Product Perfect

Go, also known as Golang, is a statically typed, compiled programming language developed by Google engineers Robert Griesemer, Rob Pike, and Ken Thompson in 2007. It was publicly announced in 2009 and is designed for efficiency and ease of use with features such as garbage collection and support for concurrent programming. Noted for its simplicity and speed, Go has been used to develop some of the most popular software like Docker and Kubernetes. The language's standard library provides robust support for a variety of functionalities including web server development. Go's open-source nature allows developers worldwide to contribute to its growth and evolution.

Ask the right questions secure the right Go talent among an increasingly shrinking pool of talent.

First 20 minutes

General Go app knowledge and experience

The first 20 minutes of the interview should seek to understand the candidate's general background in Go application development, including their experience with various programming languages, databases, and their approach to designing scalable and maintainable systems.

How would you install Go on your local machine?

You can download the binary release suitable for your system from the official Go website. After downloading, you can extract the archive and set the environment variables like GOROOT, GOPATH, and PATH.

What are the basic types in Go?

Go has several types including bool, string, int, int8, int16, int32, int64, uint, uint8, uint16, uint32, uint64, uintptr, byte, rune, float32, float64, complex64, complex128.

How would you declare variables in Go?

Variables in Go can be declared using the 'var' keyword. For example: var x int. You can also declare and initialize a variable at the same time, for example: var x int = 10. If the variable is inside a function, you can use the short assignment statement := for declaring and initializing.

What is the zero value in Go and how does it work?

The zero value is the default value for a variable declared without an explicit initial value. For example, the zero value for numerical types is 0, for booleans it's false, and for strings it's an empty string.

How would you use pointers in Go?

Pointers in Go are used to hold the memory address of a value. The type *T is a pointer to a T value. The zero value of a pointer is nil. We use the & operator to generate a pointer to its operand and the * operator to denote the pointer's underlying value.

The hiring guide has been successfully sent to your email address.

Oops! Something went wrong while submitting the form.

What you’re looking for early on

Has the candidate demonstrated a strong understanding of Go language?

Does the candidate have experience with Go frameworks and libraries?

Can the candidate effectively solve problems using Go?

Does the candidate show an understanding of concurrent programming?

Next 20 minutes

Specific Go development questions

The next 20 minutes of the interview should focus on the candidate's expertise with specific backend frameworks, their understanding of RESTful APIs, and their experience in handling data storage and retrieval efficiently.

Describe the difference between array and slices in Go.

Arrays have a fixed size while slices are dynamically sized. Slices, in fact, are more common in Go than traditional arrays. Slices are built on top of arrays and provide more power, flexibility, and convenience compared to arrays.

What are structs in Go and how would you use them?

Structs are a way to group together variables of different types. They're useful when you want to create types that contain several pieces of related information. You can declare a struct using the type and struct keywords, and access its fields using dot notation.

How would you handle errors in Go?

Go uses a special built-in error type to handle errors. A function that might return an error has it as its last return value. If the error is nil, no error happened. Otherwise, the error contains a description of what went wrong. This approach makes it easy to see which functions return errors and to handle them using the same language constructs employed for any other, non-error tasks.

What are goroutines in Go?

Goroutines are functions or methods that run concurrently with other functions or methods. Goroutines are lightweight threads managed by the Go runtime. You can start a goroutine simply by adding the keyword go before a function call.

How would you use channels in Go?

Channels are the pipes that connect concurrent goroutines. You can send values into channels from one goroutine and receive those values into another goroutine. Create a new channel with make(chan val-type). Channels are typed by the values they convey.

The hiring guide has been successfully sent to your email address.

Oops! Something went wrong while submitting the form.

At this point, a skilled Go engineer should demonstrate strong problem-solving abilities, proficiency in Go programming language, and knowledge of software development methodologies. Red flags include lack of hands-on experience, inability to articulate complex concepts, or unfamiliarity with standard coding practices.

Digging deeper

Code questions

These will help you see the candidate's real-world development capabilities with Go.

What does the following Go code do?
package main

import "fmt"

func main() {
	fmt.Println("Hello, World!")
}
This code prints the string 'Hello, World!' to the console.
What will be the output of the following Go code?
package main

import "fmt"

func main() {
	var a int = 10
	var b int = 20
	fmt.Println(a + b)
}
The output will be '30'. The code adds the values of variables 'a' and 'b' and prints the result.
What does the following Go code do?
package main

import "fmt"

func main() {
	arr := []int{1, 2, 3, 4, 5}
	for _, v := range arr {
		fmt.Println(v)
	}
}
This code prints each element of the array 'arr'. It uses the range keyword to iterate over the array.
What does the following Go code do?
package main

import (
	"fmt"
	"sync"
)

var wg sync.WaitGroup

func worker() {
	fmt.Println("Worker function executed")
	wg.Done()
}

func main() {
	wg.Add(1)
	go worker()
	wg.Wait()
}
This code creates a new goroutine and waits for it to finish execution. It uses a WaitGroup from the 'sync' package to block the main function until all goroutines have finished executing.

Wrap-up questions

Final candidate for Go Developer role questions

The final few questions should evaluate the candidate's teamwork, communication, and problem-solving skills. Additionally, assess their knowledge of microservices architecture, serverless computing, and how they handle Go application deployments. Inquire about their experience in handling system failures and their approach to debugging and troubleshooting.

Describe the difference between buffered and unbuffered channels in Go.

Unbuffered channels block the sender until the receiver has received the value, while buffered channels only block the sender when the buffer is full. Similarly, they block the receiver when the buffer is empty.

What is a select statement in Go and how would you use it?

The select statement is used to choose from multiple send/receive channel operations. It blocks until one of its cases can run, then it executes that case. If multiple cases are ready it chooses one at random. This is useful when you want to wait for data from multiple channels.

How would you test your Go code?

Go has a built-in testing tool called 'go test'. You can write test functions alongside your code in *_test.go files. These functions should start with the word Test and take one argument, a pointer to the testing.T context. If the test fails, call t.Error or t.Fail.

Go application related

Product Perfect's Go development capabilities

Beyond hiring for your Go engineering team, you may be in the market for additional help. Product Perfect provides seasoned expertise in Go projects, and can engage in multiple capacities.

Go Consultive assessments

Go Application Conversion Assessment Go Application Integration Assessment Go Data & Database Integration Assessment

Custom Go development projects

Custom Go App Conversion Go Custom App Development Process App UI Design for Go Facelifts

Hiring guide for Go Engineers

Go Developer Hiring Guide

What you’re looking for early on

The ideal back-end app developer

What you’re looking to see on the Go engineer at this point.

Go Consultive assessments

Custom Go development projects