In many backend teams, pull requests slowly grow into something nobody wants to review.
A developer starts working on a feature.
At first, it’s just a small change — maybe a new endpoint or a service update.
Soon another improvement gets added.
A small refactor follows.
Finally, a fix for something unrelated appears.
Two days later, the pull request contains 900 lines of changes across 14 files.
At that moment, something predictable happens.
The review slows down.
Not because the reviewers are lazy — but because large pull requests create cognitive overload.
And once reviews slow down, the entire development workflow begins to lose momentum.
Previous article in this category: https://codecraftdiary.com/2026/02/21/why-just-one-more-quick-fix/
The Psychological Problem of Large Pull Requests
Large pull requests create a subtle psychological effect.
When a reviewer opens a PR and sees:
+824 −217 changes
their brain immediately categorizes it as expensive work.
The result is predictable:
- The review gets postponed.
- The reviewer waits for “more time”.
- The PR sits for hours or days.
Eventually, when someone finally reviews it, they cannot realistically analyze everything in depth.
So one of two things happens:
- The reviewer skims the code and approves it quickly.
- The reviewer leaves many comments that trigger long discussion threads.
Neither outcome improves delivery speed.
Small Pull Requests Change the Dynamic
Now compare that to a PR that looks like this:
+42 −8 changes
This feels manageable.
A reviewer can realistically read the entire diff in a few minutes.
This leads to several important effects:
1. Faster Reviews
Small PRs get reviewed faster simply because they feel easier.
Many teams see review times drop from days to hours after adopting smaller pull requests.
2. Better Feedback
When the code is smaller, reviewers can focus on design decisions instead of scanning files.
Instead of writing comments like:
“This file changed a lot, can you explain the logic?”
they can ask more meaningful questions:
“Should this logic live in the service layer instead?”
3. Less Risk
Large pull requests often hide bugs.
For example, reviewers may miss subtle mistakes when hundreds of lines change at once.
Small PRs isolate changes.
If a bug appears, it’s easier to trace it back to a specific change.
A Practical Example
Consider a backend developer implementing a new feature:
Send notification emails when an order is shipped.
A typical large PR might include:
- database migration
- new notification service
- email template
- queue job
- controller changes
- unit tests
- refactoring an old helper
All combined into one big pull request.
Instead, this can be split into several smaller ones.
PR 1 – Database Migration
Add shipped_at column to orders table
Simple schema change.
PR 2 – Notification Service
Create OrderShipmentNotifier service
Pure backend logic.
PR 3 – Queue Job
Add SendShipmentEmail job
Background processing.
PR 4 – Controller Integration
Trigger notification when order is shipped
Integration step.
Each PR becomes reviewable within minutes.
The entire feature moves through the pipeline much faster.
The Hidden Benefit: Continuous Integration
Small pull requests also improve CI pipelines.
Large PRs often cause several problems:
- longer build times
- harder debugging when tests fail
- multiple unrelated failures
When a small PR fails CI, the cause is usually obvious.
Example:
PR title: Add OrderShipmentNotifier service
CI failure: NotificationServiceTest fails
The fix is straightforward.
Compare this to a massive PR with dozens of changes — the failure may come from anywhere.
Why Developers Resist Small Pull Requests
Despite the benefits, many developers hesitate to split their work.
Common reasons include:
“The feature isn’t finished yet.”
This is the most common argument.
But many PRs do not need to represent a finished feature.
They only need to represent a safe incremental step.
For example:
You can merge a service class before it’s used anywhere.
That’s perfectly valid.
“It creates too many PRs.”
This concern sounds logical but rarely holds in practice.
Ten small PRs usually move through the system faster than one large one.
Why?
Because multiple reviewers can process them quickly instead of blocking on one huge change.
“It’s extra work.”
At first, splitting work into smaller PRs requires discipline.
But after a few weeks, it becomes natural.
Developers start thinking in incremental changes rather than large feature drops.
A Simple Rule That Works
Some teams use a simple heuristic:
If a pull request takes more than 10 minutes to review, it is probably too large.
This isn’t a strict rule, but it works surprisingly well.
Another guideline:
- 200–300 lines of diff should usually be the upper limit.
Beyond that, review quality drops quickly.
The Long-Term Impact on Workflow
When teams consistently use small pull requests, several improvements appear over time.
The pipeline becomes predictable
PRs move steadily through the system instead of forming large queues.
Developers ship code more often
Frequent merges reduce integration conflicts.
Code reviews become collaborative
Instead of being a bottleneck, reviews become quick feedback loops.
And perhaps most importantly:
The team starts focusing on continuous delivery instead of large feature dumps.
Final Thought
Many teams try to improve their development workflow by introducing new tools, processes, or complex CI pipelines.
But one of the most effective improvements is surprisingly simple:
Keep pull requests small.
Small pull requests reduce friction in every stage of development:
- code review
- testing
- debugging
- merging
They allow teams to maintain momentum — and momentum is often the most valuable resource in software development.