Backend Programming
Why Kubernetes and Docker Are Written in Go
While developers debate the pros and cons of Python, Java, and C#, another language has become dominant in the background of the internet over the last decade: Go (Golang). Developed by Google, Go has grown into the unofficial “language of the cloud.” Virtually all essential, performance-critical cloud infrastructure tools used today—such as Docker, Kubernetes, Terraform, Prometheus, and HashiCorp Vault—are written entirely in Go. The language’s success lies in the brilliant balance it strikes: the raw execution speed and low system footprint of C or C++, combined with the read speed, simplicity, and productivity of dynamic languages like Python.
For backend software developers building microservices that require high network throughput and rely heavily on asynchronous communication, Golang offers out-of-the-box features that other languages lack or can only match after complex optimizations.
Goroutines: Concurrency Without the Pain
The absolute ‘killer feature’ of Go is the way it handles concurrency. In traditional languages like Java or C#, developers use OS threads to execute tasks in parallel. OS threads are ‘heavy’ (they easily consume 1-2 megabytes of RAM per thread), and starting and switching between threads (context switching) requires significant CPU resources. Consequently, a server freezes at a few thousand threads.
Go solves this with ‘Goroutines’. These are ‘lightweight, green threads’ that are not managed by the operating system, but by the Go Runtime itself. A Goroutine consumes only 2 kilobytes of startup memory. You start an asynchronous function in Go simply by the word go to place for the function call (e.g. go sendEmail(user)As a result, it is perfectly normal for a backend service on a simple VPS to have millions of independent Go routines open simultaneously to handle HTTP requests or WebSocket connections without the server crashing.
Communicating Sequential Processes (CSP) via Channels
When millions of asynchronous tasks run simultaneously, they must be able to securely exchange data with each other. In other languages, threads share memory and you use complex ‘Mutex Locks’ to prevent two threads from overwriting data at the same time (race conditions). The philosophy of Go is fundamentally different: “Do not communicate by sharing memory; instead, share memory by communicating.”
This is achieved by means of ‘Channels’. A channel is a secure, orchestrated ‘pipeline’ between Go routines. Go routine A dumps a task into the channel, and the Go runtime guarantees that the data is safely retrieved from the channel by Go routine B, without external locks or data corruption. This leads to a very robust architectural design (the Worker-Pool pattern) that is extremely scalable across multi-core processors.
Static Compiled: Deployment is Simple
Whereas for a Node.js or Python app you have to provision your production container with complex dependencies (such as package.json files, pip requirements, or runtime dependencies), Go excels in distribution. Go is a compiled language. The compiler takes your entire codebase and pastes it together into a single, independent, static binary executable file. You can transfer this small file (often only 15MB) to any ‘bare’ Linux server, without the Go runtime itself needing to be installed on the server. The file contains everything needed and starts up in fractions of a millisecond. For insight into competing and performance-oriented backend languages, read more in the backgrounds on Tweakers.
Next: Modern Database Design: The Battle Between NoSQL, Relational, and NewSQL (CockroachDB)
