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Microservices Anti-patterns: It’s All About the People

April 18, 2018 | Microservices

Microservices Anti-patterns: It’s All About the People

Quite a few of the anti-patterns we observe today on microservices projects are strongly related to how people approach the problem. Given their nature, these anti-patterns tend to be deeply ingrained and self-sustaining. Addressing them starts with increased awareness and by changing ways of approaching the problem, rather than by the introduction of yet another technical tool or framework.

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Patterns of Successful Cassandra Data Modelling

September 6, 2016 | Cassandra

Patterns of Successful Cassandra Data Modelling

A growing number of clients are asking OpenCredo for help with using Apache Cassandra and solving specific problems they encounter. Clients have different use cases, requirements, implementation and teams but experience similar issues. We have noticed that Cassandra data modelling problems are the most consistent cause of Cassandra failing to meet their expectations. Data modelling is one of the most complex areas of using Cassandra and has many considerations.

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Terraform Infrastructure Design Patterns

September 14, 2015 | Cloud, DevOps

Terraform Infrastructure Design Patterns

If you are operating in the programmable infrastructure space, you will hopefully have come across Terraform, a tool from HashiCorp which is primarily used to manage infrastructure resources such as virtual machines, DNS names and firewall settings across a number of public and private providers (AWS, GCP, Azure, …).

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Agile Ex Meet Up – Coaching at the Organisational level

May 24, 2022 | Software Consultancy

Agile Ex Meet Up – Coaching at the Organisational level

Watch Simon Copsey’s talk from the Agile Ex Meetup on “Coaching at the Organisational Level” where he explores some of the common downward spirals in IT and the larger organisation, as well as the tools that coaches and individuals can use to surface and discuss them in a way that allows for systemic change, even without formal authority.

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Kafka vs RabbitMQ: The Consumer-Driven Choice

July 20, 2021 | Blog, Data Engineering, Kafka

Kafka vs RabbitMQ: The Consumer-Driven Choice

Message and event-driven systems provide an array of benefits to organisations of all shapes and sizes. At their core, they help decouple producers and consumers so that each can work at their own pace without having to wait for the other – asynchronous processing at its best.

In fact, such systems enable a whole range of messaging patterns, offering varying levels of guarantees surrounding the processing and consumption options for clients. Take for example the publish/subscribe pattern, which enables one message to be broadcast and consumed by multiple consumers; or the competing consumer pattern, which enables a message to be processed once but with multiple concurrent consumers vying for the honour—essentially providing a way to distribute the load. The manner in which these patterns are actually realised however, depends a lot on the technology used, as each has its own approach and unique tradeoffs. 

In this article we will explore how this all applies to RabbitMQ and Apache Kafka, and how these two technologies differ, specifically from a message consumer’s perspective.

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Automation of complex IT systems

May 14, 2020 | Blog, DevOps

Automation of complex IT systems

At the time of this post, the UK is making steps to exit from an unprecedented lockdown measures for the Coronavirus. Much of the UK workforce are still making efforts to work-from-home with mainly key workers operating – at risk – in public. Many industries have shut down completely. Consequently, many businesses are reflecting on what happens next and how do we better mitigate future pandemic events?

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It’s 2020, can I have my ML models now?

April 2, 2020 | Machine Learning

It’s 2020, can I have my ML models now?

Recent years have seen many companies consolidate all their data into a data lake/warehouse of some sort. Once it’s all consolidated, what next?

Many companies consolidate data with a field of dreams mindset – “build it and they will come”, however a comprehensive data strategy is needed if the ultimate goals of an organisation are to be realised: monetisation through Machine Learning and AI is an oft-cited goal. Unfortunately, before one rushes into the enticing world of machine learning, one should lay more mundane foundations. Indeed, in data science, estimates vary between 50% to 80% of the time taken is devoted to so-called data-wrangling. Further, Google estimates ML projects produce 5% ML code and 95% “glue code”. If this is the reality we face, what foundations are required before one can dive headlong into ML?

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10 Pieces of Borrowed Wisdom for Effective Tech Consultancy

August 29, 2018 | Software Consultancy

10 Pieces of Borrowed Wisdom for Effective Tech Consultancy

My last year or so here at OpenCredo has involved a very well-supported first foray into tech consultancy. Different engagements pose both unique, as well as familiar challenges for me as a consultant, all of which played a part in shaping and moulding the way I understand and approach problems. This blog is a brief collation of wisdom that’s helped me the most during this adventure; gained by learning the hard way, as well as that acquired from mentoring and colleagues who have gone before. The shared wisdom has made me a much more effective consultant, and kept me sane in the process, for which I’m very thankful.

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The Power of the Architecture-driven Organisation

July 13, 2018 | Software Consultancy

The Power of the Architecture-driven Organisation

As a consultant I often find myself in situations that require tricky problem solving, typically of a technical nature. Yet although it is common to approach a consultancy engagement in terms of its technical context, not all problems have a purely technical solution.

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Heuristics for Identifying Service Boundaries

May 16, 2018 | Microservices

Heuristics for Identifying Service Boundaries

To identify service boundaries, it is not enough to consider (business) domains only. Other forces like organisational communication structures, and – very important – time, strongly suggest that we should include several other criteria in our considerations.

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[Past event] Kafka Summit London 2018

We are excited to announce that our Lead Consultant, Pergerto Fernandez is presenting at Kafka Summit London 2018! Kafka Summit is the premier event for data architects, engineers, devops professionals, and developers who want to learn about streaming data.

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[Past event] Muon User Group #1

We are excited to be hosting the first Muon User Group at our London office for an Intro to Muon – How to build Polyglot Message and Event Microservices!

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Data Analytics using Cassandra and Spark

March 23, 2017 | Cassandra, Data Analysis, Data Engineering

Data Analytics using Cassandra and Spark

In recent years, Cassandra has become one of the most widely used NoSQL databases: many of our clients use Cassandra for a variety of different purposes. This is no accident as it is a great datastore with nice scalability and performance characteristics.

However, adopting Cassandra as a single, one size fits all database has several downsides. The partitioned/distributed data storage model makes it difficult (and often very inefficient) to do certain types of queries or data analytics that are much more straightforward in a relational database.

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Google Cloud Spanner: our first impressions

March 7, 2017 | Data Analysis, GCP

Google Cloud Spanner: our first impressions

Google has recently made its internal Spanner database available to the wider public, as a hosted solution on Google Cloud. This is a distributed relational/transactional database used inside for various Google projects (including F1, the advertising backend), promising high throughput, low latency and 99.999% availability. As such it is an interesting alternative to many open source or other hosted solutions. This whitepaper gives a good theoretical introduction into Spanner.

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[Past event] Voxxed Days Bristol 2017

Join Lorenzo Nicora at Voxxed Days Bristol 2017 for his talk on Event Sourcing and CQRS! Voxxed Days is a series of tech events organised by local community groups where local and international speakers converge at a wide range of locations around the world. This means each event retains a unique regional flavour, whilst being part of the overall Voxxed movement. Topics covered at Voxxed Days fall under the same radar as Voxxed.com, including: Server Side Java, Java Language, Cloud and Big Data, Web & HTML, Mobile, Programming Languages, Architecture & Security, Methodology, Culture and Future Technologies.

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Event Replaying with Hazelcast Jet

February 13, 2017 | Data Engineering

Event Replaying with Hazelcast Jet

One of the stated intentions behind the design of Java 8’s Streams API was to take better advantage of the multi-core processing power of modern computers. Operations that could be performed on a single, linear stream of values could also be run in parallel by splitting that stream into multiple sub-streams, and combining the results from processing each sub-stream as they became available.

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[Past event] OOP Konferenz 2017

Join Andrew Morgan  and Daniel  Bryant at OOP Conference 2017! By combining software and business, OOP Conference 2017 is the meeting point for people who work primarily in the enterprise environment. Technical experts (architects, developers, business analysts, and testers), technical (project) managers and leaders gain an excellent view on the state-of-the-art in modern software engineering. […]

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[Past event] Microservices Meetup Munich – Deadly Sins and Effective Testing

Our Chief Scientist, Daniel Bryant and Consultant Andrew Morgan will be heading to Munich for the Microservices Meetup on the 1st of Feb. The night will kick off at 6:30pm at Einstein Kultur with drinks and pizza, talks from Daniel and Andrew on microservices and effective testing will then follow from 7pm.

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The Three ‘R’s of Distributed Event Processing

January 25, 2017 | Cassandra

The Three ‘R’s of Distributed Event Processing

One of the simplest and best-understood models of computation is the Finite State Machine (FSM). An FSM has fixed range of states it can be in, and is always in one of these states. When an input arrives, this triggers a transition in the FSM from its current state to the next state. There may be several possible transitions to several different states, and which transition is chosen depends on the input.

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[Past event] London HashiCorp Meetup #7

The London HashiCorp meetup is back on this month! Join us for drinks and pizza, and some great talks by Andrew Brown, Senior Software Engineers at Just Eat and James Nugent from Hashicorp.

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[Past event] µCon 2016: The Microservices Conference

Join Daniel Bryant and David Borsos at µCon 2016 on Monday the 7th and Tuesday the 8th of November at CodeNode in London. µCon 2016 is an opportunity to learn about emerging technologies and approaches, share challenges and evolve practices and ideas. Share the challenges you are facing, the technologies you are exploring and the skills […]

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[Past event] O’REILLY: OSCON 2016

Join Daniel Bryant at O’REILLY’S everything open source conference, OSCON 2016 for his talk “The Seven (More) Deadly Sins of Microservices.”

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[Past event] GOTO London 2016

GOTO London is back for the second year running to throw another great conference!   Creating a meeting place for software innovators and thought leaders from startups and enterprises, GOTO London will give you the opportunity to network with people all across different disciplines of software development! With 1 days workshops where attendees can go into depth with […]

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Cassandra – The Good, The Bad and the Ugly Webinar Recording

October 10, 2016 | Cassandra

Cassandra – The Good, The Bad and the Ugly Webinar Recording

In the culmination of our blog series on the topic, on October 6th 2016 OpenCredo Consultants Dominic Fox, Alla Babkina and Guy Richardson, and hosted by Marco Cullen, presented the common design and implementation issues that they have come across in real-world Apache Cassandra deployments.

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[Past event] Webinar: Cassandra – The Good, the Bad and the Ugly

Hear from OpenCredo’s experts in this live Webinar working through best practise and common sense approaches to building out a successful Cassandra cluster, gained through experience working with clients in designing and deploying Cassandra across a wide range of business domains. Learn from them how you can make the very best of your cluster in a real world setting. […]

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Common Problems with Cassandra Tombstones

September 27, 2016 | Cassandra, Data Engineering

Common Problems with Cassandra Tombstones

If there is one thing to understand about Cassandra, it is the fact that it is optimised for writes. In Cassandra everything is a write including logical deletion of data which results in tombstones – special deletion records. We have noticed that lack of understanding of tombstones is often the root cause of production issues our clients experience with Cassandra. We have decided to share a compilation of the most common problems with Cassandra tombstones and some practical advice on solving them.

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[Past event] VJUG24 2016

VJUG24 is the first 24hour virtual Java conference in the world! Find out more and join Daniel Bryant for his talk “The Seven (More) Deadly Sins of Microservices.”

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How Not To Use Cassandra Like An RDBMS (and what will happen if you do)

September 15, 2016 | Cassandra

How Not To Use Cassandra Like An RDBMS (and what will happen if you do)

Cassandra isn’t a relational database management system, but it has some features that make it look a bit like one. Chief among these is CQL, a query language with an SQL-like syntax. CQL isn’t a bad thing in itself – in fact it’s very convenient – but it can be misleading since it gives developers the illusion that they are working with a familiar data model, when things are really very different under the hood.

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[Past event] ThingMonk 2016

Running from the 12th-14th of September, ThingMonk brings together technologists and designers building core infrastructure for IoT for 2 days of great talks by industry practitioners. Join Tareq and Dominic Fox at ThingMonk 2016 and hear them talk about the event sourcing framework, Concursus!

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New Blog Series: Cassandra – What You May Learn the Hard Way

August 26, 2016 | Cassandra

New Blog Series: Cassandra – What You May Learn the Hard Way

At OpenCredo we have been working with Cassandra since 2012 and we are big fans of both open source Apache Cassandra and the capabilities of DataStax Enterprise. Over the years we have collected a great deal of experience throughout the company on how to deliver the benefits of Cassandra in real world projects and have also seen some common pitfalls that businesses have fallen into.

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Kubernetes from scratch to AWS with Terraform and Ansible (part 1)

August 26, 2016 | Kubernetes

Kubernetes from scratch to AWS with Terraform and Ansible (part 1)

This post is the first of a series of three tutorial articles introducing a sample, tutorial project, demonstrating how to provision Kubernetes on AWS from scratch, using Terraform and Ansible.

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Many improvements in Java 8 API for Akka

June 24, 2016 | Software Consultancy

Many improvements in Java 8 API for Akka

Akka has been designed with a Java API from the very first version. Though widely adopted, as a Java developer I think Akka has been mainly a Scala thing… until recently. Things are changing and Akka is moving to a proper Java 8 support.

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[Past event] Infracoders London

Join us for Infracoders London on the 21st of June to hear talks from our Lead Consultant, Bart Spaans and Thoughtwork’s Cloud Specialist, Kief Morris!

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The Concursus Programming Model: State

April 28, 2016 | Software Consultancy

The Concursus Programming Model: State

In a conventional RDBMS-with-ORM system, we are used to thinking of domain objects as mapped to rows in database tables, and of the database as a repository where the current state of every object exists simultaneously, so that what we get when we query for an object is the state that object was in at the time the query was issued. To perform an update, we can start a transaction, retrieve the current state of the object, modify it, save it back again and commit. Transactions move the global state of the system from one consistent state to another, so that the database transaction log represents a single, linear history of updates. We are therefore able to have a very stable, intuitive sense of what it means to talk about the “current state” of any domain object.

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Securing Terraform state with Vault

April 2, 2016 | Terraform Provider

Securing Terraform state with Vault

When it comes to automating the creation of infrastructure in cloud providers, Terraform (version at time of writing 0.6.14) has become one of my core go to tools in this space. It provides a fantastic declarative approach to describing the resources you want, and then takes care of making it so for you, keeping track of the state in either a local file or a remote store of some sort. Various bits of sensitive data is often provided as input to terraform.

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Easy API Simulation with Hoverfly JUnit Rule

March 17, 2016 | Software Consultancy

Easy API Simulation with Hoverfly JUnit Rule

In order to be able to regularly release an application, your automated tests must be set up to give you fast and reliable feedback loop. If bugs are only found during a long and expensive multi-service or end-to-end test run, it can be a hinderance to fast delivery. Unfortunately I have often seen this problem in development environments: a huge suite of clunky, flaky and slow end-to-end tests which test the full functionality of the application as opposed to being more lightweight and reflecting basic user journeys. This produces the “ice cream cone” anti-pattern of test coverage, where unit tests aren’t providing the kind of coverage and feedback they need to.

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Join the OpenCredo Team at the OOP Conference in Germany

January 30, 2016 | Microservices

Join the OpenCredo Team at the OOP Conference in Germany

The OpenCredo team will be presenting two sessions on our recent learnings with implementing microservices at the OOP Conference, which will be running from the 1st – 5th February. We will also be running a booth, and so if you are interested in learning more about our recent projects, are keen to see if we can help you with your latest technical or organisational challenges, or want to join our team, then stop by and say hello!

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The Seven Deadly Sins of Microservices (Redux)

January 8, 2016 | Microservices

The Seven Deadly Sins of Microservices (Redux)

Many of our clients are in the process of investigating or implementing ‘microservices’, and a popular question we often get asked is “what’s the most common mistake you see when moving towards a microservice architecture?”. We’ve seen plenty of good things with this architectural pattern, but we have also seen a few recurring issues and anti-patterns, which I’m keen to share here.

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[Past event] BCS Software Practice Advancement Talk: The Seven Deadly Sins of Microservices

Join Daniel for a brief introduction to the topic of microservices, and also a tour of the nastiest sins (anti-patterns) he has seen in his journey as a consultant on the 6th of April at BCS London.

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[Past event] London HashiCorp User Group Meetup #3

The London HashiCorp Meetup is back on the 19th of May! We give thanks to Huddle for hosting the London HashiCorp Meetup #3, which will be kicking off at the usual time of 6.30pm with pizza and beer. Thomas Doran, Yelp’s Site Reliability Engineer will take the stage at 7pm with his talk, ‘Terraform in […]

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Ruby Web Acceptance Testing Framework

November 23, 2015 | Software Consultancy

Ruby Web Acceptance Testing Framework

Over a year ago, my colleague Tristan posted on the OpenCredo blog about a test automation quick start framework. It’s a prepackaged framework you can clone and get going with testing instantly, rather than wasting your time rebuilding your framework every single project. We have used this framework successfully used on many of our internal projects, and it relies upon a Java, Cucumber-JVM and Selenium stack.

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JavaOne: Debugging Java Applications Running in Docker

November 3, 2015 | Software Consultancy

JavaOne: Debugging Java Applications Running in Docker

My JavaOne experience was rather busy this year, what with three talks presented in a single day! The first of these talks “Debugging Java Apps in Containers: No Heavy Welding Gear Required” was delivered with my regular co-presenter Steve Poole, from IBM, and we shared our combined experiences of working with Java and Docker over the past year.

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Implementing HAL hypermedia REST API using Spring HATEOAS

November 1, 2015 | Microservices

Implementing HAL hypermedia REST API using Spring HATEOAS

To use or not to use hypermedia (HATEOAS) in a REST API, to attain the Level 3 of the famous Richardson Maturity Model. This is one of the most discussed subjects about API design.
The many objections make sense (“Why I hate HATEOAS“, “More objections to HATEOAS“…)
. The goal of having fully dynamic, auto-discovering clients is still unrealistic (…waiting for AI client libraries).

However, there are good examples of successful HATEOAS API. Among them, PayPal.

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The Business Behind Microservices Webinar (Video and Slides)

September 24, 2015 | Microservices

The Business Behind Microservices Webinar (Video and Slides)

Unless you’ve been living under a (COBOL-based) rock for the last few years, you will have no doubt heard of the emerging trend of microservices. This approach to developing ‘loosely coupled service-oriented architecture with bounded contexts’ has captured the hearts and minds of many developers. The promise of easier enforcement of good architectural and design principles, such as encapsulation and interface segregation, combined with the availability to experiment with different languages and platforms for each service, is a (developer) match made in heaven.

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Change is coming to IT

September 21, 2015 | DevOps

Change is coming to IT

The drive for change comes from, everywhere. Within IT departments, developers are asking for more control, and want faster response times than can be provided by traditional gatekeeper IT services. Management hears about new technologies allowing more rapid deployments, better ROI, reduction in costs, increased efficiency, and increased scalability, and they want it for their customers. On top of that, systems age, technologies lose their lustre, and technical debt builds up, while it simultaneously gets harder to recruit people from a shrinking talent pool, all of which creates a case for change from within the technology itself.

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Microservice Platforms: Some Assembly [Still] Required. Part Two

September 20, 2015 | Microservices

Microservice Platforms: Some Assembly [Still] Required. Part Two

Working Locally with Microservices

Over the past five years I have worked within several projects that used a ‘microservice’-based architecture, and one constant issue I have encountered is the absence of standardised patterns for local development and ‘off the shelf’ development tooling that support this. When working with monoliths we have become quite adept at streamlining the development, build, test and deploy cycles. Development tooling to help with these processes is also readily available (and often integrated with our IDEs). For example, many platforms provide ‘hot reloading’ for viewing the effects of code changes in near-real time, automated execution of tests, regular local feedback from continuous integration servers, and tooling to enable the creation of a local environment that mimics the production stack.

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Software Circus: Thinking Fast and Slow with Software Development

September 13, 2015 | DevOps

Software Circus: Thinking Fast and Slow with Software Development

Making Good Decisions within Software

Last week I was privileged to be able to present my “Thinking Fast and Slow with Software Development” talk at the inaugural Software Circus conference in Amsterdam. The conference was amazing, and I’ll write more about this later, but in this post I was keen to share the presentation slides and the thinking behind this talk…

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The Past, Present and Future of Kubernetes

August 7, 2015 | Kubernetes

The Past, Present and Future of Kubernetes

Learning about the benefits of Kubernetes from the Kismatic Team

As part of my writing for InfoQ, I recently had the pleasure of sitting down and chatting with Joseph Jacks and Patrick Reilly from Kismatic Inc, a company offering enterprise Kubernetes support, and asked about their thoughts on the recent Kubernetes v1.0 launch, the history of the project, and how this container orchestration platform may impact the future of microservice deployment.

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Building a Google analytics dashboard with Python3, Tornado and deploying it on OpenShift (for free)

August 5, 2015 | Data Analysis, Data Engineering

Building a Google analytics dashboard with Python3, Tornado and deploying it on OpenShift (for free)

A few weeks ago, we thought about building a Google analytics dashboard to give us easy access to certain elements of our Google Analytics web traffic. We saw some custom dashboards for bloggers, but nothing quite right for our goal, since we wanted the data on a big screen for everyone in the office to view.

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OpenCredo and Container Solutions Partner to Deliver Emerging Technologies
Traits with Java 8 Default Methods

January 30, 2015 | Software Consultancy

Traits with Java 8 Default Methods

When I first started programming in Scala a few years ago, Traits was the language feature I was most excited about. Indeed, Traits give you the ability to compose and share behaviour in a clean and reusable way. In Java, we tend deal with the same concerns by grouping crosscutting behaviour in abstract base classes that are subsequently extended every time we need to access shared behaviour in part or in total.

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Neo4j in Action

December 21, 2014 | Publications

Neo4j in Action

Neo4j in Action is a comprehensive guide to designing, implementing, and querying graph data using Neo4j. Using hands-on examples, you’ll learn to model graph domains naturally with Neo4j graph structures. The book explores the full power of native Java APIs for graph data manipulation and querying.

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November 19, 2014 | Microservices

The 7 Deadly Sins of Microservices

Undeniably, there is a growing interest in microservices as we see more organisations, big and small, evaluating and implementing this emerging approach. Despite its apparent novelty, most concepts and principles underpinning microservices are not exactly new – they are simply proven and commonsense software development practices that now need to be applied holistically and at a wider scale, rather than at the scale of a single program or machine. These principles include separation of concerns, loose coupling, scalability and fault-tolerance.

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October 23, 2014 | Cassandra

Spring Data Cassandra Overview

Spring Data Cassandra (SDC) is a community project under the Spring Data (SD) umbrella that provides convenient and familiar APIs to work with Apache Cassandra.

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Validating your test strategy

November 6, 2013 | Software Consultancy

Validating your test strategy

In many organisations, development and test teams have a ready answer for this, and that answer is usually wrong. Commonly, teams use test counts and code coverage statistics, which alone are not enough to validate a test approach and run the risk of giving a false sense of security to stakeholders. In practice, we are not able to fully prove the efficacy of our test strategy until after a release. Once software is in use, new defects highlight where our tests are failing to validate the software and where we need to invest effort to improve coverage. This is where many teams fail to learn and improve.

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Spring Integration in Action is now available
OpenCredo Partners with EsperTech to Offer Solutions for High Performance, Event-Driven Systems