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Hopefully you’re already signed up, but in case you’ve missed the invitation, on Thursday 21st June we’re running an evening of talks focused on Serverless and Microservices. In our first talk, Rafal Gancarz will be discussing ‘What is Serverless and why should you care’; our second speaker, Kate Stanley, will then present her talk ‘Securing Microservices: a practical guide’. Ahead of the event we managed to have a quick catch up with both Kate and Rafal to get the lowdown on what to expect.

Starting with our first speaker; Rafal is a versatile technologist with several years of commercial experience building high quality distributed systems; a technical architect with broad expertise in numerous architectural styles and patterns, as well as excellent hands-on developer. He’s also a Certified Scrum Master, experienced agile practitioner and evangelist, passionate about improving project delivery and building highly performing teams. We chatted about the questions we can expect to get the answers to and his advice for new developers.

1. Who do you think should come along?

Anybody interested in the future of software delivery or cloud computing. Serverless Computing has huge potential to be the new software delivery paradigm and now is the time to learn what the future of our industry may look like.

2. What do you think are the three most interesting questions that this event will answer?

What is Serverless and Function-as-a-Service?
How FaaS integrates with other Serverless services?
How software is likely to be delivered in the future?

3. Why do you think this presentation is important for people?

I believe that most IT practitioners are mostly familiar with OS runtime oriented or container based software delivery, and haven’t been exposed to Serverless Computing yet; but the industry is moving towards cloud-native architectures, beyond traditional IaaS based paradigm. While containerised application deployments are slowly going mainstream, the next step for many workloads will be Serverless Computing; many organisations can fast-forward their cloud adoption by adopting the Serverless delivery model rather than investing in labour intensive and rather complex container-oriented platforms.

4. Any advice for junior developers entering the industry?

I believe individuals new to the industry should first and foremost invest their time in cloud technologies. Serverless Computing in particular is one of the very promising areas that will have a massive impact on the future of the IT industry. It’s quite likely many junior developers starting their careers in near future will be exclusively working with cloud technologies including Serverless Computing and may not experience much of OS/IaaS based software development at all.

Moving on to our second speaker; Katherine Stanley is a Software Engineer on the microservices team for WebSphere Liberty. As a part of the Liberty team she has created samples to help developers get started with microservices and worked on the open source microservice project GameOn. Katherine has also given presentations and run workshops about microservices and GameOn at European conferences, including DevoxxUK and OSCon in London, and JFokus in Sweden. Katherine has been at IBM since 2014 and is based in the Hursley UK lab. We found what we can expect to learn and why the presentation is important.

1. Who do you think should come along?

Any developers who are starting to create microservice based applications and aren’t sure where to start when it comes to securing those applications in this new architecture choice.

2. What do you think are the three most interesting questions that this event will answer?

This event will answer:
What parts of my application do I need to secure?
What techniques can I use to secure my application?
What libraries and platforms are available to make it easier?

3. Why do you think this presentation is important for people?

The shift to microservices has meant that developers are owning the full stack of an application, which includes security. It is much more effective to add security as you develop your application, rather than trying to add it all at the end, so knowing what to consider as you build your application is very important.

4. Any advice for junior developers entering the industry?

There are lots of libraries and platforms available, so don’t write everything yourself, look for a library or platform to help make your life easier.

If you’d like to join us at the event, it’s happening on Thursday 21st June, 18:30 – 21:00 at Skills Matter, EC2M 7EB and is kindly sponsored by the folks @RecWorks and @skillsmatter. You can find all the registration details here:

You can also find both our speakers on Twitter @RafalGancarz and @KateStanley91


On Thursday 14th June, we’re delighted to be hosting an evening of talks with IBM- Towards a General Theory of Intelligence & What’s New for Java in the Cloud.

In our first talk, ‘Towards a General Theory of Intelligence’, Peter Morgan will take a look at the latest developments in AI research and implementation.

Peter MorganIn our second talk, Steve Poole will discuss how the application stack, open source technologies & the Java ecosystem is changing to meet the demands of Cloud. Whether improved memory footprint, new operating modes, different deployment models or even new hardware the future of Java in the Cloud is demanding more than ever before. This talk will help you understand the economic and technical forces driving the evolution of Java and will show you a future that’s even more amazing than you might imagine.

Ahead of the event we caught up with Peter to find out what we can expect during his talk and why it’s important.

1. Who do you think should come along?

Anyone interested in artificial intelligence (everybody?), and developments thereof.

2. What do you think are the three most interesting questions that this event will answer?

i. What is intelligence?
ii. How much can we presently describe theoretically?
iii. How do we get to AGI (Artificial General Intelligence)?

3. Why do you think this presentation is important for people?

It will get people thinking about the true nature of intelligence and how we might build it.

4. Any advice for junior developers entering the industry?

Learn as much about AI as humanly possible.

If this has stoked your interest, the event is happening on Thursday 14th June, 18:00 – 21:00 at IBM, 76/78 Upper Ground, London, SE1 9PZ . If you’d like to RSVP, you can find all the details and register here:

On Tuesday 12th June we’re running an event with a difference. Together with our guest speaker Barry Evans, we’ll spend a couple of hours solving fun Java challenges, getting a clear understanding of what causes the most stressful Java bugs, and having fun eliminating them from our projects.

wXUS8yMB_400x400We’ll use this series of Java puzzles and challenges as a way to learn concepts and save loads of time finding those tricky bugs.

This event is ideal for anyone with an interest in removing the pesky bugs that are a daily stress in their work as Java developers!

Barry is a seasoned web application engineer with over 10 years’ experience developing enterprise applications predominantly in the financial sector. Presently, he is an Oracle Certified Senior Applications Consultant at DubJUG partner Version 1, where he has been using Java SE, Spring, and ORM to build middleware for RIA apps written in Adobe Flex & AS3, Angular JS, and HTML 5.

Ahead of the event we caught up with Barry and found out all about the event and to get his advice for new developers.

1. Who do you think should come along?

I believe that Java developers of all skill levels can take something away from the session. There are challenges on a wide range of features the JDK has to offer; from Strings, to Threads, to OOP, and everything in between.

Newcomers to the language and veteran users of the JDK alike are sure to walk away a better bug hunter. Even if you know the Java language inside out, being able to read a short code snippet and determine the outcome quickly is tricky, but great for honing your skills, and most of all, fun!

2. What do you think are the three most interesting questions that this event will answer?

i. Can I become a better Java developer, and have fun?
ii. Is bug finding a chore… or a joy?
iii. Is there a new feature of the JDK I can use on my current project?

3. Why do you think this presentation is important for people?

It’s important to take some time away from your day to day job as a Java developer, possibly spending most of your time working on large-scale enterprise applications, and have some fun solving trivial problems.

The audience will be working on small coding challenges which makes for a highly interactive session. This introduces a unique approach compared to conventional presentations, which can end up being a one-way conversation between the presenter and the audience.

The Java Challenges turn the focus back on to the audience, and the most successful coders learn from doing, not listening.

4. Any advice for junior developers entering the industry?

Get Certified!

One of the main reasons I am giving this presentation is because I studied for the Java SE 8 OCA & OCP certifications. During that study, I was inspired not just by the technical topics covered, but also by the author’s writing style, and their approach to problem-solving.

My experience on the pathway to certification introduced me to many opportunities I would not normally have had, meeting and collaborating with very talented individuals along the way. Don’t consider becoming Java certified as the end, it is only the beginning.

If you’d like to join us at the event it’s happening on Tuesday 12th June, 18:30 – 21:00 at David Game College, EC3N 2ET and is kindly sponsored by the folks @RecWorks. You can find all the registration details here:

You can find Barry on Twitter: @Bazza_NI

On Tuesday 5th June we’re running a new event focused on Java Memory Leaks, and in particular, solving these in under 10 minutes (sounds good to us!). We’ll be using a consistent methodology to identify whether you have a heap memory leak, analysing the memory to identify the leak, and determining the cause.

JSWe’re delighted that we’ll be joined at the event by Jack Shirazi from the Performance and Reliability team at Alongside his role at, Jack is the founder of and author of Java Performance Tuning (O’Reilly); he’s been an official Java Champion since 2005 and an LJC member since 2009. As well as authoring his popular book, and contributing to several other books, Jack has published over 60 articles on Java performance for various sites and magazines; over 200 newsletters for over 15 years; and, with these newsletters published around 10,000 Java performance and memory related tips.

Ahead of the event we caught up with Jack; he told us why the session is important, what questions we can expect to learn the answers to and gave us his advice for new developers.

1. Who do you think should come along?

Any Java developer of any level. I provide sufficient detail for any level of developer and this talk shows how to solve a problem that is intermittent, so even if you’ve analysed heaps before it’s useful to get a different point of view and a refresher

2. What do you think are the three most interesting questions that this event will answer?

The event answers: what process you should follow for analysing any Java memory leak; which tools are most useful for analysing Java heap leaks; and how you can identify that you have a leak before (as well as after) a leak becomes an issue.

3. Why do you think this presentation is important for people?

Memory leaks are one of the most common causes of downtime/server crashes/service failure. But, at least for heap leaks, they’re a solved problem – you just need to know what to do about them. But leaks don’t happen often enough that every Java developer will have or remember the skillset to solve the problem quickly. What I’m providing is a step-by-step procedure that you can easily understand then forget about until you need it – then just quickly refresh yourself in minutes and apply to solve the issue very quickly.

4. Any advice for junior developers entering the industry?

Come to this session and add this to your toolset. Then remind yourself before you have an interview, experience of fixing a memory leak is a cool thing to know for interviews.

If you’d like to join us at the event it’s on 5th June, 18:30 – 20:30 at WeWork Old Street, N1 6DR. The event is kindly being sponsored by the folks at Gridgain, WeWork Old Street and RecWorks. You can find all the registration details here:

In case you’ve not been along to one of their events yet, or you’re entirely new to what they do, we wanted to draw your attention to the London In-Memory Computing Meetup. The group is open to everyone and is aimed at those already working with distributed systems or interested in doing so.


We caught up with Tom Diedrich, Director of Community Engagement at GridGain and one of the organisers of the Meetup. Tom told us about why the group was founded, their aims, future plans and gave us his advice for new developers.

What can you tell us about the London In-Memory Computing Meetup? Why did you set it up and why should people join?

I’m one of the organizers of the London In-Memory Computing Meetup, we founded it a couple months ago because we saw an unmet need. The need for a venue for data scientists, database architects, software developers, CTOs — and everyone else — using or interested in learning more about in-memory computing, Big Data, Fast Data, IoT and HPC solutions. This includes use cases, best practices, and more. It may be of interest to you if you are already working with distributed systems, planning or interested in doing so.

What about the future – What is your longer term vision for the group? Can you give us any spoilers about what to expect?

Well, this group is open to everyone and we’ve already had leading in-memory computing experts from Oracle, GridGain and VoltDB speak at the London meetup. My longer-term vision for the group is to have users share their challenges, successes and lessons learned from the trenches.

On the larger scale I’d love to grow awareness about in-memory computing in general. And this meetup will be showcasing, on a regular monthly cadence, the latest news in this rapidly growing ecosystem. So attending these meetups gives members an advantage in that they are informed about not only what’s currently available, but also what is coming up from vendors and users (companies using these technologies) from around the world.

I also see the meetups as a way of drawing attention to the annual In-Memory Computing Summit Europe conferences. The next one will be in London June 25-26. The conference is a natural extension of the London In-Memory Computing Meetup.

Obviously being in a community engagement role you meet with loads of the industries best developers – from your experience what advice would you have for more junior developers about how to get the best out of their career?

I’d recommend that they join the open-source Apache Ignite community, download the latest version and start by saying “Hello” to everyone in the community via the dev mailing list. The project has a very friendly and active group and it’s the perfect place for junior developers to learn. The volunteers are a very nurturing bunch and some of the best developers in the world.

For more information, please visit the London In-Memory Computing Meetup page –

On Thursday 24th May, we’re running an event where we’ll be discussing Upcoming Java Language Changes. We’re delighted to welcome Stephen Colebourne, Engineering Lead, Platform at OpenGamma, the creators of Strata.
Specifically, we’ll be considering what Java language changes are on their way and how will they make your coding life easier?

We’ll also take a look at a range of new features being developed by Project Amber and Project Valhalla to get a good overview of Java’s future. Come along and be prepared to give your opinions on the new features!

Ahead of the event we had a chat with Stephen; he gave us his view of why the event is important, who should join us and some tips for junior programmers.

1.Who do you think should come along?

The talk is a sneak peek into the future of the Java language, where plans exist but nothing is fixed. If you actively code Java and are interested in how the language is going to get better, this is your opportunity to see and think about the future. I might well take some straw polls on the more controversial ideas too!

2. What do you think are the three most interesting questions that this event will answer?

What language changes are coming, how will they work in practice, and
are the right design choices being made?

3. Why do you think this presentation is important for people?

While many teams have been slow to adopt new versions of Java in the past, Oracle is trying to reduce that flexibility by reducing the number of overlapping supported versions. As such, you may end up using these new language features sooner than you might have thought you would!

4. Any advice for junior programmers entering the industry?

Being a software engineer is about much more than just writing code. It’s about the bigger picture, including maintainability, quality consistency and knowing what trade- offs to make. Take the time to listen to those around you and review your own work – that self – awareness will be key to success.

If you’d like to join us at the event it’s happening on Thursday 24th May, 18:30 – 21:00 at David Game College, EC3N 2ET and is kindly sponsored by the folks @RecWorks. You can find all the registration details here:

If you’d like to, you can also find Stephen on Twitter: @jodastephen

On Wednesday 9th May, we’re running an evening of presentations and live demos, all focused on Reactive Microservices with Micronaut and Open Cloud-Native Java. In our first talk, Graham Charters will give a presentation and live demonstration of how the MicroProfile initiative helps you build cloud-native Java microservices on open source, open standard APIs and, avoid lock-in to a single company. Then, Alvaro Sanchez-Mariscal will be discussing Reactive Microservices with Micronaut.

In preparation for the event we caught up with Graham and Alvaro. An IBM Senior Technical Staff Member and WebSphere Applications Server Developer Advocacy Lead, Graham takes a keen interest in emerging technologies and practices, and in particular programming models. His past exploits include establishing and contributing to open source projects at PHP and Apache; and participation in, and leading, industry standards at OASIS and the OSGi Alliance.

Alvaro Sanchez-Mariscal is a passionate developer and agile enthusiast with over 18 years’ experience. He now works as a Software Engineer at Object Computing (OCI), the company leading Groovy, Grails and Micronaut open-source development. Before working at OCI, Álvaro gained a wealth of experience across various industries and businesses; from gambling games to fintech, founding his own company, and working at organisations such as IBM BCS, BEA Systems and Sun Microsystems. Álvaro is also a speaker at conferences including GeeCON, JavaLand, JavaZone and Codemotion. You can find him on Twitter @alvaro_sanchez They gave us a summary of their ambitions for the event, the latest technology and words of wisdom for junior programmers.

1. Who do you think should come along?

GC – This talk should be of interest to Java Developers and Architects looking to develop, deploy and manage modern cloud-native Java microservices. The technologies the talk will focus on are the result of broad industry vendor and user collaboration. They also benefit from having multiple implementations, which means broader input to the design, and greater choice for users.

ASM- Micronaut is a brand new framework for the JVM, so we don’t expect any prior knowledge. Any Java developer is welcome!

2. What do you think are the three most interesting questions that this event will answer?

GC – The first question this talk will answer is, what is cloud-native, how did we get there, and what to look for in an environment to help me? Okay, maybe that’s three questions in one. Understanding how the industry evolved to cloud-native and the characteristics is an important foundation to choosing the right technologies and increasing the chances of success when embarking on a cloud-native journey.

The second question this talk will answer is, what is MicroProfile and how does it help me address the challenges of cloud-native? Based on the understanding established in answering the first question, this talk will introduce the MicroProfile technologies and, along with the use of demos, show how each helps in the development and management of cloud-native applications.

The third question this talk will answer, and some (ok, not many) would say the most important, is whether or not cloud-native should be hyphenated.

ASM – As we are introducing a new technology, the session will give the audience an idea of what Micronaut is and how can they use it in their projects.

They will also learn about Micronaut features that are similar to the ones in other frameworks like Spring and Grails. They should feel at home with Micronaut. Finally, attendees should understand that by using Micronaut they get the best of two worlds: the developer experience and productivity of frameworks like Spring Boot or Grails, and the performance of a compile-time reactive framework based on Netty.

3. Why do you think this presentation is important for people?

GC – As an industry we’ve made huge advances in how we deliver solutions, for example through Agile, DevOps Cloud and Microservices. These advances are the cornerstones of cloud-native. What is sometimes not immediately clear, is what this means in terms of the resulting impacts on how we develop, deploy and manage these modern cloud-native applications. This presentation will help people gain an appreciation of the new challenges and offer open technology choices for how to address them.

ASM – Micronaut was first announced in February and is still not yet public. We are still polishing some things before the first public milestone, which will be published in a matter of weeks. This is a unique opportunity to learn about it!

4. Any advice for junior programmers entering the industry?

GC – My advice to junior programmers entering the industry would be to not be afraid to ask questions; take every opportunity to learn something new. A strong technical foundation will stand you in good stead for the future. Lastly, understand what you enjoy and what motivates you and don’t lose sight of that as you seek to progress your career. If programming is what gives you the buzz, be the best programmer you can be.

ASM – The JVM ecosystem is quite crowded with excellent frameworks and sometimes the number of options are overwhelming. In my opinion, what makes the difference between a good developer and a great one is the ability to judge which technology is the best choice to solve a particular problem. To get this skill they should constantly learn about new technologies. Meetups like this at the LJC are a very convenient way to learn.

Reactive Microservices with Micronaut & Open Cloud-Native Java is happening on 9th May, 18:00 – 21:00 at IBM UK, SE1 9PZ. If you’d like to join us, please register here:


If you don’t already know, jPrime’s 4th conference at Sofia Tech Park, Bulgaria is coming up in less than a month (29th and 30th May). For those who are new to jPrime, it’s a conference focused on Java, various languages on the JVM, mobile, web and best practices. It’s run by the Bulgarian Java User Group and backed by some major businesses. Visitors have the opportunity to listen to some of the best international speakers, as well as presenters from Bulgaria and the Balkans. It’s not all work though… there’s also plenty of time for hacking, networking and fun.

In case you can’t tell, we’re a tad excited about jPrime. Ahead of the event we caught up with one of the organisers Ivan St Ivanov who gave us the lowdown on all things jPrime.

Ivan is the Co-Founder and Senior Programmer at VIDA Software, he also does a variety of consultancy roles, teaches Java and Microservices courses, is an active JUG member and is studying for a PhD in the field of Cloud Multi-Tenancy… we’re seriously impressed.

Here’s what we learnt:

  • jPrime is organised by a group of true enthusiasts – all profits go back into the next year’s JUG events, the organisers do it for the love of it.
  • Now in its 4th year, the conference has grown into a 2-day event with over 700 attendees.
  • The organisers come with a massive range of interests and areas of expertise. There are those that are most interested in the current hype (e.g. hmm, Kotlin, Spring 5 + Reactor, Blockchain); there are also people (Ivan being one of them) that are evangelical about the MicroProfile, and another lead who is active in the OSGi community.
  • There’s a jam-packed agenda, far too many to list, but safe to say, all things Java, languages on the JVM, mobile, web and best practices are explored by some excellent speakers.

And if that’s not enough…

  • The weather in Sofia around jPrime is typically beautiful so it’s a great opportunity to get out and explore the beautiful capital of Bulgaria. It has a long ancient history, so there’s plenty to see outside of the conference.

We managed to get our hands on some tickets for jPrime, and in the spirit of sharing the love we’d like to give them away. If you’d like to be in with a chance of winning a ticket to this year’s conference, you can enter the raffle here – You can see all the details, including the agenda for jPrime here: and you can find Ivan on Twitter at @ivan_stefanov

On Tuesday 8th May, we’re running an event focused on Java 9 and Java 10. We’ll review their features in three parts: improvements, additions, and advances; specifically, we’ll look at improvements and additions to the language that are not only exciting, but also useful for everyday programming. We’ll be using live coding to illustrate the concepts and their benefits.


We’re really pleased to be joined at the event by Dr. Venkat Subramaniam. Venkat is, amongst other accolades, an award-winning Author; Founder of Agile Developer, Inc.; Creator of; and an instructional Professor at the University of Houston. He has trained and mentored thousands of Software Developers in the US, Canada, Europe, and Asia, and is regularly invited to speak at international conferences. Venkat’s overarching aim is to help his client’s software projects to succeed through the use of sustainable agile practices.

In preparation for the event we had a chat with Venkat and got his view on the session, the latest technologies and advice for aspiring programmers.

1. Why do you think this presentation is important for people?

A lot of the focus on Java 9 has been around Modules. That’s important, but there are a number of other interesting and useful aspects to Java 9 and 10 as well; learning about these can help us with the design and implementation of code in modern Java.

2. Who do you think should come along?

Bring along a friend, a colleague, a relative, a child – just about anyone who would benefit from meeting other Developers. If you’re a Programmer, Lead Developer or Architect on any projects that use Java, and you’re curious about the more recent features of the language, this presentation is for you.

3. What Java/JVM technologies are interesting you most at the moment?

Quite a few, but I’ll mention just one here. I’m really excited about where Reactive programming is heading.

4. Any advice for junior programmers entering the industry?

A professional who doesn’t learn to fail, fails to learn. Ask your colleagues to critique your work and improve based on the feedback they provide. Regularly attend user group events. It is never too early to get involved in the community.

Java 9 and Java 10: The Key Parts, is happening on 8th May, 18:00 – 21:00 . If you’d like to join us, please register here:

Venkat is a (co)author of multiple technical books, including the 2007 Jolt Productivity award winning book ‘Practices of an Agile Developer’. You can find a list of his books at You can also reach him by email at or on twitter at @venkat_s.

The first in a series of interactive sessions discussing the state of garbage collection in 2018 takes place on May 1st. Experts including Martijn Verburg, Richard Warburton and John Oliver will be taking part, sharing their knowledge on all things garbage collection related. We spoke to Martijn and Richard to get their take on the event.

1. Who do you think should come along?

MW: Any Java developers (or developers who write code on the JVM) who care about how their code performs on the JVM, especially in small (e.g. uService apps) or large (e.g. Big Data style apps)
RW: Java developers who have a solid grasp of the basic language and tool chain and want to understand more about how the JVM works under the hood and how to make better use of the garbage collection subsystem.

2. What is your background in GC?

MW: I’m the CEO of jClarity, a tooling company that specialises in GC analysis. I have a decent understanding of GC algorithms and performance tuning, but certainly not at the level of the world’s experts (some of who are in jClarity’s engineering team)!
RW: I’ve worked previously (and currently) for JVM tool vendors who wrote tooling around GC logs and understanding GC. I’ve also done bespoke development and consulting work on problems that have low latency requirements and thus have an interaction with GC tooling.

3. Why do you think it’s such an important topic to get right?

MW: When Java Garbage collects it often has a Stop the World (STW) phase, which brings the whole JVM to a stop, this can greatly impact end user / system experience depending on how often those pauses occur and how long each pause occurs for.
RW: Performance is a big driver of business value. To put it simply happy customers are a great thing to have and customers aren’t happy when their website is unresponsive. It can also be a strong driver of business value in spaces such as AdTech or HFT where low latency really matters.

4. What do you think are the three most interesting questions that this event will answer?

1) What has changed in Java 9+ with regards to GC behaviour?
2) What’s the future direction of GC in Java?
3) How do I tune GC for my small container based uService apps?
1) How do I know when I have a GC problem?
2) What is changing around GC in future Java versions?
3) How do I understand when to look at GC rather than other application problems.

5. Any advice for junior programmers entering the industry?

MW: Whatever they tell you, it’s a people problem! So even with a technical event like a GC Panel, there’s always a strong human element. How does GC impact people, what performance characteristics do people care about? How do we help people tune etc?
RW: Have fun.

The Garbage Collection 2018 event promises to be an interesting and informative evening, so come along and see what you can learn. It’s a great opportunity to join in with an analysis of changes in Java 9, tuning your application, extracting information out of the JVM, tooling to aid interpretation, and looking at and beyond OpenJDK/Oracle JDK.
You’ll also be able to find out about the best sources of garbage collection information and where to find them.

If you are involved with garbage collection in any capacity within your organization, or you just have an interest in the topic, this is a chance to increase your understanding and advance your knowledge.

If you’re interested, then sign up to reserve your place:, and join the Slack Group at

What is the LJC

The London Java Community (LJC) is a group of Java Enthusiasts who are interested in benefiting from shared knowledge in the industry. Through our forum and regular meetings you can keep in touch with the latest industry developments, learn new Java (& other JVM) technologies, meet other developers, discuss technical/non technical issues and network further throughout the Java Community.