How to write code with few bugs?

Summary

This video script discusses strategies for writing code with minimal bugs, emphasizing the importance of understanding automated testing, including unit, integration, and visual regression testing. It highlights the significance of the testing pyramid and the need for a comprehensive approach to software delivery, from development to production. The speaker shares real-world examples to illustrate common pitfalls and suggests using feature flagging and blue-green deployment to mitigate risks. The script concludes by advocating for simplicity in code to reduce complexity and potential bugs.

Takeaways

• 🔍 **Understand Automated Testing**: The importance of automated testing, including unit, integration, and visual regression testing, is emphasized to ensure each layer of the application works as expected.
• 📚 **Learn the Testing Pyramid**: Familiarize yourself with the testing pyramid to understand the different levels of testing and how they are applied in your specific tech stack.
• 🛠️ **Know Your Stack's Tools**: Gain knowledge of the tools commonly used in your tech stack for effective bug detection and management at various levels.
• 🦟 **Bugs are Unintended Behaviors**: Recognize that bugs are simply unintended behaviors that can affect user experience, and understanding this can help in identifying potential failure points.
• 🔗 **Environment Synchronization**: Ensure that updates across different environments are synchronized to prevent inconsistencies that can lead to production issues.
• 🚫 **Prevent Temporary Outages**: Utilize strategies like feature flagging and blue-green deployment to avoid temporary outages during updates.
• 🔄 **Continuous Learning**: Acquire a full-stack understanding to effectively manage the software delivery process and mitigate potential production issues.
• 🛡️ **Implement Fail-Safes**: Apply necessary safeguards such as health checks and redundancies to handle potential failures in production.
• 🔄 **Rollbacks and Redundancies**: Prepare for the possibility of bugs by having rollback procedures and redundancy systems in place.
• 📈 **Simplicity in Code**: Write simple and stable code to reduce complexity and the likelihood of bugs, especially in the delivery process.
• 🌐 **Consider Global Issues**: Be aware of potential issues like character encoding that can affect users globally and ensure your application is prepared for such scenarios.

Q & A

What is the primary focus of the discussion in the video script?

The primary focus of the discussion is on the best approaches to write code with very few bugs, emphasizing the importance of understanding automated testing and the testing pyramid.

Why is automated testing crucial in reducing bugs in software development?

Automated testing is crucial because it helps to ensure that each layer of the application is working as expected, thus preventing unintended behavior that affects the user experience.

What is the testing pyramid and why is it important?

The testing pyramid is a concept that illustrates the different levels of testing in software development, from unit tests at the base to UI tests and end-to-end tests at the top. It's important because it helps developers understand the general tools and patterns used to deal with bugs at different levels.

What is an example of a production issue mentioned in the script?

An example of a production issue mentioned is when a developer updated the base URL of an application without coordinating with the operations team, leading to a broken load balancer and incorrect routing, which caused the entire application to fail.

Why did the QA environment not help in the scenario described with the developer updating the base URL?

The QA environment did not help because the issue was related to the front-end routing and the developer did not consider how to synchronize the updates of the routing with the production environment, leading to a temporary outage.

What is feature flagging and how can it help in reducing bugs?

Feature flagging is a technique that allows developers to enable or disable features without deploying new code. It helps in reducing bugs by allowing for a safer deployment process, such as blue-green deployments, where a new version of the code can be tested before fully replacing the old one.

What is the significance of understanding the entire delivery process from code writing to production?

Understanding the entire delivery process is significant because it allows developers to identify potential points of failure and implement necessary fail-safes, thus reducing the likelihood of bugs in production.

What is the importance of writing simple code to minimize bugs?

Writing simple code is important because it reduces unnecessary complexity in the delivery process, making it easier to manage and less prone to introducing bugs.

Can you provide an example of a common mistake that leads to bugs, as mentioned in the script?

An example of a common mistake is when developers forget to consider the execution environment or logical errors, such as not properly importing code libraries into a Docker container, leading to a broken container build.

What strategies are suggested for dealing with bugs in production?

Strategies suggested include using feature flagging, implementing redundancies like multiple availability zones, running end-to-end tests in production, and ensuring that there are checks and health monitors for running code.

Why is it recommended to have more than one availability zone when dealing with cloud providers?

Having more than one availability zone is recommended to provide redundancy and increase the reliability of the application, ensuring that if one zone goes down, the application can still function in another zone.

Outlines

00:00

🔬 Best Practices for Writing Bug-Free Code

The speaker emphasizes the importance of automated testing as a fundamental approach to minimize bugs in software development. They introduce the concept of the testing pyramid and suggest understanding the tools and patterns specific to one's tech stack. The narrative includes a real-world example where a lack of communication between development and operations teams led to a production failure due to an untested environment. The speaker advocates for feature flagging and blue-green deployment strategies to ensure backward compatibility and prevent downtime during updates.

05:00

🛠 Understanding the Delivery Pipeline to Reduce Bugs

This paragraph delves into the complexities of the software delivery process and the potential for bugs at various stages. The speaker recounts an incident where a developer's update caused a Docker container to fail due to incorrect library paths. The importance of understanding the entire code journey from development to production is highlighted, along with the necessity of implementing fail-safes like automated testing, health checks, and feature flagging. The speaker also stresses the value of writing simple code to reduce unnecessary complexity and the potential for bugs.

10:01

📚 Comprehensive Knowledge for Minimizing Software Bugs

The final paragraph underscores the need for developers to be well-informed about the full spectrum of tools and strategies available to prevent bugs. It discusses the importance of continuous learning in areas such as site reliability engineering. The speaker provides advice on creating a robust system for checking and rectifying issues at each step of the software delivery process. They also mention the significance of keeping the code simple and having strategies in place for production environments, such as end-to-end testing and feature toggling, to ensure software reliability.

Keywords

💡Automated Testing

Automated Testing refers to the use of software to execute tests on a program or system to identify any errors or bugs. In the video, it is emphasized as a fundamental practice in reducing bugs, including unit testing and integration testing. The script mentions the importance of understanding the testing pyramid and using appropriate tools for different levels of testing to ensure each layer of the application is functioning as expected.

💡Testing Pyramid

The Testing Pyramid is a concept in software testing that illustrates the different levels of tests and their recommended proportions. It typically consists of a large base of unit tests, a middle layer of integration tests, and a smaller top layer for UI tests. The video script discusses the pyramid to highlight the importance of having a balanced approach to testing at various levels to catch bugs early in the development process.

💡Unit Testing

Unit Testing is a method where individual components or units of a software are tested to determine if they are fit for use. The script mentions unit testing as the first step in the testing process, ensuring that the code written does not have logical errors and functions correctly in isolation.

💡Integration Testing

Integration Testing is the phase where individual units are combined and tested as a group to evaluate their interactions. The video script uses this term to explain the importance of ensuring that when components work together, they perform as expected, which is crucial for catching bugs that may not be evident in unit tests.

💡Visual Regression Testing

Visual Regression Testing involves comparing the visual representation of a user interface over time to detect unintended changes. The script briefly touches on this as a type of testing that can be important, especially for UI changes, to ensure that updates do not negatively impact the user experience.

💡Feature Flagging

Feature Flagging is a technique used to toggle features on or off in a software application without deploying new code. The video script discusses feature flagging as a strategy to safely deploy new features, allowing developers to test and roll out changes gradually and control the feature release process.

💡Blue-Green Deployment

Blue-Green Deployment is a strategy that reduces downtime and risk by running two identical production environments, one active (blue) and one idle (green). The video script uses this term to illustrate a method of deployment that allows for zero-downtime updates and easy rollback if something goes wrong with the new version.

💡Backwards Compatibility

Backwards Compatibility ensures that new versions of a product can still function with older versions or components. In the script, it is mentioned in the context of making sure that updates do not break existing functionality, which is essential for maintaining stability when introducing new features or changes.

💡Code Simplicity

Code Simplicity advocates for writing code that is easy to understand, maintain, and less prone to errors. The video script emphasizes the importance of simplicity in code design to reduce complexity and the potential for bugs, suggesting that simpler code is easier to manage and test.

💡Environment Consistency

Environment Consistency refers to the practice of keeping development, testing, and production environments as similar as possible to avoid discrepancies that can lead to unexpected behavior in production. The script uses the example of a developer who did not consider the production environment's specific conditions, leading to a failed update.

💡SRE (Site Reliability Engineering)

Site Reliability Engineering (SRE) is an engineering discipline that incorporates aspects of software engineering and practices from reliability engineering to maintain large-scale, distributed systems. The video script mentions SRE to highlight the specialized knowledge required to master the various aspects of software delivery and ensure reliability, including understanding how to prevent and handle bugs in production.

Highlights

The importance of understanding automated testing, including unit testing and integration testing, to reduce bugs.

The significance of the testing pyramid and its role in identifying the right tools for different testing levels.

The necessity for developers to comprehend the layers of the application that can fail and how to assert each layer's functionality.

The example of a production issue caused by an update to the base URL not being checked with the operations team.

The concept of feature flagging and blue-green deployment as a safeguard against production issues.

The importance of understanding the entire delivery process from code writing to production to identify potential failure points.

The example of a Docker container issue due to a path problem with code libraries not being imported correctly.

The necessity for developers to consider the execution environment and potential logical errors in their code.

The role of health checks in identifying outages in production and the importance of fail-safes.

The recommendation to have more than one availability zone for redundancy, especially when dealing with cloud providers.

The strategy of using feature flagging, rollbacks, and redundancies to mitigate production issues.

The emphasis on writing simple code to reduce unnecessary complexity and potential bugs.

The example of encoding format issues leading to broken text for non-UTF characters in a database.

The need for a comprehensive understanding of the software delivery process and its components to prevent bugs.

The importance of having a gateway system to check the functionality at each step of the delivery process.

The role of unit testing in ensuring the logical correctness of newly written code.

The value of automated testing before production deployment to catch issues like container failures early.

The strategies for ensuring code works correctly in production, including end-to-end testing and feature flagging.

Transcripts

hey guys so today you and I are going to

talk about

very few bugs so let's get into it so

the question in question was hi

Frederick what are the best approaches

to write code with very few bugs

well uh there are a few tried and true

patterns for how to do this

and I'll I'll try to basically give you

sort of those tips and tricks that I

usually use in order to try to reduce it

down to the bare minimum that I can can

sustain

so first and foremost you need to

understand automated testing hopefully

that is no-brainer for those of you who

have been doing some professional work

basically that means unit testing and

Trend testing if you have a UI of some

sort of visual regression testing

etc etc there are many patterns for how

to do this but in essence it's good for

you to take a look at the testing

pyramid and have an understanding of

what every stack you're using what is

the general way that people use like

what are the general tools that your

specific stack leverages in order to

deal at with the bugs at different

levels because this is a very important

factor a bug is unintained it's just

unintended Behavior at some part of the

application that somehow affects the

user experience the reason why I say

that it might sound obvious but it's

actually very important is that you have

to understand as a software developer

what layers of the application can fail

and how do you assert that each

individual layer is working as expected

this is very complicated

and the reason I can give you an example

so I was working with a developer of

mine

a few a while back we I asked this this

person was updating making an update to

the

base URL of of an application

and so in the code review he had written

unit tests like he had made sure that he

had tested everything you know in like

properly all the like end-to-end tests

had been passing and Etc so basically

the whole suite and he

had done quote unquote all the things

that on a normal story he was expected

to do

and then he pushes like he merges this

code sends it out into production boom

production issue immediately

uh the reason being why that in what it

had why what happens is that the update

that he had made had not been checked

with the operations team which meant

that the load balancer that he was

basically in back behind that forwards

all the requests was not updated and

also so the routing wasn't happening

correctly which meant the whole

application broke because there was an

environment which in which he had not

been attested before he released which

was the production environment

now I talked to him about this and I he

said oh well because in this case

scenario he he said yeah it would have

been great if we had a QA environment or

a test environment before we pushed this

thing so I could have tested it in that

environment and I went that wouldn't

have helped you

because the real this was in this case

it was a front-end Rover because and I

said the reason why I wouldn't have

helped you was because when you have

pushed would you would have pushed it to

the QA environment

yes very likely you would have seen a

breakage and you would have seen that

you needed to update the routing of this

thing

but the question is would you have known

how to

do that for production as well you might

have known that you needed to make the

update for production as well but how

would you do it in this manner because

in this specific manner like there was

no way to synchronize the updates of the

routing at the same time as pushing into

production in other words there's a

window where something is inconsistent

either the routing is not going to work

or the application is not going to be

updated so something's going to be

broken for a little window of time in in

theory basically and so what he and I

started talking about was that okay so

how do you Safeguard yourself from not

making a mistake like this and I said

well it's very simple you have to

understand how to in this case the like

I can give you the short answer feature

flagging basically where you need to be

able to do a blue green type of

deployment thing where you need to be

able to

spin up a new version of the code like

basically a backwards compatibility

make sure that all the traffic hits the

new application and then degrade the old

one because if you don't do that you're

basically in a situation where as I said

you have temporary outage

and maybe that's fine and in the

scenario it wasn't a big deal but that's

the sort of thinking that you need to

have when you're trying to figure out

how to reduce the amount of bugs you

have because the the bugs that guys

bikes can happen in so so so many ways

and so it's really important for you to

have an understanding of the impacts

like like all the parts that make up

everything from how you get the code

from your laptop all the way into the

production environment and when it's

actually running in production this

takes years

and it's a full stack knowledge level

that is required to do this effectively

to to really do it effectively I had

another co-worker the other day who made

a update to the source code

was very happy with it had written unit

tests etc etc and then he pushed it and

luckily for us we had automated testing

that in this case it was a Docker

container everything was running in so

the docker container was trying to be

run and this is where you want to have

something like automated testing before

things go out into production which is

in this case it was so the container was

trying to be built and then it's frozen

error because the change that he had

made was only the bug only existed

basically here in a routing problem not

a routing problem he had a path problem

to certain libraries code libraries that

he was depending on those code libraries

were not being imported into the

Container correctly so now the container

broke

and when he made the change

he didn't think about that because he

didn't think about the next step okay

what happens when this thing goes into

the next container now this is the main

reason why bugs happen guys the

developers are forgetting about some

execution environment or like there

might be a logical error Etc so there's

tons of ways for this to happen but for

you to understand how the testing

Pyramid has to work

you have to also understand all the

things that are going to happen between

you wrote the code in your on your

workstation all the way until it's out

in production and what can possibly go

wrong when it is in production and apply

the necessary fail safes in order to

deal with that problem so as I said unit

test that's what the junior learns

that's the first step just to make sure

that the thing that you just wrote

doesn't like logically break somehow

then the next thing is integration test

you need to be able to connect to

systems or something like that to make

sure that the system still works then

you might have health checks because

something might you know if something's

running in production you don't know

maybe something there's an outage

somewhere and some service Goes Down And

if you don't know about it well then

it's down and your system is now you

know there's a bug there's a temporary

outage etc etc and then you have

questions about okay so if now something

breaks into production how do you

actually go back from that how do you

save yourself from that that's for

feature flagging for example can be in

all alternative you can have multiple

redundancies with like this is one of

the reasons why we recommend usually to

have more than one

you know availability zone or something

like that if you're dealing with Cloud

providers etc etc there's tons and tons

and tons of weight everything from

rollbacks to redundancies to Future

flagging to like backwards compatibility

uh like graceful degradation etc etc and

in order for you to write a few bugs as

as possible you basically need to know

as I said how does the entire delivery

look like what can go wrong in

production and what are the remedies

that you can apply in order to mitigate

those sorts of problems and I'll give

you one more which is a very important

one make sure that the code that you are

writing is simple

the reason why I say that it might sound

simply and like obvious but the reason

why I say that is because the simpler

you can design the code

the less likely you are to create

unnecessary complexity around the

delivery process if you have the option

of picking something that is very simple

very stable something that like where

you're basically just trying to keep

down the complexity of what you're doing

that's always almost always a good

investment for you because a lot of

these like the more complex as I was

saying with these two examples the more

complicated your environment is the more

of things you have to keep in mind

whenever you're doing the coding because

as you can imagine it's almost

impossible for you to sit there and go

yeah I wrote I changed an example would

be I changed the uh symbols here like I

I added a few classic one is a German

signs so like something like a German

characters or Chinese characters or

something like that here in this little

text here that's going to be translated

I wonder if we have the right game for

the encoding format in our database

which is another one that I've found as

well like we've I've been working on

projects where literally they have the

wrong encoding format they store things

in the incorrect format and send it back

to us so all we get is this little like

you know the placeholder

symbol for all of the non-utf I don't

remember which encoding they were using

but basically it was okay we had to show

broken text to all of our customers from

Germany etc etc because they had not

considered that this would have been a

problem so what I want you to take away

from this is that the way that you write

as few bugs as possible is number one

you have to get yourself informed of the

main testing tools you usually use the

common ones or you know unit testing and

then testing visual regression testing

feature flagging things like that but

there's more to it because it's a minute

guys it's a whole education to learn all

this sort of stuff this is sort of what

the site reliability engineers and

things like you know there's there's an

entire job to master all of this stuff

right but that is basically what it

comes down to because what you have to

understand is that there is

no like like the entire way from your

laptop all the way up

to how something is running in

production can break

and the best way for you to reduce the

amount of bugs is for you to create a

Gateway system where you know that you

have a proven way to determine at each

step of the delivery process

if something is working if it's working

correctly and some way to rectify the

problem if something did not

function correctly so as I was saying in

production environments you have a few

strategies at the code level you have a

few strategies and there's tons of this

stuff but basically try to keep things

as simple as possible and then inform

yourself about all right how do I make

sure that all quote unquote things that

can go wrong with my code have been

accounted for and that there is some way

for me to check if that thing is

actually working

unit test is a good start making sure

that you know your containers and your

production bills are working correctly

making sure that you have some type of

way of checking the running code before

it goes on into production is a good

investment making sure that as I said

visual regression testing or end-to-end

testing like features are working even

in like a QA environment doesn't have to

be a queue environment and then when

things are in production make sure that

things are working in production there's

tons of different ways of doing that

everything from running end to end

testing production to you know pinging

things or you know doing feature

flagging and turning features on and off

etc etc there's a whole like there's so

much content related to this guys so the

I suggest that you have a look but keep

that fundamental thing with you the most

important thing is that you understand

how your software it goes from your

laptop all the way out into production

and all the things that are happening as

part of that process because then you

know what all the components are and how

they in their unique way can fail you

have a great day