A defer statement invokes a function just before the surrounding function returns. Multiple defers within a function are executed in reverse order of their calls, following the Last In First Out (LIFO) principle. Defer is commonly used to ensure resource cleanup, regardless of the function's success or failure. For …

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Like many developers, I often leave browser's "Developer Tools" open for websites of interests. Last week, while playing with our staging service, I saw repeated CORS errors in the Console tab and 504 Gateway Timeouts in the Network tab. It was my first time seeing these two errors together. So I decided to …

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At iheartjane, we use Go web server to serve Ad requests. After some time in production, we noticed a lot of “context canceled” error logs. The following screenshot of CloudWatch Log Insights query shows the frequency of “context canceled” errors. It left us puzzled about the underlying causes of these context cancels. …

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I’ve observed quite a few instances where engineers, including myself, have created unnecessarily complex solutions. To cultivate a better R&D organization, it is crucial to choose simplicity by default. In this blog, we’ll look at three don’ts and three do’s that help make simplicity the default. Don’t invent …

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Identifying unique entities is a frequent requirement in software development. For instance, assigning a unique ID to each Ad impression enables us to link related events for billing and analysis. However, generating unique IDs becomes challenging when dealing with large distributed systems. In this survey, we explore …

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We set up test doubles when it is difficult or impossible to use real objects due to complexity or external dependencies. In Go, an interface is a collection of method signatures that define a set of behaviors. With interfaces, it is easy to create test doubles in Go. However, should you write test doubles on your own, …

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