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The Speed Engineer

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The Speed Engineer

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Dec 3, 2025

What Actually Happened When We Turned On HTTP/3

We dropped mobile p99 latency by 40%. Then our CDN stopped talking to half our users.

What Actually Happened When We Turned On HTTP/3

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Beyond Localhost

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The Speed Engineer

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Nov 27, 2025

How We Handle 10M WebSocket Connections on a Single Server

We threw out the thread-per-connection model, pinned cores to NUMA nodes, and bypassed the kernel network stack. Here’s why your intuition…

How We Handle 10M WebSocket Connections on a Single Server

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The Speed Engineer

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Feb 9

We Finally Hit 50 Million Concurrent Users. 72 Hours Later, We Were Dead.

A $4.7 million AWS invoice. Twelve days of runway. One weekend to save the company or shut it down forever.

We Finally Hit 50 Million Concurrent Users. 72 Hours Later, We Were Dead.

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The Speed Engineer

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Jan 10

2026 Will Be Brutal for the Average Developer: Here’s How to Survive

The gold rush is over. If you’re still writing code like it’s the Zero Interest Rate Policy (ZIRP) era of 2021 — relying on abstractions…

2026 Will Be Brutal for the Average Developer: Here’s How to Survive

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Beyond Localhost

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The Speed Engineer

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Dec 26, 2025

Zero Trust Networking: Replacing API Keys with Mutual TLS (mTLS)

How a security incident forced us to replace 284 shared secrets with cryptographic identities — without breaking production.

Zero Trust Networking: Replacing API Keys with Mutual TLS (mTLS)

The Speed Engineer

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10h ago

You Shipped the Most Code. The Engineer Who Deleted It Got Promoted.

How to get credit for the risk you remove

You Shipped the Most Code. The Engineer Who Deleted It Got Promoted.

The Speed Engineer

·

2d ago

Can a Bigger Database Pool Make Your API Slower?

Past a point it does. The maths to find that point for your own service

Can a Bigger Database Pool Make Your API Slower?

The Speed Engineer

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4d ago

Can You Answer ‘Why Not Just Use a Database?’

The follow-up that separates a memorised design from one the candidate reasoned through

Can You Answer ‘Why Not Just Use a Database?’

The Speed Engineer

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Nov 5

How Google’s Region Went Dark

Google’s europe-west2-b went dark for six hours, and the healthy zones ran out of room catching it

How Google’s Region Went Dark

The Speed Engineer

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Nov 2

I’d Start Stateful Flink Jobs at Netflix’s 0.45 Utilisation, Not the 0.7 Default

By my maths it’s about 1.5 times the capacity. I’d pay it to restart less, since on defaults each restart blinds the scaler for 20 minutes.

I’d Start Stateful Flink Jobs at Netflix’s 0.45 Utilisation, Not the 0.7 Default

The Speed Engineer

The Speed Engineershe

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I break things in production for a living. Sometimes on purpose. I write about what the incident reports leave out.

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