Bol.com - Techlab

There are two pillars in this episode. We start with the Technical Platform at bol.com. We'll explore what type of software engineering these teams are working on and what they are trying to achieve for the rest of our engineering community. The other part is Product Discovery. We try to figure out what problems we are solving in the discovery phase. While doing this we keep our focus on the Technical Platform and try to uncover how these specific challenges are solved.What this episode coversThe Technical Platform:What are we trying to achieve by having Technical Platform teams?Which product are they working on?How differs their setup from product teams?Are there other things that are different?Product Discovery:What – in general – are we trying to achieve during Product Discovery?Which problems are we solving?What roles should be involved to do this well?How to document those?What are the questions we ask ourselves during this phase?How to keep a good pace? The “customers” are facing a problem now and also expect an instant solution.Is this different for Platform Products?What aspects need additional attention?How well do engineers in the Platform Space know the challenges engineers in product teams are facing?How to get a common understanding of their problems?We wanted to stay away from discovery techniques as Double Diamond, Triple Diamond, Opportunity Solution Tree, Hypothesis Prioritization Canvas. Let us know if you want a specific episode on these techniques.GuestsTaco Bakker – Head of Product in our Technical PlatformOnno Ceelen – Group Product Manager Engineering ProductivityYou might recall him from his appearance in the episode on engineering productivity roughly 2 years ago.NotesThe Axle framework is one of the products our platform teams work on.We use Backstage as our Developer PortalThe Axle framework is one of the products our platform teams work on.

Moving Elastic Search to the Cloud. Elastic is one of the core components of the eCommerce Tech Platform. It powers the search engine as well as other trivial functions. In our own data center it has the biggest footprint. Time to discuss how the team approached this cloud journey. What this episode coversIn this episode we want to answer these questions:How do I transfer my Elastic Search data?What is Elastic Search migration?How do I set up Elastic Search on Google Cloud?Does Google Cloud have Elastic Search?Is Elastic Search cloud free?How do I change my Elastic Search storage location?How do I upload data to the elastic cloud?How do I back up my Elastic Search data?GuestsEgbert van der Wal ; Software Engineer in the Buying DomainRasjaad Basarat ; Software Engineer in the Buying DomainNotesOur Episode on building an FTP server on Rust is mentioned by one of our listeners Colin McAllister in reaction to a post about What are the advantages and disadvantages of using C for FTP server development?

If you look at the title of this episode, you might think that we are going to unveil our details about how we protect the bol.com platform against DDoS attacks. We should be clear about this, we just can't in the current world we live in. But we wanted to talk about this because the solution used is worthwhile sharing. So we double-checked with our security department and verified what aspects we can share; they are interesting enough.What this episode coversDDOS protectionFor an ecommerce site like bol.com, is this a large problem?With DDOS protection in place, what did we still miss? What needed to be improved?Could you give an overview of the solution you came up with?What sets it apart from solutions that are available in the market?Let's look at the data science partHow do we train the model?Is there a way to validate the model besides just using it in production?How do we deploy the model?Or how do we get the configuration for the servers from the model?How do cloud and DC (data centre) servers work together?How do we leverage for example the scalability of the cloud?Cloud load balancerCloud armourLooking back what did we learn about Cloud that can be used in other innovations?What did we learn about Data Science that can be used in other innovations?GuestsBarrie Kersbergen – Principal Research Scientist – Data Scientist RecommendationsWas on the episode on the Artificial Research Lab ~RecommendationsFrank Kootte – Product Tech Lead in Shopping/BuyingNotesPythorgAI Platform (Please check)

Chantal is on a mission. To make people aware of the buying drip or in Dutch "Koopinfuus". Together with Chantal we dive into this phenomenon and discuss what it is. We find out what the three pillars are that contribute to this drip. We make the connection with Tech. Tech empowers platforms like bol.com to use for the good and bad. Never before it was so important to be aware of this phenomenon and ask ourselves the question how we contribute to this. And just like her first book, it backed by a lot of research. The book will be released on the 17th of May and can be pre-ordered. What this episode coversWe dive into the buying drip (koopinfuus) by asking ourselves the questions:What is the buying drip? (Koopinfuus)Is there something in the tech culture in general that's amplifying this?What are the three pillars:Marketing TacticsBrain manipulationHyper personalizationHow this is used for the good and badGuestsChantal Schinkels - Social tech & e-commerce | Auteur "Het Koopinfuus" & “De IT Girl" | Professioneel Spreker | Columnist | LinkedIn Top VoiceNotes7 principles of persuasion Robert Cialdiniinfluence is your superpowerDark patternsEarlier Episode/Blog posts:Women in Tech Women in tech encourage inclusion in tech

The Tech Radar is a tool to inspire and support Engineering teams at Bol.com to pick the best technologies for new projects; it provides a platform to share knowledge and experience in technologies, to reflect on technology decisions and continuously evolve our technology landscape. Based on the pioneering work of ThoughtWorks, our Tech Radar sets out the changes in technologies that are interesting in software development — changes that we think our engineering teams should pay attention to and use in their projects.What this episode coversWe will answer questions like:What is a tech radar?What are we trying to achieve?What were the hurdles to get this technology radar?How do we maintain the techradar?GuestsRogier Lommers – a regular on this podcast – Space Tech Lead in our Tech Enabling spaceAnthony Moendir – Discipline & Community Leader of the Tech LeadsRemco Overdijk – Has also been on our podcast before – Product Tech Lead for our Compute & Networking Infrastructure within the Shared Technical PlatformNoteshttps://www.thoughtworks.com/radar

Neurodiversity is the idea that neurological differences, such as autism, ADHD, Tourette syndrome and dyslexia, should be recognized and respected as a natural form of human diversity, similar to cultural and ethnic diversity. The neurodiversity movement advocates for the rights and equality of individuals with neurological differences and promotes the idea that these differences should be celebrated and not stigmatized. What this episode coversWe structured this episode about neurodiversity into a couple of main topics:Introduction of the topic of neurodiversity and providing some background information about what it is and why it is important.Share personal perspectives on neurodiversity; two very personal stories from the guests of our show.Key Issues, Actionable Advice, conclusions and Call to action.The famous closing round; what are the key takeaways from our guests?GuestsKoen Suijkerland – Systems engineer for our TPS (Technical Platform Space).Krissie Prusinskaite – Software engineer in Logistics.Notes(Image: https://cdn.sanity.io/images/qxrxmo3r/techlab-prd/66a43f26137fbbb9c23c31cde7e15acd3dafe715-1045x255.png)In this episode, we refer to the episode about the Inclusion of introverts In the Netherlands you can also check out Neurodivergence and Mental Health in IT on Meetup One of our listeners pointed out to a closed channel on Slack as well. Let us know if you want to know more.

The guest of our show presented the Data Build Tool, DBT, in one of our knowledge-sharing sessions. Especially the fun part is what I recognize when I look at this knowledge-sharing session. The guest of the show presented it in an enthusiastic way and used terms like: the macro functionality makes DBT awesome and Ephemeral is the Unique Selling Point. What this episode coversIn GeneralWhat is a Data Build Tool?What problems does it solve?What are the two versions? Cloud, CLIWhy is it much more interesting to use than other ETL, transformation tools?Analytics EngineeringExplain a bit more in debt the Basics of a DBT project: dbt project data pipeline, data model, tests, macros.Model dependenciesDBT-packages ecosystemOne of the powers of DBT is Jinja.What could you compare Jinja to?Is it easy to comprehend and learn?Ephemeral (CTE) was the unique selling point for you, why?An engineer enthusiastic about a documentation feature… that asks for an explanation.Within bol.comUsage started as an experiment, how are we using it in bol.com?Can you share some learnings you and your team had when you started using DBT?GuestsSander Boumeester – Software Engineer in the experimentation team.NotesOn the website of getdbt there's a cool picture that explains the framework really well.

Five years ago, Chantal found out she got a lower salary than a male colleague with less experience. Till that moment she was ok with the male-dominated Tech world. But this triggered her. She started reading about this topic, interviewed many people and decided to write this book. She became very passionate about this important topic which you can already feel when reading the book. And while interviewing her, Peter Paul and Peter were triggered many times by this passion. What this episode coversThe BookThe book is an excellent combination of research, examples, tip&tricks and even a dedicated chapter for men.It's structured in three main parts:I: Voordat je het ziet - before you see it; there is a lot of information about why the situation is like it. It is going back to the past and explains why it is such an important topic.II: De ladder op – climbing the stairs; A lot of different work situations explained covered with tips to deal with this in a way close to yourself.III: Breek het system – breaking the system; last but not least the way forward to make a huge step. A dedicated chapter for men, a manifesto for more women in Tech and ideas to deal with the broader picture in and outside the company.GuestsChantal Schinkels – Author of “de IT Girl”Years of experience in the world of Tech. Supports companies in e-commerce ventures. Speaker at tech events. Trainer. AuthorNotesCynthia Nixon - Be a lady they said (short film)Women and inclusion in Tech

Order Sourcing Simulation is needed to enable capacity steering over our warehouses, network of sellers and logistical partners. Data Science is used to predict customer behavior and simulate capacity impact. What this episode coversWhat is:Order SourcingCapacity Steering (multiple warehouses, locations, etc)What is needed to do this well?IntakeEtc.Now the context is clear, we can dive into the issueWhat do we need to solve/achieve?And when the why is clear, we can dive into the Data Science part:When did Data Science popped up?How do you use this for this issue?What challenges do you need to deal with?BusinessTechGuestsBart Terpstra – Data Scientist LogisticsTimo van Hooijdonk Business Analist en Product OwnerNotesWe refer to earlier episodes on the use of Data Science in our logistical area and for forecasting:Digital Twin of our WarehousePredict the unpredictable

What is a product-led organization? If you google it you will find a definition in the 1.4 billion answers similar to this: Product-led means being guided by the potential of products and product teams, and breaking down the silos between “the business” and “the product”. The business IS the product. At bol.com, we are on our own journey to discover what product-led means. And we see similarities with the other journeys like becoming Agile, implementing DevOps, move to the cloud we went through. Only when we start to ask our Engineers what they need it really starts to flyWhat this episode coversFrom your perspective what is a product-led organization?Organization and roles.How work comes to the team of how the teams find work.Questions that are asked of engineers.How people in teams collaborate.How is it different for a software engineer compared to our Agile way of working?Design and preparationImplementingExperimentingBringing to productionHow did you get your first experience with this way of working?Does it require new skills and habits from our engineers?Or a more or less completely new mindset?Was there something you struggled withTaught you something newLed to new insightsIf there were one blog post, book, or video that engineers should consume, which one would it be?GuestsWerner Hofstra, Product Tech Lead in Assortment & SellingNotesEmpowered by Marty CaganContinuous Discovery Habits by Teresa TorresExperimentationInnovation RhythmProduct ArchitectureProduct-led by Tech Lead and Architect

Many know the retrospective from the agile way of working. It's one of the most important sessions in working agile. If done correctly and followed up it will make you better step by step. This is also the reason many people use it as instrument to improve after for instance an emergency. But what if retro's become boring? Some might recognize this so time to dive into this and make retro's great again.What this episode coversThe topics of the episode are:What were the symptoms of these boring retrospectives for you?Why are these bad for our teams? And our people?Could you share with our audience why this topic was important to you?Why do we need good retrospectives?What are the elements of a good retrospective?What were the alternatives or additional styles and structures you came up with?Could you share some insights on the struggles you had and what you learned from them?GuestsErik van der Kieft - scrum master in Assortment & SellingJake de Oude - Software engineer and scrum master in Assortment &SellingNotesThe Spotify Retro Kit

With 2 of our engineers, we look into how we keep enhancing the quality of our webshop using canary testing and analysis, contract testing and end-to-end testing in isolation.What this episode coversWe have quite some communities within bol.com. One of those focuses on quality. For this episode, we invited 2 engineers from this community to share some of our latest developments on this topic. They share their knowledge and experience with canary testing and analysis, contract testing and end-to-end testing in isolation.We go over questions like:What is canary used for?What is a canary deployment?When should end to end testing be done?What is End 2 End test?How do you perform end to end testing?What is the purpose of doing end to end testing?GuestsSonja Nesic; Test Engineer in the buying domainRonald Nikkels; Test engineers in the buying domainNotesRonald shared a link to a meetup/youtube video: Pactflow and Cypress (End-to-end Tests in Isolation using API contracts with Cypress and Pactflow). Sonja shared an article in the quality community about Deployment Validation and Graceful Degradation at Pinterest.

In the introduction mail, it said: “Having a culture in which we all can thrive, is one of our most valuable assets. To celebrate and cherish our unique tech culture, we are organizing events throughout the month of June. ” From Meetups to Games, from Tech talks to sessions with the IT management and most important of all, interactions. That's in brief Tech Culture Month. We hope to inspire you to have one yourself or participate in these tech community-building events. What this episode coversWe discuss Tech Culture Month.What is Tech Culture Month?Why is a series of events like this important?What was the feedback from the community?During this month our Tech Culture Manifesto got introduced.What is it?You Build It, You Run It, You Love It!Have FunWhy do we have or need this manifesto?What did we learn putting this on paper?GuestsBabiche de Jong – Software Engineer in LogisticsJonna Hietkamp – Principal Engineering Manager in Assortment & SellingTim van Hardeveld – Coordinator Onboarding, Learning & DevelopmentNotes

This experiment triggered so many questions with us: Creating a pop up warehouse with Google Glass implementation, how much time does it cost? Why are we doing this? Is this totally new in the market? What this episode coversWe dive into the experiment with this business usage of the Google Glass in a popup warehouse. (Image: https://cdn.sanity.io/images/qxrxmo3r/techlab-prd/1ee7d3b5ecc11dc4ba0e0f381665fc820b5ee8b2-4032x3024.jpg)GuestsTuran Bulmus – AI/ML Practise Lead at Google for the BeneluxNiels de Vries – Data Scientist at bol.com within Logistics – stock allocationMelih Gultekin – Software engineer/Android developer at bol.com – decide to buyNotesGoogle glass, Own OS (oreo, android)Figma – design - https://www.figma.comGoogle cloud visualizer on laptop - https://www.vysor.io/Jackpack compose (google library for android dev.s, Kotlin)https://developer.android.com/jetpack/compose/documentation Customer cases: Samsung, DHL and outside logistics: Health SectorGoogle guidelines for color schemas

Over three years ago we published our third podcast episode. The topic of the episode was the Go programming language. We noted, “When you listen to the stories our two enthusiastic guests share in this episode, you might even believe Go is the future.” So, let's check in and see how things have evolved. The number of feature teams in bol.com using Go has grown. What else has happened? Our guests share their experiences and provide solid advice for starting your journey with Go.What this episode coversIntroducing the Go programming language in an organisationWhat do we like about Golang?How to onboard people in the Go experience?What is a good approach to deal with boilerpate code in Go?Should you generate it? Or use a "framework"?What frameworks are available?GuestsPatrick Akil – Consultant, Software Engineer, Trainer in Go, Podcast HostAlbert Brand – Consultant at Xebia – Software Engineer, Go TrainerGoos van den Bekerom – Software EngineerHannes de Jager – Software EngineerKevin van den Broek – Software EngineerNotesOur 1st podcast episode on GolangThe power of GoAxleThe Functional toolkit for Kotlin HTTP applications - http4kCookie cutterGo kit

We discuss the way of working of the Tech Lead and Architect in the Marketing Domain. Functional- and Technical aspects need to be taken into account when defining the direction of the development teams. From our guests Alexandra and Lennart, we learn what cooperation means in these relatively new functions. What this episode coversProduct-Led is adapted more and more as a way of organizing for innovation. In bol.com we are shifting towards this concept. One important topic in the adaptation is forming the leadership in a product organisation. Given the nature of the innovation teams we both need to focussing on functional- and technical aspects. GuestsAlexandra Egher ; Product Tech Lead in the marketing domainLennart Billekens;Product Architect in the marketing domainNotesLearn more on the introduction of Tech Leads at bol.com.Product architecture for the product organization.Check how we adapted out innovation rhythm when introducing a product led approach.

A few months ago we noticed a message that stood out on our internal platform. Basically, it stated: "I'm back". Naturally, it happens every now and then that employees explore their horizons but still return to bol.com.What this episode coversHowever, the number of software engineers that turn to indie game developer and come back, is quite limited. That sparked our curiosity since for a vast group of engineers it is some kind of dream job to develop games. That must have something to do with the large number of gamers among software engineers.There are some interesting learnings and experiences in our conversation with Roy. Listen and check what is in it for you.Have you always been intrigued by creating (computer) games?How did you prepare for your adventure to make games for a living?What were the obstacles you had to overcome trying to make a living crafting a computer game?What did you learn?Please share also some examples of how you learned this?What will you take with you now that you are back at bol.com?How is it to be back at bol.com?GuestsRoy Kok – Software engineer at bol.com in Buying and former Indie game developer.NotesUnity

Everybody can go to bol.com and check the Front-End of our webshop. But what if you are a seller, supplier, partner or internal employee? What is your view when interacting with our IT systems? In general, you will use one of our Portals. These portals made a long journey to get to the stage where they are today.What this episode coversNot only does the backend site, mainly covered by SWAP's (Small Web APplications) rely on different frameworks, also the Front-End work does. How to adapt to a new 'Look and Feel'? How to be consistent? How to make the lives of Software Engineers easier? Listen to this episode and find out yourself.What does the Portal and SWAP architecture look like in bol.com?What is a front-end framework?What role play Design Systems like Figma, Storybook, Zeroheight, Frontify, Stencil?What are design tokens?How do UX Designers, Front-End Developers and Back End Developers work together and profit from a framework?GuestsJake de Oude - Front-End Software EngineerRobin Aldenhoven - Software Engineer within Logistics working on Front-End applicationsRobin Cijvat – Product Tech LeadRens Jansen – Visual designer design system designer – new bol.com style in the component librariesNotesIn an earlier episode back in 2019 we already talked about SWAPs and a blog on this topic is available here.

Welcome to episode number 100! A special show with a very interesting topic: Inclusion of Introverts and Introversion. We asked our CEO Margaret Versteden for a quote for this number 100. She surprised us with the fact that this topic is so important for her as she is dealing with this her whole life, as an introvert. So if you are an extrovert, we think this is a "must listen".What this episode coversIt will help you to understand and to make the world and your environment safer for introverts. It is about the inclusion of everyone and the inclusion of introvertsWhy is it so much harder for an introvert to be included than for an extrovert? To understand this, we first dive into questions like:What is an introvert?And what it is not, what are the common misunderstandings?Why is it so important to be more aware of these differences?We touch upon neurodiversity and neuro non-typical persons, as some of the requirements for a safe environment also applies for these groups.After this understanding we dive into the environment:What creates a safe environment? How to include diverse people?What can you do as a facilitator?We talk about meetings, presentations, standups, dealing with feedback, spark meetings and many more examplesWe discuss tips and tricks to build a more inclusive environmentAnd we are confronted with our own bias, more than once.GuestsJoão Martinelli - Software Engineer and Scrummaster in one of the Payment TeamsSarah Gruneisen - Engineering Manager, Agile Coach and LiberatorReena Choudhary - Software Engineer in one of the Payment TeamsNotesLiberating Structures: https://www.liberatingstructures.com/Other shows on Diversity and Inclusion:Cultural Diversity

We are not only the hosts of the show but so far we also do the selection of the topics ourselves. Research what's interesting. Find diverse subjects and guests, etc.What this episode coversAnd sometimes guests make it easier for us. They post on our internal platform a message….“What is the superlative of bragging? I don't think I can go any further than telling you that I co-wrote a book. And of course, it's about experimentation Yesterday I received the first copy in my hands, and it is of course for sale at bol.com ”The book is called “Steering on results”, how to work together on the greatest ambitions. Work smarter not harder. (So far only available in Dutch but English translation is being worked on). And since this week we know that the book is on the long list of books to become Management book of the year in 2022. A Dutch award organized by one of our partners managementboek.nl. (how can I check if this is true?)This triggered us in two ways:First – what is the book about?Learning by three elementsDataTangible ObjectivesIntroduction of CRAFT: Create, Refine, Align, Finalize & Transmit (CRAFT)Introduction of Objectives, Progress Metrics & Estimates (OPME's), in bol.com we refer to this one as OKR's.3. thorough research methodsSecond – How is it to start writing a book?So we know how it started, let's find out what it is to become an author next to your jobWhen did it start?Why did you choose to do it?How did you work together?What steps did you take?Did you already have experience in writing?Was it according to expectations?What were the learnings?Do you advise others to write a book?GuestsWe have an award-winning guest:Denise Visser; According to Linked in it says Product Manager Experimentation at bol.com and freelancer.You probably know Denise from a previous show about experimentation.NotesSturen op resultaat websiteThe Book Sturen op ResultaatBlog on experimentationPodcast Episode on experimentation with Denise and MaartenLonglist management boek van het jaar

This episode is 2021 Techlab Wrapped. Inspired by one of the platforms that host our podcast Spotify. It is the end of Season 3 and the end of 2021. Time to look back and to look ahead.What this episode covers2021 Wrapped and maybe a glimpse into 2022.We look back at 2021 by the numbers.Top 3 listsTop 5 countriesWe discuss the topics and episodes that really got us.For instance the one on Log4j and the PMC member who is working in bol.com.We share the plans of 2022 and the OKR we set ourselves: "we get on TikTok and you get to decide what dance we should perform if we double our listeners on the best episode ever"GuestsPeter BrouwersPeter Paul van de BeekShownotesTop 3 according to BlubrryEpisode 91 - Retailer APIEpisode 93 - The Programmers BrainEpisode 81 - Data Maturity and Data LiteracyTop 3 according to SpotifyTeam TopologiesThe Data-Driven Approach to supporting products with KPI's and OKR'sCuriosity is the common denominator for our business analystsThe new Bol.com ECOmerce podcast about sustainabilityNotes

During the recording of this episode, we are in the week of Black Friday. An exciting week for people hunting for bargains. And also for a lot of our colleagues.What this episode coversWhether that is from a commercial point of view or an engineering one.All the eyeballs on our website, bring a lot of traffic. And consequential a lot of load on our systems. In this episode, we focus on one aspect of preparing for a large load: Load Testing. In this episode, we are going to talk about Load Testing with Locust. An open-source load testing tool.Triggered by our guest's presentation during the spaces summit, we wanted to know more about this and share it with you.What is Locust?Why did we start using Locust for Load Testing?Examples of Load tests and Performance tests performed with this toolWhat did we need to setup for it?How to configure your Locust testsHow to run your tests on KubernetesWhat were the challenges?How does it make use of the cloud benefits like scalability?GuestsLeon van Wijk; Full Stack Software Engineer at Craftsmen and engineer in our Logistics TeamNotesDistributed load testing with LocustLocust presentation at the Spaces SummitPerformance testing the Chat App

If you are a regular listener to the podcast or an e-commerce watcher, you know “the season” is very important for us. It is a yearly recurring theme in the podcast. You are probably also aware that uptime and responsiveness of our app and website are crucial.What this episode coversAnd you might have noticed that enabling our software engineers to perform at their peak is very important for us. Enabling teams and engineers is what we do to build a great place to engineer.And sometimes things just go sour. A perfect storm occurs that is definitely not a tailwind…As our CTO will say “never waste a good crisis”. We have to learn from what happened. Let's explore one of those incidents. We go back to the season start of 2019. Just before the start of the Friday Afternoon Drinks, a huge incident started in our Android App. This triggered downtime in other areas of the platforma as well. And maybe just like when investigating a plane crash there is not just one thing that was off but a series of unlikely things happened in a short span of time. Let's dive into this.Why is learning from failures an important topic to share?Some context, what part of the landscape are we talking about in the episode?What was your perspective? What were you doing and what happened?Taking a few steps back: What was the process of incident management and how did we step by step fix the issue?When the dust settled: What did we learn? What did we improve?GuestsJulius van Dis – Full-Stack engineer at Flock. He was responsible for the app, specifically its direct backend. Some of the projects he has done include making the app and service landscape multilingual, the migration and integration of a new gateway, creation of a basket API and improved app updates.NotesJulius adventures at bol.comMobile App updatesMoving to multilingualPodcast on multilingualRefactoring the mobile app APILearnings and next steps

In this episode, we virtually visit the AI for Retail Lab and dive with two members into the world of recommendations. The AI for Retail (AIR) Lab Amsterdam is a joint UvA-Ahold Delhaize industry lab and conducts research into socially responsible algorithms aimed at the retail domain. Think of developing models for recommendations and managing goods flows.What this episode coversThe research, testing and application of the models take place in Albert Hein Delhaize and bol.com.What is the AIRLab (Artificial Intelligence Research Lab) and what is it trying to achieve?PHD projects?How does science profit from business involvement and the other way around?We take a deep dive into recommendationsWhat is being researched?Why is this important?What is the hypothesis?What has been discovered so far?Explore the approach to the research.How can both business and academia benefit from this research?GuestsBarrie Kersbergen – Recommendations bol.com & PhD Candidate at AI for Retail LABSebastian Schelter - Assistant Professor at the University of AmsterdamNotesAIRLab research papersEarlier episode on the gathering of measuring data. The feedback loop for recommendations

Warehouse mechanization is a part of our IT landscape where our IT meets the physical world. It is one of those places where we encounter that while we could scale our IT almost indefinitely in the cloud, the physical world and warehouses don't work that way. As you listen to this episode you will learn how the world of IT has to adapt to the physical world to make things work. And as Peter states this is also the place where e-commerce comes to life.What this episode coversThis is the place where all the bits and bytes in the webshop have to lead to tangible products that are picked and delivered to our customers. By all measures a real interesting place.:What sets warehouse mechanization apart from other software engineering?To enable our growth we need more and more warehouses. What do we need to get a warehouse live from a WMS and/or warehouse mechanization perspective?To what extent do you need access to the physical parts?Do we use simulation?GuestsFrank Lakerveld – WMS consultant in LogisticsDennis van Duijn - Systems Engineer in LogisticsNotesSimulation and Data Science for our warehousesPerformance boost the picking algorithmThe life of a WMS consultant

Some aspects of software engineering are easily overlooked. In the book The Programmer's Brain some of these like reading code, thinking about code and collaborating on code are at the centre. In this episode, we talk to the author of this book to guide us through these aspects. To improve your coding skills it is good to know how your brain works.What this episode coversThat will enable you to set your brain to work for you. If you spent significantly more time on reading code than on writing code, shouldn't we focus more on learning to read code? These are the topics we explore in this episode.If you've ever wondered what working smarter instead of harder is supposed to look like, you should read this book. I am already seeing improvements in my day-to-day work.What the programmer's brain coversWhat every programmer needs to know on how the brain works.What you should know about cognition.A lot of exercises for programmers.How do I improve myself on coding?What is the difference between an expert and an intermediate programmer?And Felienne shares ideas and working formats to improve collaboration on programming.GuestsFelienne Hermans - Associate Professor at LIACS - Universiteit Leiden. Keynote speaker, podcast host and book author.NotesThe book on bol.com: https://www.bol.com/nl/nl/p/the-programmer-s-brain/9300000033887759Code Reading Clubs: https://code-reading.org/More on Engineering Productivity.

Imagine you want to buy something. You go to bol.com and you start typing the article in the search bar. Automatically you will be served suggestions and as a result, you want a limited number of articles from our 30 million products catalogue.What this episode coversYou select the product you want, press the buy button and there it is, at your doorstep at the selected moment.Sounds simple, right?Inspired by a talk of our guest of this episode earlier this year, we wanted to find out what's behind the search bar. We wanted to understand search queries. Simple at first glance, but when we dive into it we found out it's way more complex than you might think.We had great learning: as a customer, I help other customers to improve their search results. How that works? Listen to this episode.(Image: https://cdn.sanity.io/images/qxrxmo3r/techlab-prd/bd51783981f1b35051359902ea03bea2213d1a9f-680x361.jpg)The search bar on the bol.com websiteWhat it takes to searchQuestions will be answered like:How do I search for a product?We are not talking about the Google Search Engine and SEO and why we do not use Google Search?How important is search?What happens when you type in a search query?Terms you need to understand when we talk about search: relevancy, ranking/sorting, first page, tail page.What items do you need to take into account: Spelling, Target Category, Filter values, Broadness.How do we take trending topics into account?As an International Engineer, is it hard to work on a search engine with Dutch Product Content?GuestsNikolai Bogdanov – Software Engineer in the Buying domain – Help me find.NotesSpaces summit Talk on YoutubeThe search result of the red water kettle as given in the exampleSearch via Voice is different, check this episode for more detail

In early April the latest version of our Retailer API was launched. Given the importance of the API for almost 15.000 partners this was again a major step. Over the years the retailer API became the heart and soul of our ecosystem.What this episode coversBut this path wasn't always that obvious. It took vision, decisiveness and perseverance to get this far. In this episode, we explore this journey.The importance of the Retailer APIAPI's are considered a major part of a serious platform. They enable growth and stability. The 80/20 rule applies when it comes to the usage of the partners of their interaction with bol.com. 80 per cent of the sellers use the seller dashboard, 20 per cent the Retailer API. But when it comes to the number of orders, it's the other way around. 80 per cent via the API and 20 per cent via the dashboard. And if you imagine that over 50% of the goods being bought at bol.com are goods from our partners, it shows the importance of this API.What we discussed about the Retailer API (Application Programming Interface)What is an API in simple terms?Why is API used?How did we start the API?What functionality is in the API?What is API and types of API?What is API to API integration?What is API example?How does the API interact in the Landscape?How do we balance "adding new functionality" vs. "maintenance"Why became the Retailer API the heart and soul of the ecosystem?GuestsMaarten Roosendaal – Business Architect / Product Owner for our Retailer API;Jarno Walgemoed - Owner at Sourcelabs; Software engineer with a strong focus on partner API's at bol.com and host of the sourcelabs podcastNotesIn an earlier episode, we talked about API development for bol.com and we also touched upon the Open API. The API is used for customer interactions. https://techlab.bol.com/api-development-for-the-retail-platform/API Developers can find more information here: https://developers.bol.com/

Engineering Productivity With the growth of our engineering community, the need for more focus on engineering productivity is clear. We invited two experts to discuss this topic with us. We actually got to this point when one of our listeners pointed out one of the products we are using for this and how awesome a topic that would be for our podcast. Backstage The product he was referring to, is Backstage.What this episode coversBackstage is a platform for developer portals that is used as an app store for tools for software engineers. This product was build inside Spotify and later on open-sourced by them.We thought it was a good idea to get these tools in a unified packageQuestions we touch uponWhat does engineering productivity mean?How is engineering productivity measured?Why is engineering productivity important?How can engineering productivity be improved?What is Backstage open source?Who uses backstage io?Why Backstage io?What is Spotify backstage?GuestsRoy Jacobs – Software Engineer – Technical Platform. Already joined us when we explored Axle – the opinionated support for our scrum teams using JavaOnno Ceelen – Product Manager – Technical PlatformNotesBackstage homepageIntroduction to Backstage at SpotifyAxle the bol.com Springboot framework: podcast, blog on Axle usage

How interaction resulted in a guest appearance “We like interactions and feedback”, that's what we say in our outro. The guest of our show reacted to one of our podcasts earlier this year. We reached out to him and invited him to the podcast.What this episode coversWhy? Because it's good to look in the mirror. Check our stories with the outside in view. And that's exactly what we are going to do in this show. Getting the outside perspective on the edges of autonomy.Discussed Items on the edges of autonomyWhy do you interact and why is interaction helpful?How can we complete our stories?What items do you miss when you listen to the stories in a holistic way?What is an example of autonomy?What is team autonomy?What is autonomy and why is it important?Does autonomy mean control?What are the three types of autonomy?Is autonomy good or bad?GuestsThomas Heijtink - Full Stack Software Engineer & Product Owner at Fleetgo, but above all loyal supporter of the show and searching the interaction.NotesAgile at scaleMan on the moon

How Data Science supports us to predict the unpredictable Just like for any store, forecasting is an important tool to support the business and its profitability. At bol.com we have worked on several major iterations of our forecast. One of the hosts worked on a large leap in forecast performance over 8 years ago. You can check some another leap we have made while listening to our podcast episode from May 2019 - nom more crystal ball for forecasting, Data Science it is. In this episode, we explore how we have improved on that one.What this episode coversOne of the leaps we made Is in the operational part of running a Data Science-based forecast in production. This is intriguing because this mechanism at the same time speeds up our innovation speeds because it enables us to do more experiments and train our models more often.One important input we added to our forecast during the pandemic was the "Covid Severity Index". This improved our forecast performance and enabled us to work with scenarios. The latter also supports all the other retailers that sell on our platform.Discussed Items on forecasting with Data Science in Covid-19 TimesForecasting in generalSpecific forecasts for specific needsAggregationCoherenceWho is responsible for what?What can we predict with Data Science?How do you forecast sales Data Science?Tech usedInput dataExperiment by using branches to innovate fasterAirflowDr. Watson as a gatekeeping tool to validate the outputCorona impact on forecastingCovid SeverityGuestsCatia Silva – Data Scientist in forecasting. Presenting at conferencesEryk Lewinson – Data Scientist in ForecastingNotes

Why build an open-source FTP server in Rust? Sometimes, I must admit I'm a little dazzled by all the languages, frameworks and stuff our engineers work with. So, when our guest of today explained to me some of the intriguing aspects of the language we will be discussing in this episode I had to stretch my mind a little. I managed and could follow his explanation.What this episode coversAnd I found a great topic for this podcast.In the episode, we explore the Rust programming language and our first open-source code in this language: unFTP. When you need to FTP but you don't want to. We will show you the advantages of using this FTP server in the Cloud for the cases that still require you to FTP.What we discussedThe programming language RustWhat is Rust and why is it so popular?What programs are written in Rust?Why should software engineers learn Rust?The project unFTPWhy unFTP?Where does the need for a cloud FTP server stem from?unFTP as Open Source projectWe open sourced unFTP. What are we trying to achieve by doing this?What are the results so far?Did it help that unFTP featured on This week in Rust?GuestsHannes de Jager – Software engineer for the retailer bol.comRob Klein Gunnewiek - we called him System Engineer Extraordinaire last time he was on the show. Besides that, he is one of our Site Reliability guru's.NotesTurning rusty tech into Rust ~ When you need to FTP but don't want tounFTP Github'libunftp on crates.ioThis week in Rust on unFTPThe Terraform wrapper that was mentioned

Who is the Podcast .Guests?This will be a bonus episode. Maybe not that tech-related but instead you will listen to a very energetic, passionate and inspiring person: The PodcastNotes

What is the key competence of our business analysts (BA) We talked about domain knowledge, tech affinity and building bridges between stakeholders and software engineers. Sometimes the business analyst is almost seen as a project manager. Aligning with product owners is key in this role.What this episode coversEvery business analysts within bol.com fills in this role differently but about one thing they are very clear; for our business analysts curiosity is key.Time to dive into this BA role. We see this role as a key to success in our multidisciplinary product teams. They form a bridge between the stakeholders with their business requirements and the software engineers providing the tech solutions.GuestsAdinda Biesbroeck – BA Retailer portal – 5 years at bol.com.Naomi Platenburg – BA Capacity Management Warehousing – Daily steering – started in March after an internship.Mitch de Vries – BA Team 15 C – Contract en Condition management in Retailer1 - 3 years at bol.com.Notes

Next level leveraging cloud computing We moved 70% of our services to the cloud and new services start in the cloud unless... Time to dive into a topic brought up by our tech leads. Want to know how you can maximize your cloud benefits? Alexandra wrote a blog post on Horizontal Pod Auto-scaling, HPA.What this episode coversIt triggered us for this episode.Maximizing cloud benefits can be done in many different ways. For this episode, we dive into auto-scaling. Cloud computing brings great features for scaling up and down based on the needs of an application. But if you think my application can scale on-premise, just copy that principle in the cloud. Think again. You might be overspending or still underperforming. Our guests explain why this is and what to do to maximize your cloud benefits.Topics discussedIntroductionWhat our cloud strategy is (GCP, run in Kubenetes, Istio, cloud-native, etc)Migration strategies for feature teams (check)Lift and shiftMove and improveRip and replaceExplain horizontal vs vertical scaling (based on the lawnmower metaphor)A concrete example of using k8s HPA: MESS applicationPrerequisites before setting up HPABefore and after setup:The only way to make this faster is by adding bigger hardware and remain the number of instances.And IF you can add more instances easily, then there is the problem that the new instance contains everything, so you're not only scaling the parts where it hurts the most.Cost optimizationGuestsRogier Lommers – Space Tech Lead at bol.comAlexandra Egher - Product Tech Lead at bol.comand both friends of the show!NotesThe podcast about Axle, our own framework for developers based on Spring Boot can be found here R2D2, our own cloud integration tool is explained in this episodeLink to Techlab blog post of AlexandraSidenoteIn general, a story about architecture that relates to all of this.

Writing an article is reflection, publishing it is getting feedback Learning from our colleagues. That is important to us. So, we were delighted when we found another great piece of this on LinkedIn, Elinore shared. to inspire others who are thinking of transitioning from tech into a leadership role or are just curious about my experiences and thoughts. The transition from tech into a leadership role is actually a very hot topic and not only within bol.com.What this episode coversWe learn this from the job interviews when candidates ask us about career paths in bol.com. Also when we introduced the role of the tech lead in bol.com last year. And when we formalized the job profile for Engineering Manager. We used to call this Team Lead IT and with this formalization, we also had discussions about the background of the Engineering Manager should or shouldn't be a former engineer?In the article Elinor addresses 5 aspects she learned:Management Is actually a job.You can't have the cake and eat it too.A leader doesn't have to be a manager.What got you here won't get you there.Your next step is not the rest of your life.We will go over these items in this episode and along the way we touch on other great insights, will there be a next article? One of the insights we want to share with you here is that a lot of people in tech are leaders.GuestsElinor Bakker – Lead Architect, Creative problem solver and silo buster. Friend of the show, Small Web AppsNotes

From how it was born to what it is now in 45 minutes One of the things that make us really proud about working in Tech at bol.com is our annual Space Summit. Our internal tech conference by developers for developers. And maybe you can recall we had quite some interesting episodes, blogs and videos about it and some of the talks given there in the last 2 years. This year is a special edition! We celebrate our 5th anniversary!! In June 2018 Peter published an article on Linkedin with the subject: “What happened to me today? After the Spaces Summit of that year, he had to write down that experience.What this episode coversWhy? Because he was really proud of what the engineering community within bol.com was capable of. And now, three years later we celebrate the 5th one.Topics in this episodeThe journey of the spaces summitThe early years.GrowingMoving to an online eventAnniversary edition - hybridThe futureThe organization of the Spaces SummitPreparationCommunicationSpeaker selection and preparationSpeaker supportCoordinationFun stuff and EnjoyingMediocre stuffPlaygroundRaising the bar is what we do in our jobs but also for this summit.How do you top each year the previous year?GuestsLuc Kleeven – Software Engineer (Platform) – Venue and budgetAysegul Guldes – Software Engineer (Reverse) – Venue and budget + Speakers and programJasper Adegeest – Data Scientist (SAFe space) - Speakers and programTim van Hardeveld – Coordinator Onboarding, Learning & Development- Venue & Budget + Playground +Notes

Data Maturity Model as common ground, Data Literacy Model to measure the level of speaking, writing and reading data To state as a company we want to become more data-driven is the first step. To truly understand what this means and define a common ground to discuss the progress is the second. Back in the eighties, the Capability Maturity Model was defined to develop and refine software development processes. Later on, many more Maturity Models were introduced like the Business Maturity Model, the Lean Maturity Model and Agile Maturity Model.What this episode coversTo develop and refine the data-driven organization, we created the Data Maturity Model. This model enables us to measure where we stand in our goals towards 2023:Our data consumers are self-sufficient: They know what they need, what they look at, how to analyze this and how to use insights/focus on in their daily jobs.We want to do this in a scalable way and empower the users.To know what the current level of maturity is in the organization we apply different models and this helps us to fill in the white spots (e.g. in training).And we can apply the same for partners (future).Bol.com Data Maturity Model(Image: https://cdn.sanity.io/images/qxrxmo3r/techlab-prd/b5fe8f6cd4bdcc72dda891985ce7b2eea9cdd40f-680x382.jpg)Data Literacy ModelOne specific element of the Data Maturity Model is about skills. On what level are you able to read, write and speak data. This is captured in the Data Literacy Model. We discuss the bol.com interpretation of the Data Literacy Model.Bol.com Data Literacy Model(Image: https://cdn.sanity.io/images/qxrxmo3r/techlab-prd/6a8ecfb1da2940d4b945dd2da57e989d67dce4dc-680x286.jpg)GuestsWillem Bekkers – BI specialist and Data Coach – involved in eg our measurability month.Meike Teunissen – BI specialist who is in the Autonomous Insights team and the expert within bol.com in Tableau.NotesThis podcast episode can be seen in a combination of podcast episodes covering the data-driven organization:Data-Driven Approach to supporting products with KPI's and OKR'sInnovation Rhythm - How to drink less coffee and achieve moreCloud as Enabler to become more data-drivenAgile at Scale – Reality is complex, don't expect simple solutionsOKR Guide

Supporting products with KPI's and OKR's We had previous episodes on how bol.com is moving to a product organization. In this one, we'll dive into how to measure the success of these products and set objectives for them. Including measuring whether we are getting the desired results.What this episode coversBeing the data-driven company that we want to be we asked our data people to help us to get the right KPI's for all our product and support the products in defining proper OKR's.Data availability should never be an excuse to not start KPI's or OKR's - Frans PoldervaartWe came with a team to support products with KPI's and OKR's. One of the recurring themes is the difference between KPI's and Key Results and what their relation is to metrics. If you want to know more about that topic, check this video.What will we explore?Some context first. What are domains, products, OKR's and KPI's.What is a product KPI and a product OKR?What is the difference between OKRs and KPIs?What is the Product KPI and OKR program about?How do you set OKR's?How do we support our teams with this?6 elements of a data driven team.Data culture.What does this support look like?Data maturity model.What did we achieve?Data coaching toolbox.GuestsWillem Bekkers – BI specialist and Data Coach – involved in eg our measurability month.Frans Poldervaart – BI specialist and Data Coach, who thinks he is over-exposed and a big fan of the Hoi Anh food truck. Loves sharing all kinds of data thingies on bol.com.NotesThere will be an upcoming episode on data literacy framework.OKR GuideKPI = Key Performance IndicatorsOKR = Objective and Key Results

Every time I look at you. I see myself.I'm so proud of you.For you help make me what I am.A better man.I'm just so proud of you.~ Lyrics by Alain Clark A special episode comes with a special opening. In February we had an extraordinary occasion during our onboarding.What this episode coversFather and Son in the same 'virtual room. Father started as Software Engineer in the bol.com security department and son started as... Software Engineer in the security department, doing his final intern assignment.We have got many examples of father and son working relationships, One of the most famous at the moment are Max and Jos Verstappen. And we know more in the F1 (Hamilton in the past, Stroll). And of course, we know about company's set up by one and succeeded by the other. So, really interesting to find out how that works in IT.This story gave us a lot of hooks to discuss different aspects of our Engineering Culture and Way of Working. Besides the fact that we had a very proud father in the show, he also explained how he is impressed by the speed of this young generation. It will give insights into the internship position and the role of the intern. Is an intern an employee? What type of employee? At least we discuss what it means to onboard for an intern assignment and the steep learning curve to overcome in our environment.He will always be my child, but he is not a kid anymore - Chris PoldermanIt will trigger you to think about your own relationship with your kid and/or father/parents. Do you know what your fathers work look like? Your kid is ready to enter the working life, did you perform well as a parent? Is your father the same person at home as he is at his work? What can I learn from my own kid?GuestsChris Polderman – Software Engineer in security.Martijn Polderman – Intern in securityNotesFather and Friend - Alain Clark

The why and what of our Software engineers on Duty Let's be honest about this, nobody likes to be woken up at night to react to an alert whether it's a text- or whatsapp message, (automated) phone call or traditional pager. But every company taking his 24/7 run seriously has to organize their on call duty in a scalable and sustainable way. Initially bol.com organized it in a traditional way, meaning a team of system engineers with different specialism took care of the duty.What this episode coversOnly a couple of years ago we realized we needed Software Engineers in this setup as well. In this episode we ask our guests everything about this journey so you can learn from this.We explore aspects and explain why you sleep well at nightWhy did we start the Software Engineer on Duty (SoD) initiative?What does the current SoD look like?What is the relation between SRE and SoD at bol,com?What are the prerequisites for a team to hand over responsibilities to SoD?Experiences working as an Engineer on Duty.GuestsRuud Straver - Site Reliability Engineering ManagerBart Enkelaar - Regular on the podcast, host of the Friendly Tech ChatsNotes

Don't miss our story of the introduction of the Tech Leads During the podcast, you will find out what Tech Leads are and why we need to build this community of Tech Leads at bol.com. You will learn how we approached this and avoid hiding the Tech Leads in ivory towers. The two tech leads and an IT director share best practices and pitfalls (and what we learned from them). The Why and What of our Tech Lead Community Tech Lead Community Why did we start to define the role? What is the Tech Lead for bol.com, Responsibilities Product Tech Lead Space Tech Lead It's a fun challenge and it's taking time" - Eduardo da Silva The backlog of the tech leads Backlog of community Tech Radar Tech Vision Backlog Space Tech Leads Cloud Migration Backlog of products Examples Introduction of the role (process) Definition Scale, number of Tech Leads needed Rollout / Hiring part Building the Tech Lead Community Lessons Learned so far Best Practices Pitfalls / Challenges.GuestsAlexandra Egher; Product Tech Lead at bol.comMirko van Ede; Director IT - Shopping & Marketing Technology at bol.comEduardo da Silva; Tech Leader & Sociotechnical Architect at bol.comNotesThe book Talking with Tech Leads by Patrick Kua.We talked about API design and development in a previous episode.

Introduction Peter is very honest in this episode (the stage is not the place he is really comfortable at) and Peter Paul is sharing his first experience with Improv (is it a small trauma Peter Paul?). So time to talk about Improv, Improvisation Theatre and applied Improv because we do want to learn about it and we are really curious how this relates to our Tech Community. Our guest Burgert prepared this along with these main topics Mindset, Skills, Culture, Structures and Who benefits. Mindset - Relates to the Improv Manifesto Making your partner look good over making yourself look good. Saying yes and over saying yes but. Playing in the moment overthinking and talking about the past of the future. Everything is an offer. There are no mistakes. Be average. Make a strong choice and stick to it. Skills Listening. Making choices. Speaking with confidence. Connecting/collaborating with others. Mental agility. Staying calm in uncertainty. Role flexibility. Culture Safe to make "mistakes" - happy accidents. The positive atmosphere of acceptance. Open to what emerges. Respect and value for others. Courage. Commitment. Focus. Structures Games, formats. Who does benefit I - The Individual We - The Team Everybody - The Organization.GuestsRob de Groot; systems- and metrics engineer in the Technical Platform.Burgert Kirsten; Way of working coach in Platform - Innovation Support. He previously appeared in the Techlab post on human systems engineering.Notes-

Introduction In July 2019 we had our first podcast episode on voice and Google Assistant. Back then Marieke and Marvin introduced us to the future of interaction by voice. In this episode, we dive into the potential of brand recognition. Many people in The Netherlands will recognize the voice we use in our commercials on radio, television and social media as the voice of bol.com.What this episode coversThe value of this brand recognition is the starting point of the journey to get this voice into the Google Assistant. By doing so we differentiate from our competitors who are using the 'regular' Google Assistant voice.Join us to see how we can increase brand recognition with Google Assistant.GuestsKristiaan Hoogendoorn; system engineer in the Site Reliability Team and Young ProfessionalDave van Kasteren; software engineer in the Logistics domain and Young ProfessionalNotesIn an earlier episode, we explained how we started our voice journey and enabled Voice control with bol.com (Ok Google)Google Dialogueflow

Introduction Another week another book discussion. Maybe we can start a second Techlab Podcast dedicated to interesting books? We got some great responses on the last week's episode about team topologies and we had a good opportunity. So it is time for the Never Split the Difference - Podcast. In earlier episodes, we talked with YP's about their side projects (behind the mask - platform for the hospital to share experiences and Real-time sales dashboard), about the YP program itself and participating in competitions, the BAPC2020. This time we sit together with representatives of the YP program because they started something really cool.What this episode coversThe YP Bookclub. And why do I think it so cool? Because they came up with a title I wouldn't think of Never split the difference Authors: Chris Voss Tahl Raz. Chris Voss is a former FBI hostage international kidnapping negotiator and in this book he takes you inside the world of high-stakes negotiations, revealing the skills that helped him and his colleagues succeed where it mattered most: saving lives.So, how is this relevant to our YP's in bol.com?First, we discuss the idea behind the YP Bookclub and the format.After that, we dive into the book and what the learnings are.We connect these learning to the daily job of engineers in general and Young Professionals in particular. And think about how Never split the Difference - podcast could be interesting for you.GuestsPriyanka Radja; Software Engineer • IT - Selling Assortment Fintech – Offer HighwayChris Langhout; Software Engineer • IT - Selling Assortment Fintech – Offer HighwayNotesAkerman model – 65% of the price, 85%, 95%. Increments from big to smaller.Black Swan TheoryBook: Socrates op Sneakers

Introduction A lot of people involved in the design and structuring of organizations could learn a lot from the book Team Topologies. Our guest describes it in the episode a Domain Specific Language (DSL) for organizational design and evolution. The header of the website and the subtitle of the suggest that it is the way for organizing business and technology teams for fast flow. In the episode, we discuss the 4 kind of teams and the 3 ways of interactions between these teams that are at the core of Team Topologies.What this episode coversBesides that, we cover the fundamental topics like Conway's Law, Cognitive Load and share examples of the use at bol.com.GuestsEduardo da Silva - Space Tech Lead and sociotechnical architectNotesBlog post by Eduardo on Team TopologiesThe book Team TopologiesOur previous podcast on sociotechnical architecture

Introduction It sparked in the episode Interactive heavy applications we should record a podcast episode on TypeScript. Around the same time, we came in contact with Hackages. A company focusing on learning tech.What this episode coversTime to bring the engineers together and dive deeper into TypeScript.Typescript is mentioned amongst the 5 most promising languages in 2020.We talk about:What is typescript and how do you benefit?What are good implementation strategies?Bol.com examplesExamples from HackagesMaturity in the usage of TypescriptGuestsNiels van Midden; Front End software engineer at bol.comDavy Engone; Software Engineer at Hackages (the– The guy that is going to make you use/adapt TypeScriptKasper Peulen; Fullstack engineer at bol.com with focus on Front EndNotesRefactoring your code blogpost, one of the areas typescript is being used in bol.comTypescript home

Introduction We want to share our approach to IT to learn and entertain you. In this episode, we are happy to have an external guest at the table discussing with our internal guest. GraphQL stands for Graph Query Language and is used for interacting with services from the frontend. We are talking about API's here.What this episode coversExplore with us the possibilities this approach has to offer and how it could even help you to speeds up innovation in the front-end.Like our guest mentions:GraphQL is a specification not an implementationTopicsWe discussed the following topicsWhat is GraphQL?What problems does it solve?When should you avoid it?Do you need additional security measures?How is it used at bol.com?What is (a)typical for the use of this Query Language at bol.com?What does a development team need to get started?How do you document what you can query?What is the future?GuestsAlbert Groothedde - Software engineer Frontmen / Rabobank used GraphQL both on front-end and back-end side at several clientsEduardo Gomez - Software engineer used GraphQL on the back-end side.NotesFalcor JS - NetflixGraphQL vs. Falcor (Netflix)Apollo GraphQL Data Graph Platform

Introduction No rhythm like algorithms. We have been talking in the podcast about programming contest before. For example, about our own Spaces Championship and Advent of code, which also takes place at the end of the year.What this episode coversToday we'll be talking to some participants in the BAPC - The Benelux Algorithm Programming Contest.Like stated on the website of BAPC, it is a contest in which about 90 teams from leading universities in Luxemburg, Belgium and The Netherlands participate. The teams have to solve a series of algorithmic problems and puzzles. The BAPC 2020 was held on December 12th at the Delft University of Technology and is organized by Mathematics Informatics Study Association ‘Christiaan Huygens'Topics discussed:What is BAPC2020?Serious businessStrict rulesTwo bol.com teams competing, why?How is it organized? Virtual, gathering?What kind of problems to solve?Should you be an experienced SE?Our own bol.com spaces championshipAnd the main question: will the hosts of the show compete in an upcoming championship?GuestsNena O'Driscoll; Young Professional, joined several bol.com and participated in one uni programming competition before, but never the BAPCBas van Rooij; Young Professional, joined several bol.com programming competition before, but never the BAPCNotesScoreboard of BAPC 2020BAPC2020 on youtube, get an idea on the live scoreboardBlog: The Dutch Software Testing Championship

Introduction It happens a lot that listening to a podcast sparks new questions. So, after our episode on Front-End quality, we wanted to know more about Storybook. This coincided with some people reaching out to us to collaborate in the podcast.What this episode coversAnd look where we are now: creating a new podcast on this subject. We asked our selves the question: Could it be the holy grail for front end development?Topics discussed:What is Storybook?What problems does it solve?How does it support app development?What does the Add-on ecosystem look like?Is there a way to do accessibility testing?How do we at bol.com use this tool?What future developments can we expect?GuestsYann Braga (twitter)- Senior Front-End Engineer at FrontMen; Contributor to Storybook.Niels van Midden - Front-End engineer at Bol.com in the checkout team.NotesThe Storybook page.The presentation at Codemotion by Yann.Yann is building a Storybook course together with newline.co; Keep an eye on their website for the release.

Introduction Weaving a Service Mesh for Multiple Clusters at bol.com - that was the title for the presentation our guests gave during the virtual KubeCon and CloudNativeCon 2020 earlier this year. This triggered our curiosity. We have questions like what is this service mesh about? Why do we need it? How did we implement it?.GuestsRemco Overdijk; Tech Lead Provisioning Fleet / Expert System Engineer at bol.com. You might know him from the episode where we spoke about Kubernetes.James Brook; Cloud Solutions Architect at GoogleNotesCNCFIstioRemco and James presenting at KubeCon/CloudNativeCon 2020