Aneesh Kulkarni

Talks about tech, cricket and much more!!

[Aneesh Kulkarni @Anee_Kulkarni12]

I built a sharded, durable key-value store from scratch in Go.

No tutorials. No frameworks. Just the primitives that real
databases are made of.

Here's what I learned across 6 stages 🧵

[Aneesh Kulkarni @Anee_Kulkarni12]

@solyatic Heyy, happy to connect !

[Aneesh Kulkarni @Anee_Kulkarni12]

Every optimization should come with an ablation. Otherwise you're
guessing.

[Aneesh Kulkarni @Anee_Kulkarni12]

A benchmark taught me more about distributed systems than any
tutorial:
Unsharded, 4 cores: 152 ns/op
Sharded, 4 cores: 65 ns/op
But the real lesson was when I broke it on purpose (all keys → 1 shard):
458 ns/op. Worse than unsharded.

[Aneesh Kulkarni @Anee_Kulkarni12]

@Ali_Homsi @X yupp kinda

[Aneesh Kulkarni @Anee_Kulkarni12]

@RoryStandley heyy, happy to connect !

[Aneesh Kulkarni @Anee_Kulkarni12]

@Ali_Homsi @X building a one right now !, will be using for couple of those once done ;)

[Aneesh Kulkarni @Anee_Kulkarni12]

@mukparekh Heyy !!

[Aneesh Kulkarni @Anee_Kulkarni12]

@NbSoloman @X Heyy

[Aneesh Kulkarni @Anee_Kulkarni12]

@Ali_Homsi @X kinda into distributed kv-store right now ;)

[Aneesh Kulkarni @Anee_Kulkarni12]

People ask how I learn this stuff.

The honest answer: I don't read more. I build smaller.

One stage at a time. One problem at a time. One bug at a time.

Depth compounds. Breadth doesn't.

[Aneesh Kulkarni @Anee_Kulkarni12]

@SiftByte @X Heyy

[Aneesh Kulkarni @Anee_Kulkarni12]

@_RoadTo10M Heyy, happy to connect !

[Aneesh Kulkarni @Anee_Kulkarni12]

The hardest part of building a database isn't the code.

It's the ordering constraints.

Snapshot before truncate.
Log before memory.
Rename before truncate directory.

Every one of them exists because someone, somewhere, lost data
by getting the order wrong.

[Aneesh Kulkarni @Anee_Kulkarni12]

Write-ahead log in one sentence:

Every write goes to disk BEFORE it goes to memory.

If you crash between the two, the log has it. If you crash the other
way, you lose it silently.

Order is not a suggestion. It's the whole thing.

[Aneesh Kulkarni @Anee_Kulkarni12]

@Ali_Homsi @X just roaming around high throughput systems, what's you are on ?

[Aneesh Kulkarni @Anee_Kulkarni12]

@byte_operator Heyy

[Aneesh Kulkarni @Anee_Kulkarni12]

@buildwithdk Heyy!

[Aneesh Kulkarni @Anee_Kulkarni12]

@KhalilNoaman Hey !

[Aneesh Kulkarni @Anee_Kulkarni12]

@hugo_deltour heyy