Imagine you're working on a really important project.
Could be anything, a huge presentation, maybe a complex
design, or you know, the code for the next big gap.
You're totally in the zone making critical changes, and
then bam, you realize you actually need to go back to how
things were last week, maybe even last month.
Oh yeah, that's sinking feeling. Exactly.
Or picture this, you're collaborating with a whole team,
all working on the very same files, and suddenly everyone's
changes are just trampling over each other.
It's it's digital chaos A. Complete mess.
It sounds like a recipe for absolute disaster, right?
Lost work, massive frustration. Definitely.
OK, let's unpack this. Today we're diving deep into
version control, and this isn't just some jargon.
It's really the core discipline that makes modern software
development and honestly, any tricky collaborative digital
work even possible and crucially, safe and efficient.
So our mission is to explore how teams manage all these digital
files, how they track every single change and work together
effectively without ending up in that chaotic mess we just talked
about. It's way more than just hitting
save. It really is that digital chaos
you painted. That's the perfect reason why
version control is just so essential now.
It's not only about code. It really is the backbone for
any collaborative digital effort.
Version control. It's not just a tool, it's
almost like the silent guardian of your project's history.
It's the engine allowing hundreds, maybe thousands of
people to work on the same thing without it all falling apart.
It makes things reliable, let you innovate faster because,
well, failures reversible. OK, so let's paint the picture.
Software development. It's almost always a team
effort, right? Almost always, yeah.
So the second you have more than one person touching the same
files, you hit that fundamental problem.
How does everyone keep track? How do you make sure your
changes don't break someone else's work?
And that's where this idea of repository comes in.
You should think of it less like a simple folder and more like a
like a secure vault or a version database for the entire project.
A central hub. Yeah, the central nervous system
maybe, where every change, every file version, all the history is
meticulously tracked. And it serves 2 really vital
purposes, obviously facilitating that teamwork, but just as
critical, making sure the operations team knows exactly
which version needs to go live, you know, into production with
certainty. And they can know that with
certainty because the version control system, the VCs, it's
essentially this robust system designed purely to track and
manage every single change made to files over time.
It performs what feels honestly almost like a magic trick.
A magic trick? How so?
What doesn't just keep the latest version, it keeps a
detailed history, like an audit trail of every version of every
file that's ever been in that project.
So developers literally get an undo button that can go back
weeks, months, even years. Wow, like a time machine for
code. Pretty much, if you need the
code as it was six months ago to debug some weird old issue, or
maybe restore a stable state after something went wrong, you
can instantly. It's incredibly powerful, and
what's fascinating here is just how fundamental this has become.
Our source material basically declares it's inconceivable in
modern software development to create any system to matter how
simple without a VCs. Inconceivable.
That's a strong word. It really tells you how deeply
baked in these systems are now. Absolutely.
But version control itself, it's not brand new tech, is it?
It actually has a pretty long history.
That's right, it goes way back. Yeah, it's origins are actually
in the early 1970s. That's when you had systems like
SCCS, the source code control system being developed for Unix.
That was a pretty big first step for managing code on shared
machines. Pioneering stuff back then.
And then things evolved. We saw CVS concurrent version
system pop up in the mid 80s. That was a decent step for basic
team collaboration, and then later Subversion or SVN as most
people know it arrived in the early 2000s and got really
popular. It was seen as simpler and more
robust than CVS. Right, SVN had a good run.
And all these early systems, they shared a similar structure,
didn't they? They were what we call
centralized systems. Exactly centralized.
They worked on that classic client server model.
So you have one single main server holding the entire
repository, the single source of truth.
All of the developers, the clients would connect directly
to that server. And when a developer finished
some work. Would they perform a commit?
That operation basically takes a snapshot of their changes at
that moment and logs it permanently on that central
server, making it visible to everyone else on the team.
OK, that makes sense. But then things changed quite a
bit. Oh yeah, Here's where it gets
really interesting. The early 2000s saw this, well
this revolution really with the rise of distributed version
control systems, DVCS systems like Bitkeeper, which has its
own interesting history, Mercurial and of course the big
one get, which came out in 2005. They just fundamentally changed
the approach. How so?
What makes them distributed? Instead of that client server
setup, DVCS uses more of a peer-to-peer architecture.
What this means, fundamentally, is that each developer has a
full, complete functional version control system, a whole
copy of the repository history, and all right there on their own
machine. Wait, everyone has the entire
repository locally? The entire thing.
Now in practice, teams usually still have a designated central
repository that everyone synchronizes with just for
coordination, but the key difference is developers
primarily work and commit changes to their local
repository first. Then they sync up with that
central 1 using a couple of main operations, pull which grabs the
latest changes from the central repo and updates their local
copy, and push which sends their own local commits up to the
central repo. That feels like a pretty major
shift in architecture if everyone's got their own full
copy locally. I mean, doesn't that add
complexity? Why make that switch?
What's better about this distributed way of doing things?
That's a fair question. It can see more complex
initially, especially compared to the straightforward central
model, and look for maybe very small Co located teams.
A centralized system might still be perfectly fine, but DVCS
really shines and the reason it took over is how well it
supports large distributed teams and especially open source
projects. The advantages once you sort of
dig in, are significant. Like what?
Well, first, because you commit locally first, you can work and
manage versions completely offline, no network connection
needed until you're ready to push or pull.
Huge flexibility boost. Right, you're not tied to the
server. Exactly.
Second, it encourages frequent commits.
You can save your work really often, even if it's just a
partial implementation or something you're experimenting
with directly to your local repo, without messing up the
main code base for everyone else.
So you can save progress without worrying about breaking the
build for the team. Precisely 3rd.
Those local commits are executed in less time.
They're just faster oerations because they're haening right
there on your machine, not over a network to a central server.
Faster feedback? Yep.
And finally, synchronization is more flexible.
You don't have to just sync with one main central repo.
You could set up hierarchies, maybe team level repos that then
sync up, or even developers pulling changes directly from
each other. Lots more workflow
possibilities. That flexibility does sound
powerful, especially for big, maybe globally distributed
projects. And I mean when you talk DVCS
today, one name just dominates the conversation.
Git. Absolutely, Git is king.
The origin story is pretty cool actually.
It was developed, as you mentioned, under the leadership
of Linus Torvalds. You know, the guy who created
Linux? That's right, the Linux
connection is key. Yeah, because apparently in the
early days the Linux kernel project used that commercial
system, Bitkeeper. But then in 2005, the company
behind Bitkeeper revoked the free licenses they've been
giving the Linux folks. That caused a bit of a crisis.
Right, so Torvalds and his team basically said OK fine, we need
our own open source system that actually works for our massive
distributed project, and they literally built git in like a
few weeks. Incredible.
An amazing feat born out of necessity now.
Git itself is primarily a command line tool, which can
sound a bit scary for some people it.
Could be intimidating, yeah. Lots of commands to learn.
But thankfully, because it's so popular, loads of really good
third party graphical interfaces have popped up, so you can use
git visually clicking buttons instead of typing commands,
which makes it way more accessible.
Definitely lowers the barrier to entry, and that popularity leads
us perfectly to GitHub. It's really important to draw
this distinction clearly. OK, GitHub is not Git.
GitHub is a code hosting service that uses the git system.
Think of it like a web platform built on top of GITS
capabilities. So git is the engine, GitHub is
the car or maybe the garage. Kind of, yeah.
GitHub provides hosting. It famously offers free public
repositories which are wise become the heart of the open
source world and also offers paid private repositories for
companies and corporate use. The analogy in our source
material is pretty good. Think about e-mail.
Instead of installing and running your own e-mail server
locally, which you could do, most companies just use a
service from a third party like Google through Gmail.
Right, you outsource the management.
Exactly. Similarly, companies can use
GitHub or competitors like GitLab or Bitbucket instead of
managing their own internal git servers.
It simplifies things. Oh.
OK, that makes total sense. So with git and platforms like
GitHub being the standard, how do organizations actually
structure their code within these systems, especially when
they have lots of projects? This brings us to a really
interesting strategic decision point, the whole multi repos
versus mono repos debate. Yes, the repo strategy question.
It's a big one. So what does this all mean?
Let's break down those terms, OK?
So multi repo is probably the approach that feels most
intuitive initially. It's simply where an
organization sets up 1 repository for each project or
system. Makes sense.
Separate projects, separate repos.
Right, if your company, let's call it My Org, has three
different software systems, you might have repos like My Org
System one, My Org System 2, My Org System 3.
Pretty straightforward. OK.
And the alternative? Monorepos.
The Monorepot. Approach is quite different.
Here you have a single repository that contains all the
organization's projects. These different projects are
then usually structured just as subdirectories inside that one
giant repository. All of them in one place, yeah.
So using our example, you just have one repo, maybe My Oracle,
the code or something. And inside that you'd find
folders for system 1, system 2, system 3, and maybe shared
libraries, tools, everything else.
And what often surprises people is that this mono repo approach,
despite sounding maybe a bit nuts, is actually often adopted
by large companies such as Google, Meta and Microsoft.
Wow, really? Google puts all its code in one
single repository? That sounds massive, potentially
incredibly unwieldy. Why would they do that?
What are the advantages of having such a gigantic single
repo? It definitely sounds
counterintuitive at first glance.
And yes, they are unimaginably massive repositories, but for
companies operating at that kind of scale, the Mono repper offers
some really compelling advantages.
OK. I'm curious.
Well, First off, with everything in one place, there's zero
ambiguity about where the latest version of any piece of code
lives. It creates a true single source
of truth for all code versions. You eliminate a whole category
of problems related to figuring out which version of which
library works with which version of which service.
Consistency. Exactly.
Huge for consistency. Second, Mono repos really
encourage code reuse and sharing.
Because all the code is right there.
It's much easier for developers to discover and use libraries or
components built by other teams. It sort of breaks down silos.
Easier collaboration across teams then. 3rd, and this is a
big one, changes across multiple projects can be atomic.
Imagine you need to fix a bug or add a feature that affects a
both system 1 and system two in a Mona repo.
You can often make the necessary changes to both systems within a
single commit. So it all goes in together or
none of it does. Precisely.
You avoid that awkward state where one system is updated but
the dependency isn't leading to things breaking.
It ensures consistency across dependent systems.
And finally, Mona repos facilitate the execution of
large scale refactorings. Like renaming something used
everywhere. Exactly.
Imagine you need to rename a core function or change an API
that's used by hundreds of different internal projects In
Mona repo. You can potentially do that
entire refactoring across the entire code base in one single
commit. That would be incredibly
difficult and coordination heavy across dozens or hundreds of
separate repositories. OK, I can see the appeal now,
especially for coordinating changes at massive scale.
That atomicity and refactoring power sound significant, but it
still sounds like it must come with its own set of challenges.
I mean, managing A repo that big?
Oh. Absolutely, you're right to push
back on that. Monterepos are definitely not a
free lunch. They come with substantial
engineering challenges. Well for starters, Mono repos
absolutely require specific tools to navigate large code
bases. Our source mentions Google had
to build custom plug insurance for their ID ES just so
developers could effectively work with their code base
without getting totally lost or bogged down.
Standard tools often just don't scale.
Right, the tooling has to keep up.
Exactly. You also need incredibly
sophisticated build systems. You can't afford to rebuild the
entire code base every time someone makes a small change.
The build system needs to be smart enough to only build the
specific things that were affected.
Performance becomes critical. Hugely critical.
You also need very fine grained access controls because you
probably don't want every single developer to have access to all
the code, especially sensitive parts.
And yeah, there can be performance hurdles just
checking out or updating such a massive repository, even with
optimized tooling. It's a significant investment in
infrastructure, tooling and processes.
So it's a solution tailored for a specific kind of scale and set
of problems, not necessarily universal best practice.
Precisely. It's a trade off.
It solves some complex coordination problems, but
introduces new challenges around tooling and scale.
It works for Google, Meta, Microsoft, but it might be
overkill or even detrimental for smaller organizations.
It's amazing really, just thinking about the sheer
complexity hidden beneath the surface of the apps and services
we use everyday, all built on these layers of version control.
So we've gone from why version control is absolutely essential,
that bedrock for collaboration and history through its
evolution from centralized systems to the distributed world
of Git. And then looked at these big
strategic choices companies face with multi repos versus those
giant mana repos, understanding the pros and cons, especially at
scale. It really hammers home that
version control isn't just a minor technical detail, it's
truly a foundational pillar supporting modern software
engineering. It's what enables the scale, the
speed, the collaboration we see today.
It lets teams build these incredibly complex things
reliably, efficiently, without getting lost in the history or
fearing mistakes. So as we wrap up this deep dive,
maybe the thought to leave you with is that version control is
fundamentally about managing change.
And in our constantly evolving digital world, that ability is
everything. It lets us build, innovate, fix
things things, and work together effectively.
So next time you save a file or collaborate on any kind of
digital project, maybe spare a thought for the hidden systems
making it all work smoothly. Thank you for joining us on this
deep dive.