{"id":12085,"date":"2020-11-12T09:00:15","date_gmt":"2020-11-12T08:00:15","guid":{"rendered":"https:\/\/www.codemotion.com\/magazine\/?p=12085"},"modified":"2022-01-05T20:06:12","modified_gmt":"2022-01-05T19:06:12","slug":"casavo-incremental-microservices","status":"publish","type":"post","link":"https:\/\/www.codemotion.com\/magazine\/microservices\/casavo-incremental-microservices\/","title":{"rendered":"Build Incremental Architecture Through Microservices with Modern Languages – Casavo\u2019s Case Study"},"content":{"rendered":"\t\t\t\t
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\n\t\t\t\t\t\t\tTable Of Contents\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t
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  1. Reasons for change: towards microservices<\/a>
  2. Elixir and DDD, the double divine strength<\/a>
  3. Stress and success of microservices<\/a>
  4. Casavo\u2019s custom microservices: EventStore, Pond, Carol, Worms<\/a>
  5. Casavo and Elixir, a perfect marriage<\/a>
  6. Casavo\u2019s Technology Radar<\/a>
  7. Doing business with company values and life principles<\/a>
  8. Constant training: a developer\u2019s career grows with technical knowledge<\/a>
  9. Quality management and fast delivery<\/a>
  10. Casavo\u2019s Career Ladder<\/a><\/ol>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\n\n\n

    Casavo<\/strong> began as a real-estate instant buyer and has already leveraged the traction gained through this service to become a technological leader in the real estate sphere, building a tech-offer for all actors involved in a real estate transaction. The company\u2019s ambition is to become a technological reference point in the real estate world, offering many vertical solutions beyond the Instant Buyer function (especially around the microservices world).<\/p>\n\n\n\n

    \u201cMoving house is one of life\u2019s most overwhelming events, often causing months of stress and uncertainty\u201d, Casavo\u2019s CTO<\/a> Francesco Dominidiato explains. \u201cWe started Casavo in late 2017 with a mission to simplify home buying and selling. Since then, we have executed nearly 1,000 transactions for homeowners who have bought and sold homes with Casavo\u201d.<\/p>\n\n\n\n

    An Instant Buyer is an operator who uses large amounts of data and technological tools to drastically reduce the time required to sell a property. Instant Buyer directly submits purchase offers for a property, revolutionizing the traditional buy\/sell process by introducing a simpler, faster and often more convenient paradigm.<\/p>\n\n\n\n

    \u201cCasavo offers the freedom to move whenever you want, on your own terms. If you\u2019re selling, it can help you to sell your property at a competitive price in just thirty days, eliminating the hassle of showings and the months of uncertainty. <\/p>\n\n\n\n

    If you\u2019re buying, Casavo makes it incredibly easy to find and purchase the perfect home. Wherever you are in your home-ownership journey, a dedicated Casavo expert will guide you every step of the way\u201d.<\/p>\n\n\n\n

    Casavo has a clear vision to simplify the real estate buying process<\/span>. Let\u2019s see how this is achieved with respect to the company\u2019s values and stakeholders, customers included.<\/p>\n\n\n\n

    Reasons for change: towards microservices<\/h2>\n\n\n\n

    Casavo\u2019s platform was essentially born in PHP<\/span><\/strong>, with an architecture<\/span> fully based on this programming language<\/span>. This proved to be a good solution, and it\u2019s no secret that many companies develop their business in PHP<\/span>.<\/p>\n\n\n\n

    However, Casavo also wanted to \u201crefresh\u201d its core architecture. Moving towards a microservices architecture was a natural choice for these new advances, and the team decided to opt for different modern programming languages<\/span>, among which is the focus of this article – Elixir<\/span><\/strong>. <\/p>\n\n\n\n

    At the end of 2019, the company started redesigning its technological stack, with one major constraint – changes must be incremental<\/strong>. The information system can never be restarted from scratch in this business. We\u2019ll return to this particular aspect of the development process<\/span> later.<\/p>\n\n\n\n

    The differences between PHP<\/span> and Elixir can\u2019t be detailed in just a few words, but some points can be outlined in brief; in PHP<\/span>, every request generates a void process<\/span> to be managed through a simple request\/response model.  Elixir, on the other hand, is based on its own runtime – this software component<\/span> and some services stay active forever. This approach pushes performances to the top and offers a memory of past executions.<\/p>\n\n\n\n

    Elixir and DDD, the double divine strength<\/h2>\n\n\n\n

    There is a need for a more modern and agile approach to software development<\/span>, in order to speed up progress towards a given goal. <\/p>\n\n\n\n

    Why Elixir?<\/h3>\n\n\n\n

    Elixir<\/span> offers an honest and manageable technological ramp. Its adoption is not a free process<\/span>, but it can be managed step by step, a little at a time.<\/p>\n\n\n\n

    For those who are not familiar with this language, it all started with Erlang<\/span><\/strong>, a language developed by Ericsson<\/span>\u2019s engineers back in the mid-80s to manage highly concurrent telecommunication systems with extremely high reliability. <\/p>\n\n\n\n

    Erlang<\/span> achieved concurrency without hassle. Elixir<\/span> was born from Erlang<\/span> in 2012, adding a more familiar development environment<\/span> to Erlang<\/span>, among many other things.<\/p>\n\n\n\n

    If used for writing sequential code<\/span> in a single process<\/span>, the language itself is simple and the generated code is easily readable. This makes it perfect for those who are taking their first steps in learning how to use it.<\/p>\n\n\n\n

    Multiple processes<\/span> can be coordinated with Elixir<\/span>, but this is a more complex task, to be mastered further down the track.<\/p>\n\n\n\n

    \u201cElixir is flexible<\/strong>: a project, even an elaborate one, is rarely difficult to achieve easily. Honestly, it takes time to fully master Elixir, but each step to the top is nonetheless productive.\u201d<\/p>Francesco Dominidiato, CTO at Casavo<\/cite><\/blockquote>\n\n\n\n

    Stress and success of microservices<\/h2>\n\n\n\n

    “Elixir<\/span> has been accepted by Casavo\u2019s developers<\/span> with great enthusiasm and productivity<\/strong>, said Dominidiato. \u201cIn just a few months, four services have been deployed, with a fifth service at the end of the pipeline as we speak\u201d (July 2020). <\/p>\n\n\n\n

    All the services developed in this time, once deployed, worked immediately. To our utmost amazement, moreover, they did not require further adaptations in the subsequent months.\u201d<\/p>\n\n\n\n

    This success was underlined by the particular stress conditions to which the system<\/span> was subjected. One event in particular suddenly increased website visits and therefore requests for new microservices<\/span>: an advertising campaign on a satellite television channel.<\/p>\n\n\n\n

    As soon as these services were deployed, the company purchased advertising space on the Sky TV chain. That promotion dramatically increased the number of contacts with the site, putting stress on both old and new services, which were fully capable of scaling up without any problems.<\/p>\n\n\n\n

    “But is it still up?” was the frequent, astonished question of all the developers<\/span> involved in the creation of each service.<\/p>\n\n\n\n

    Casavo\u2019s custom microservices: EventStore, Pond, Carol, Worms<\/h2>\n\n\n\n

    Let’s now look at the main characteristics of each of the developed services. Each microservice<\/span>, in particular:<\/p>\n\n\n\n