Charles Fonseca
@barddoo.bsky.social
Software Engineer. Follower of Jesus.
Married to the prettiest woman.
Making databases in my spare time and occasionally writing about it.
Substack: https://charlesfonseca.substack.com/
Married to the prettiest woman.
Making databases in my spare time and occasionally writing about it.
Substack: https://charlesfonseca.substack.com/
Finally reached Redis.
open.substack.com/pub/charlesf...
open.substack.com/pub/charlesf...
Building a Redis Clone in Zig—Part 4
Benchmarking a Redis Clone: 95% Performance in Zig
open.substack.com
November 12, 2025 at 5:31 PM
Finally reached Redis.
open.substack.com/pub/charlesf...
open.substack.com/pub/charlesf...
Async/Await is finally back in Zig
open.substack.com/pub/charlesf...
open.substack.com/pub/charlesf...
Async/Await is finally back in Zig
What changed, why it matters, and how to use the new API.
open.substack.com
November 1, 2025 at 2:15 PM
Async/Await is finally back in Zig
open.substack.com/pub/charlesf...
open.substack.com/pub/charlesf...
Azure is down. Great time to be alive.
October 29, 2025 at 4:21 PM
Azure is down. Great time to be alive.
Why is there a software craftsmanship movement? What motivated it? What drives it now? One thing; and one thing only.
We are tired of writing crap.
- Robert C. Martin
Tired of writing crap?
open.substack.com/pub/charlesf...
We are tired of writing crap.
- Robert C. Martin
Tired of writing crap?
open.substack.com/pub/charlesf...
Building a Redis Clone in Zig—Part 3
Implementing RDB Persistence Using Zig's New IO Interface
open.substack.com
October 24, 2025 at 9:57 PM
Why is there a software craftsmanship movement? What motivated it? What drives it now? One thing; and one thing only.
We are tired of writing crap.
- Robert C. Martin
Tired of writing crap?
open.substack.com/pub/charlesf...
We are tired of writing crap.
- Robert C. Martin
Tired of writing crap?
open.substack.com/pub/charlesf...
New newsletter drop 📬
Interested in systems programming? Check out the newest post.
Spoiler: You won’t beat the standard library.
#ZigLang #SystemsProgramming #Redis #PerformanceEngineering
charlesfonseca.substack.com/p/building-a...
Interested in systems programming? Check out the newest post.
Spoiler: You won’t beat the standard library.
#ZigLang #SystemsProgramming #Redis #PerformanceEngineering
charlesfonseca.substack.com/p/building-a...
Building a Redis Clone in Zig—Part 2
Customizing the Hash Table for Caching Workload
charlesfonseca.substack.com
October 24, 2025 at 9:49 PM
New newsletter drop 📬
Interested in systems programming? Check out the newest post.
Spoiler: You won’t beat the standard library.
#ZigLang #SystemsProgramming #Redis #PerformanceEngineering
charlesfonseca.substack.com/p/building-a...
Interested in systems programming? Check out the newest post.
Spoiler: You won’t beat the standard library.
#ZigLang #SystemsProgramming #Redis #PerformanceEngineering
charlesfonseca.substack.com/p/building-a...
I started a Substack newsletter focused on deep dives into programming and complex technical problems. This post series will focus on the technical difficulties and development path of Zedis, my Redis clone in Zig.
Please check it out!
#Zig
charlesfonseca.substack.com/p/building-a...
Please check it out!
#Zig
charlesfonseca.substack.com/p/building-a...
Building a Redis Clone in Zig—Part 1
Lessons on Performance Optimizations in a Systems Programming Language
charlesfonseca.substack.com
October 23, 2025 at 8:16 PM
I started a Substack newsletter focused on deep dives into programming and complex technical problems. This post series will focus on the technical difficulties and development path of Zedis, my Redis clone in Zig.
Please check it out!
#Zig
charlesfonseca.substack.com/p/building-a...
Please check it out!
#Zig
charlesfonseca.substack.com/p/building-a...
“Simplicity is the ultimate sophistication,” they say. It's incredibly challenging to make systems simple. When it comes to the Cloud and everything else big tech is throwing at us, it's easy to get lost in the shuffle.
#CloudComputing #SystemDesign #DevOps
www.youtube.com/watch?v=jFrG...
#CloudComputing #SystemDesign #DevOps
www.youtube.com/watch?v=jFrG...
The cloud is over-engineered and overpriced (no music)
I tried the music and the feedback is clear enough that I think it's worth uploading a version of this with no music. I'm still learning!
I'm sorry :( I really liked the riff I wrote for the intro…
www.youtube.com
October 21, 2025 at 10:16 PM
“Simplicity is the ultimate sophistication,” they say. It's incredibly challenging to make systems simple. When it comes to the Cloud and everything else big tech is throwing at us, it's easy to get lost in the shuffle.
#CloudComputing #SystemDesign #DevOps
www.youtube.com/watch?v=jFrG...
#CloudComputing #SystemDesign #DevOps
www.youtube.com/watch?v=jFrG...
Why is there a software craftsmanship movement? What motivated it? What drives it now? One thing; and one thing only.
We are tired of writing crap.
— Robert C. Martin
We are tired of writing crap.
— Robert C. Martin
October 21, 2025 at 3:45 PM
Why is there a software craftsmanship movement? What motivated it? What drives it now? One thing; and one thing only.
We are tired of writing crap.
— Robert C. Martin
We are tired of writing crap.
— Robert C. Martin
On the AWS outage, DDH was right.
world.hey.com/dhh/we-have-...
world.hey.com/dhh/we-have-...
We have left the cloud
Since it took us years to get into the cloud in the first place, I originally imagined it would take us years to get out as well. But all that work to containerize our applications and prepare them fo...
world.hey.com
October 20, 2025 at 6:13 PM
On the AWS outage, DDH was right.
world.hey.com/dhh/we-have-...
world.hey.com/dhh/we-have-...
Learning systems programming has been both difficult and awesome.
The intriguing thing about beginning with Zig when learning low-level programming is that, despite my repeated attempts, I am completely unable to get C. In contrast, Zig feels so natural.
The intriguing thing about beginning with Zig when learning low-level programming is that, despite my repeated attempts, I am completely unable to get C. In contrast, Zig feels so natural.
October 18, 2025 at 11:30 AM
Learning systems programming has been both difficult and awesome.
The intriguing thing about beginning with Zig when learning low-level programming is that, despite my repeated attempts, I am completely unable to get C. In contrast, Zig feels so natural.
The intriguing thing about beginning with Zig when learning low-level programming is that, despite my repeated attempts, I am completely unable to get C. In contrast, Zig feels so natural.
This talk blew my mind! Joran goes through how important it is to design not only algorithms but also system interfaces for performance
I've begun to re-evaluate every system I work on, reconsidering how interface choices impact overall efficiency
#SystemsProgramming
www.youtube.com/watch?v=yKgf...
I've begun to re-evaluate every system I work on, reconsidering how interface choices impact overall efficiency
#SystemsProgramming
www.youtube.com/watch?v=yKgf...
1000x: The Power of an Interface for Performance by Joran Dirk Greef
As systems programmers, we tend to think of performance as all the low-level techniques we can and should apply in the implementation of a system.
For example, static memory allocation, amortization,…
www.youtube.com
October 17, 2025 at 3:03 PM
This talk blew my mind! Joran goes through how important it is to design not only algorithms but also system interfaces for performance
I've begun to re-evaluate every system I work on, reconsidering how interface choices impact overall efficiency
#SystemsProgramming
www.youtube.com/watch?v=yKgf...
I've begun to re-evaluate every system I work on, reconsidering how interface choices impact overall efficiency
#SystemsProgramming
www.youtube.com/watch?v=yKgf...
You should benchmark your algorithms. {thread}
While working on Zedis (check it out, please 🙏 github.com/barddoo/zedis), I was micro-optimizing it to achieve Redis performance, so I added a SIMD equality checker to make the most of the key-value hash table.
#Zig #Algorithms
While working on Zedis (check it out, please 🙏 github.com/barddoo/zedis), I was micro-optimizing it to achieve Redis performance, so I added a SIMD equality checker to make the most of the key-value hash table.
#Zig #Algorithms
October 15, 2025 at 8:41 PM
You should benchmark your algorithms. {thread}
While working on Zedis (check it out, please 🙏 github.com/barddoo/zedis), I was micro-optimizing it to achieve Redis performance, so I added a SIMD equality checker to make the most of the key-value hash table.
#Zig #Algorithms
While working on Zedis (check it out, please 🙏 github.com/barddoo/zedis), I was micro-optimizing it to achieve Redis performance, so I added a SIMD equality checker to make the most of the key-value hash table.
#Zig #Algorithms