🍔🧠 How Amazon S3 Crushed The CAP Theorem (Deep Dive)

PLUS: GeoHashing Explained 🌍, AI Cookbook for Devs 📖 , AI Agents In Prod 🤖

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Happy Monday! ☀️

Welcome to the 461 new hungry minds who have joined us since last Monday!

If you aren’t subscribed yet, join smart, curious, and hungry folks by subscribing below.

📚 Software Engineering Articles

• Context engineering for AI code reviews

• Four promotions are all you need to reach Staff+ level

• Five impactful books that transformed a CTO's career

• Learn efficient geohashing for location-based data structures

• Vercel's revolutionary serverless servers change cloud computing

• Modern CSS capabilities might eliminate the need for SPAs

🗞️ Tech and AI Trends

• Neuralink joins research to develop bionic eye technology

• Revolutionary HIV prevention drug shows 100% effectiveness

• Humanoid robot becomes affordable at under $6,000

👨🏻‍💻 Coding Tip

• Use Rust's impl Trait for zero-cost abstractions in complex iterator chains

Time-to-digest: 5 minutes

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Context engineering for AI code reviews

CodeRabbit is an AI code reviewer with a multi-layered approach to context preparation that addresses code quality challenges for orgs and delivers consistently high-quality code reviews.

CodeRabbit doesn’t just point out issues; it delivers context-aware reviews on PRs, suggests 1-click fixes, and explains the reasoning behind the suggestions.

Learn more about context engineering for AI code reviews and how you can cut code review time in half with CodeRabbit.

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How Amazon S3 Achieves Strong Consistency at Scale 🫨

Amazon S3 powers countless applications by storing trillions of objects. While eventual consistency is simpler to implement in distributed systems, S3 managed to achieve strong consistency without sacrificing its legendary performance and availability.

The challenge: Building a strongly consistent object storage system that can handle 10M requests/second across 100T objects while maintaining sub-millisecond latency.

Implementation highlights:

1. Write-through caching: Updates cache first, then metadata store synchronously to prevent stale data

2. Witness service: Lightweight in-memory component that tracks latest versions and validates cache freshness

3. Transaction logging: Maintains operation order in metadata store to verify consistency

4. Smart read path: Queries cache first, validates with witness, falls back to metadata store if needed

5. Horizontal scaling: Distributes witness servers and handles failures through quick replacements and traffic redistribution

Results and learnings:

• Achieved strong read-after-write consistency without compromising performance

• Handles 10M requests/second across 100T objects

• Simplified application logic by handling consistency at the storage layer

S3's approach shows that with clever architecture choices, you can achieve both strong consistency and massive scale. It's proof that sometimes the best solutions come from combining simple ideas in smart ways.

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What is GeoHashing?

Written by

Ashish Pratap Singh

What is GeoHashing?

The art and science of context engineering

Context engineering is the difference between an AI code review tool that merely pattern-matches and one that deeply understands your specific codebase

Career Frameworks 🪜

Written by

Nicola Ballotta

and

Luca Rossi

Career Frameworks 🪜

5 books that changed my engineering career forever

Written by

Dr Milan Milanović

5 books that changed my engineering career forever

Companies Should Hire More Engineers in the Age of AI

Written by

Gregor Ojstersek

Companies Should Hire More Engineers in the Age of AI

🏆 You only need 4 promotions: The step-by-step guide from Junior to Staff+ engineer

Written by

Fran Soto

🏆You only need 4 promotions: The step-by-step guide from Junior to Staff+ engineer

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ESSENTIAL (lazy genius vibes)
The Case For Being Lazy

GITHUB REPO (code whisperer)
Qwen3-Coder is the code version of Qwen3

GITHUB REPO (chefGPT)
Examples and tutorials to help developers build AI systems

GITHUB REPO (sneaky telemetry)
Performance and Telemetry Analysis of Trae IDE

ARTICLE (SPA funeral)
It's time for modern CSS to kill the SPA

ARTICLE (date-night disaster)
Never write your own Date Parsing Library

ARTICLE (svg-party-tricks)
A Friendly Introduction to SVG

ARTICLE (robot overlords 101)
Six Principles for Production AI Agents

ARTICLE (focus-fail)
When Software Engineers Think They Need More Focus Time

ARTICLE (serverless sorcery)
Fluid compute: How we built serverless servers

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Want to reach 190,000+ engineers?

Let’s work together! Whether it’s your product, service, or event, we’d love to help you connect with this awesome community.

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👁️ Elon Musk’s Neuralink Joins Study Working Toward a Bionic Eye (2 min)

Brief: Elon Musk’s Neuralink partners with researchers to develop a bionic eye, aiming to restore or enhance vision using brain-computer interface technology.

💉 FDA Approves First 100% Effective HIV Prevention Drug (3 min)

Brief: The FDA has approved lenacapavir (Yeztugo), the first twice-yearly injectable HIV prevention drug with 100% efficacy, while Gilead waives royalties to expand global access in high-risk regions.

🤖 China’s Unitree R1 Humanoid Robot Priced Under $6,000 (2 min)

Brief: Chinese robotics firm Unitree unveils R1, a humanoid robot priced below $6,000, aiming to accelerate affordable automation in industries and homes.

🚀 Figma Shares Soar 250% in NYSE Debut After $33 IPO (3 min)

Brief: Design software giant Figma surges to a $68B market cap in its NYSE debut, defying expectations after its $20B Adobe deal collapsed in 2023 due to antitrust concerns.

🚀 Coinbase Expands Into Tokenized Stocks and Prediction Markets for US Users (3 min)

Brief: Coinbase plans to launch tokenized stocks, derivatives, and prediction markets in the US within months, aiming to become a one-stop on-chain trading platform amid regulatory shifts.

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This week’s coding challenge:

Build Your Own Redis

This week’s tip:

Use Rust's zero-cost abstractions with `impl Trait` to maintain performance while hiding complex types. This pattern allows you to return complex iterator chains or closures without explicitly typing them, while still generating optimal code at compile time.

Wen?

• Complex iterator chains: Hide multi-step transformations behind a clean interface while maintaining zero-cost abstraction.

• Return type flexibility: Allow internal implementation changes without affecting public API signatures.

• Generic code optimization: Enable the compiler to monomorphize and inline code across abstraction boundaries for maximum performance.

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“There is an essence of when you are fearless, you become more creative.”
Gurbaksh Chahal

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That’s it for today! ☀️

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See you in a week — Alex.

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