Auto-Scaling on Alibaba Cloud

When you deploy your application on compute instances on-premise or in the cloud, you have to make an educated guess about the utilisation of the resources you provision. If you have an older version of the same application running with proper monitoring, you can base your guesstimate on the current usage of compute nodes. But when this is the first time your application goes to production you are out of luck. How many users will you have each day? What will users do when they start your application and how are usage peaks distributed? Do you expect growth in the number of users? How about long term? If you have answers to all of these questions, you might be well-equipped to go with your gut-feeling and just deploy the application on the number of nodes you came up with. Let’s assume you don’t have all the answers though (which is probably the case). This is where auto-scaling comes in.

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Pub-Sub messaging with AWS SNS and SQS

When setting up a new application or platform, one of the most important things that you will need is messaging. As every part of the platform has a certain need for data, either realtime or after the fact, messages from other services within the application boundary need to be processed as efficiently as possible. This inter-executable messaging can go from simple notifications about something that happened in a domain (‘customer X changed his name to Y’) to a queue of outstanding jobs that are to be executed by workers. In any architectural case, be it (distributed) monolith, microliths, microservices or anything in between, messages will be there.

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Speech Recognition and Synthesis in the Browser

With the recent upsurge of Siri, Google Assistant and Amazon’s Alexa, speech recognition and synthesis have become an increasingly important tool in the developer’s toolbox. Working with speech data can not only improve the accessibility of your application. It can also increase conversion in your webshop, especially when customers shop on their mobile phones. Native apps have a large advantage in this space, as Apple’s SiriKit and Google’s Assistant SDK can get you up and running in a few minutes to hours.

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No WeChat no life (part III): implementing an echo service

In this three-part series on WeChat, Léon will show you how the Chinese alternative to WhatsApp’ is transforming the on- and offline lives of Chinese consumers, thereby forcing companies to reconsider their marketing and sales strategies. In the previous two parts, he argued for the necessity of a presence on WeChat for companies facing Chinese customers and gave an overview of the features. In this part, he will show you how to build a simple echo service using the WeChat APIs.

After the previous two more theoretical posts, it is time to get our hands dirty. As you might recall from part 2 of this series, companies can register an official account (OA) on WeChat to get access to all the APIs that the platform provides. An OA shows up in a user’s chat list, either between the regular chats or in a dedicated folder, and can send and receive messages to users or provide other useful on-demand services in the chat. Today, we will build an endpoint that follows the WeChat standards and can be tested on WeChat using the debug sandbox. It will echo any message a user sends by replying with the contents of the message reversed. Although this is not a really compelling example, it sets you up with the right tools to build more enticing user experiences on WeChat (and it forces you to register a WeChat account ;)). 

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