh it doesn't flow well, you um uh all the time and you look confused. So you need to be prepared when you start putting together your content. Obviously, you need to be an expert at what you do because otherwise you will never be prepared. And number two, you need to make sure that you know exactly the talking points you're going to have in advance. You don't have to script it, but you have to know where you're going with this and what you want to do. in advance so that the lecture looks like you know what you're doing and looks like you did put a lot of effort into preparing it. And I think when you combine these three things together, you put together educational content that is going to be um really, really appreciated by students, uh viral almost, and and you know worth worth doing. And this is this is if you plan on doing educational content, this is something you cannot um uh budge on. You could you do you cannot not do that. And this is how like luckily thanks to like these principles I've been able to grow from zero students fully unknown to now over 120,000 students around the world and the chance to be on this podcast. So yeah. Yeah.

SPEAKER_01 22:40

Which is amazing. 120 students 120,000 students on yeah it's like it's like a lot of football feats um so um how what uh kind of getting back to the the the technology side of teaching technology um what are some things that have been difficult for you to break down or maybe based on on student reaction difficult for them to learn what what's some of the harder concepts you've tackled?

SPEAKER_00 23:10

Yeah so it's uh it comes to real world examples or labs or hands-on projects um every single student that comes through usually especially on Kafka and AWS not talking about just coding in general but every student that comes through for Kafka for example uh they will have a a use case in mind for their company and if they don't see that use case discussed in your course they won't be very happy to say show me a way to do this this and that and it's like well I'm sorry I can't tailor the course all the way down to your use case because it only matters to you and your small company doesn't matter to the rest of the world. So balancing the act of how wide do I cover versus how deep and how low I cover is extremely difficult and still something that I struggle with every day. Because you always get students saying but what about this? What about that? And what about if I do this or what about if I do that and and when you have a pub sub system such as Kafka there are guidelines and rules but because it can just do anything you want in terms of transporting data across systems, well you can have so many different types of applications. I mean you have some some really straightforward ones like with microservices talking to one another you have some more advanced ones when you use Kafka streams and you have some crazy ones where the New York Times just stores every single image and asset and an article they built on a on the Kafka topic which I think is insane. So all in all it's really really hard to cover every single use case for every single technology. And so knowing where to draw the line is both difficult and painful and this is where usually students get uh problems with my content as well obviously excellent that's that's a really good point.

SPEAKER_01 24:50

And you know I'm fascinated to hear you say that people want to see their use case in the course. That's actually helpful for me because I um I mean I get I get questions when I give talks live um since we don't you know at Confluent we don't have uh public uh open uh online instruction you know there's there's you can get our professional training technical training stuff delivered online uh you know if you're a customer you you register and you pay for that uh and that's that's like really good and complete stuff and there's a certification pathway and it's great. But the stuff that my team makes ends up on YouTube and so we get some YouTube comments but it's not quite the same feedback loop and I don't get that question. I get that question in person ever at the break everybody wants to say well here's what I'm trying to do and could you help me think through this which totally makes sense but I'm fascinated that people expect to see their particular use case in the course.

SPEAKER_00 25:51

Oh man you have no idea what people expect online people buy you that's right you Stefan Merrick are a public utility I turn the knob and the things I want come out you know that's right pretty much have lived man I've lived like the people buy the course on you they usually through like coupons or discount systems so they will spend between 10 and 20 dollars for the course and they expect me to be their how can I say their consultant on demand for free which is like here is my phone number call me because I have a question about my use case and I think your opinion could be really valuable or just call me now. People just people just not how yeah it's it's not scalable not scalable yeah not scalable not free and pretty pretty crazy to be honest what people ask online or like just people sending me their entire uh company's design documents which like I think this is pretty confidential what you sent me like I don't want this but people still do um in the day people wanted to get their job done and I think it's pretty entrepreneurial to try any any possible uh ways of doing so of course I mean they're they're they're like you and me just people struggling to get their job done trying to get help anywhere they can um so that totally makes sense but again yeah that's obviously not that's not the contract between um you and and online students you can't you can't offer uh free consulting um exactly yeah so okay but um that is actually helpful that uh helpful to know that that uh even at the developer level seeing the particular use case matters a lot because I I have that conversation internally a lot with say product marketing folks right and they're they're less focused on the audience you and I uh are a part of and and make it our job to to speak to and they're more focused on talking to buyers right the people with money and in that whole discipline like whatever tech company you are your your product marketing department is laser focused on you know this use case in this vertical these people have money they want to buy our thing it solves their problem and so we talk about that use case because those busy executives who can write checks they just need to hear oh okay it does this thing that's in my world and that's as much as I can think about it.

SPEAKER_01 28:06

So you know they need their use case. And my thing is I often make the case that well you know developers also they just want to understand APIs and they're able to then synthesize a solution within their domain. I think what you're telling me is maybe I'm a little bit wrong about that. And even in our developer audience people still want to see their particular story.

SPEAKER_00 28:25

Yeah I mean people feel confident whenever they see what they're trying to do.

SPEAKER_01 28:28

So yeah that's true. Okay well that's good it's not good to be wrong but it's good to learn that you were wrong which I think I just did so thank you. You're welcome what um so okay we were talking about things that are that are difficult and that's difficult to cover use cases. Has there been any material in Kafka or out of Kafka that it was a struggle to do in the online format? I mean you're you're super good at it and you know if something can be taught I know you can teach it but what what chunks of the technology are hard to do?

SPEAKER_00 29:07

I think the hardest in and the most difficult one for Kafka is around disaster and disaster recovery. Because it's a big it's a big thing right like I have nine Kafka courses 38 hours of video uh covering everything from Kafka Kafka Connect Kafka streams uh confidence schema registry uh setup monitoring security name it's KSQL forgetting one yeah uh case I mean everything right I'm trying to cover everything but there's one thing that I don't cover it's disaster recovery why because I'm a one man per a one man job and I just don't have a production cluster with 20 brokers and a ton of applications running and that I can just happen to make crash on demand you know so that's all like pretty heavy lift yeah people are like what should I do? How should I tune this and how should I uh find out my strategy for disaster and what does it look like and it's like I really can't help you with this because this is this is something you'll have to learn while on the job like there's some stuff that I just can't teach you because everyone's will have different workloads. Maybe your message size will be different maybe your throughput will be different. Maybe the machines you're you're deploying on have different specs. Maybe your network isn't that great maybe your CPU is struggling maybe maybe you misconfigured Kafka maybe your metrics tell you something that I can't tell you and show you in advance. So it's like there's no playbook of how to fix Kafka because if there was uh it'd be amazing and no one would have problems. And so that's that's that's really where people struggle. It's just like Stefan show me like show me stuff going wrong which is like I can't do it because it's really hard to crash Kafka first of all and number two this happens only once and hopefully never but once in a year whatever and yeah that's that's been a struggle for me.

SPEAKER_01 30:46

That that makes a lot of sense you just can't as a there's the the the capital structure of the business is not such that you can set up that infrastructure and build the system that you need to build to simulate the faults and all that kind of stuff.

SPEAKER_00 30:59

That that's uh yeah that's a bummer and again self-promotion if you're a company that has issues with Kafka and want to make some educational content about it I'll be more than happy to help you out with this and get in touch with me. Yes get it he uh Stefan does enter into partnerships for making content so if you've got smarts in that area and you want to share those smarts uh on Udemy this is the guy to talk to so yeah true story the the recently there was the the KSQL course actually um that just came out and um really really good uh collaboration with Simon Aubury uh he's in Australia and he's been writing some really awesome blogs on KSQL and so I got in touch with him and I said would you like to make a course with me because I think that you have more knowledge on KSQL than I'll ever get and he said yes and together we just worked and made the course on KSQL and I think students really like the format um and and yeah that course has been really really amazing and I think people like it. Confluent likes it too so everyone's nice we do.

SPEAKER_01 31:56

This is an officially endorsed uh uh confluent endorsed course by Stefan and Simon Simon is also a great friend of Confluent uh he's done some guest blog posts on our blog and um he's so creative he just comes up with fun stuff to do uh and and that's well well let's get to that in a minute but it about the KSQL course. Yes you should go take that course um and it's uh really good stuff and uh taught by uh a great guy in in partnership with you um but on the topic of fun um that's a that's kind of a Simon thing like he'll tell a story where uh you know there's an airplane that or my cat woke up every night at 2 a.m and I was trying to figure out why did my cat keep waking up and you know 2,000 words later there's a Raspberry Pi cluster and a software defined radio and Kafka and KSQL and he's determined the flight number of the airplane that was flying over his house right um and that's just fun right and even the fact that there's a Raspberry Pi there doesn't need to be a Raspberry Pi in there but we know we're geeks everything is more fun if it's a Raspberry Pi. And just the whole narrative of the cat being involved and and that's you know some of his geniuses the way he teaches these things and let's be honest what he's trying to do is he's trying to show here's how to do this stuff with KSQL. Right here here are some real-time analytic streaming queries you can do with KSQL. But if you just sit somebody down and say hey I'm gonna teach you some real-time analytic queries with KSQL and here is the text um it's hard to learn when it's fun it's a lot easier to learn.

SPEAKER_00 33:37

Yeah exactly and um recently I did something like this um it was on AWS Lambda so not not Kafka. But it's it's a way of running functions in the cloud and it's all serverless and you only pay get paid for what you use. So it's a nice way of deploying stuff. And one of the use cases for AWS Lambda is to have serverless cron jobs so jobs that just get invoked every now and then and do stuff. So you don't need to provision a server you don't need to let your computer running it on. You can just push it on lambda and have your cron job running. And so that's that's it that's the learning I wanted to pass right but what do I want to put on lambda and have it running and and the use case is I'm a huge foodie. Like I love food. It's like one of my passion. And there's this restaurant called Septime in Paris which is one of the best restaurants in the world and I really really wanted to get a reservation but it's been notoriously hard to get a reservation there. And so they had a reservation system online for booking restaurants. And I said you know what I think I can probably write a lender function that will check every two minutes if there's any booking for the month ahead and I did I did write it that function and I did like I did I did check for bookings and what I found out was that they only opened bookings on their reservation system for lunch which is something they definitely not advertise but I had that bit of information. So bottom line I had to pick up the phone and call the restaurant like a normal human and get my reservation for nighttime and hopefully that thankfully there was a really uh easy spot to get for that one night. And I got my reservation but it was you know it was a fun way of playing with AWS lambda and just getting stuff running.

SPEAKER_01 35:13

That is a lot of fun and a great story and um I'm sure a terrific way to impress a dinner date depending on who the dinner date is. Yeah no she was impressed.

SPEAKER_00 35:25

Yeah she's impressed you got a set table at SET team? Yes I wrote a Lambda function for it. Yes that's amazing way too nerdy.

SPEAKER_01 35:35

Yeah yes exactly but again that's uh also endearing um what else are you up to?

SPEAKER_00 35:43

You've mentioned consulting uh tell us tell us about other things and yeah yeah lots lots of stuff happening um on my end so uh definitely the online course is a is a huge part uh of what I do but um I'm just trying to keep stuff up and running right now not trying to actively work on new content because it does take a lot of time um consulting is something I do so I work with uh clients uh on their needs uh usually as clients that I care about about the the type of business they're in because I want to make a difference um so usually short short amount of consulting short uh engagements uh Kafka training in person as well if it's worth it uh if there's a lot of people and they're all very motivated and it's not just like a company people companies people getting credits for their learning and development. What else? I do a lot of things. I'm trying to build a startup on the side but still still in the works. Still in the works. Still in the works can't really mention anything.

SPEAKER_01 36:34

I was I was hoping maybe you could but it'll there'll come a time there'll come a time when it's you can come back.

SPEAKER_00 36:40

There'll come a time I'm taking my time um and also also um developed a a GUI client for Apache Kafka called conductor uh with a K in the middle which is uh something that I think is missing in the ecosystem um and so I'm developing it with another Stefan and it's uh it's a Java desktop application that you download from conductor.io and you can just connect to your cluster and view your topics produce consume consumer groups I mean everything you can do with a CLI and more uh you can do on conductor we even have support for rolling restarts and Cafe Connect and so on and so that that's something really cool that I'm I'm working on and I think that's uh a lot of people I like the tool so far. So excited to see where this is going as well. What do you think your next Udemy course will be ah you probably don't want to think about that right now do you I don't I don't comment on on no there's no there's two exciting things that I'm working on. There is a refresh of the Kafka streams course because the the the the Kafka streams course that I have is quite old now and the APIs has changed and there's new concepts uh such as suppress operator such as other things uh that I think uh are tremendous added value so I'm working on the refresh of the Kafka streams course um that's for the Kafka side uh maybe a refresh of the Kafka Connect course as well uh because I think there's a lot of things that have changed uh with the confident hub uh the CLI and so on and the SMT the the single message transforms that are really cool and then on the AWS side um excited to work on some refresh on my AWS lambda course um a few collabs as well and hopefully I can make two new certification courses soon enough on uh solutions architect professional certification and DevOps professional certification uh which are very very long and hard to do so these kind of things I need to be in the right mindset uh to get on to work and right now it's the summer it's it's like heat wave in Paris it's 42 degrees Celsius outside can't tell you 42 in Paris? Yeah how much Fahrenheit is it? Uh oh that's like 104 I think it's like it's like it's like the valley yeah 100 108 uh Fahrenheit's yeah that's legitimately hot yeah so right now I'm not focusing on making courses I'm more focusing on relaxing and enjoying the summer yeah yeah good good good and and uh trying to stay cool maybe go down south and get some get some water um also you'll be at uh will you be at Kafka summit San Francisco uh actually I will not this is uh this is the one Kafka summit that I will not go to this year um multiple reasons uh but uh number one is that I went to New York and London. And London so that's a lot of Kafka summit. So Kafka overload right here. Yes um and and number two is uh I'm actually moving um to Portugal mid September and this is way too shortly after my move. So yeah trying to get some sun moving down south as you said. Exactly exactly yeah but this is an exciting an exciting um uh roster I mean I I know it because I had to read all the submissions uh and and help choose who's going to speak uh but I think there's some tremendous talks happening at Kafka Summit uh San Francisco and I'll I'll make sure to check out a few uh replays um online awesome and remember listen listen past the uh listen into the outro and you get a discount code if you like the sound of Kafka Summit and you want to sign up uh you can get a discount for being a listener so and you get discounts from my UDB courses right after Tim gives a discount so you know lots of discounts coming at the end of this so many discounts at the end of this so many. Do we um do we have a discount code for that? Yeah yeah um I'll give it to you right now then um it's uh streaming underscore audio and it works for any of the Kafka courses I have so you go to udimi.com and just search for Kafka and you'll find my courses and you type streaming underscore audio uh all caps streaming underscore all caps audio and you should get the course for the lowest price possible so about ten dollars and uh then you get learning with Kafka and hopefully you like me and my voice and the way I teach and you buy them all. Nice do it do it this guy's good at what he does.

SPEAKER_01 40:39

Do it hopefully all right well my guest today has been Stefan Merrick Stefan thanks for being a part of streaming audio.

SPEAKER_00 40:46

Yeah I'm so glad to have been part of this thank you so much Tim for having me on the show and uh yeah stay cool and I'll see you soon.

SPEAKER_01 40:53

Hey you know what you get for listening to the end a Kafka Summit discount code. Kafka Summit is coming up on September 30th and October 1st in downtown San Francisco and you can get 30% off if you go to Kafka-summit.org and use the discount code AUDIO19 during checkout. Just enter Audio19 while registering at Kafka-summit.org and that 30% off is all yours. I'd love to see you there. But hey I hope this podcast was helpful to you. If you want to discuss it or ask a question you can always reach out to me at TLBergland on Twitter. That's T-L-B-E-R-G-L-U-N-D or you can leave a comment on a YouTube video or reach out in our community Slack. There's a Slack signup link in the show notes if you want to register there. And while you're at it please subscribe to our YouTube channel and to this podcast wherever fine podcasts are sold. And if you subscribe through iTunes be sure to leave us a review there. That helps other people discover the podcast which is a good thing. Thanks for your support and we'll see you next time