SamueL⚡

||Focus on the focus||@fcbarcelona

[Kafui Dey @KafuiDey]

East Legon Roasted Plantain Vendors & The Baking Break Phenomena

Prof. Nii Narku Quaynor raises concerns about how quickly people imitate a new business idea when they see someone succeed with it.

Prof. argues that it is better to support the original ideas to succeed and become bigger.

Watch full interview here https://t.co/n7W9MXzTta

#KafuiDeyInterviews

[Reshad Rahman @ReshadRahman]

⚡️ Lamine Yamal: “At PSG, everyone presses, and here at Barcelona, we're also trying to have everyone press. I might lose focus sometimes, but I quickly get back to pressing” 🔵🔴

“In modern football, if you don't run, any team will outpace you, no matter who you are or what your name is” 💨

“If we don't run tomorrow, they'll beat us. In the end, it's about the team's best interest; if we want to win, we have to run, and if we don't, we'll lose, it's that simple” #FCB 👀🏃‍♂��

[Puneet Patwari @system_monarch]

I've been a backend Engineer for 12+ years. Today, I'm a Principal Engineer at Atlassian.

I've designed systems that handle millions of requests. Sat on both sides of system design interviews.

Reviewed more architecture docs than I can count.

Starting today, I'm breaking down the fundamentals of scaling for the next 25 days.

If you're learning system design bookmark this thread, you're going to get a lot of learning from this.

[Sarkodie @sarkodie]

The O2 London 6th of march 2027 #Rapperholic27UK #TheO2London

[Reads with Ravi @readswithravi]

“You escape competition through authenticity.”

— Naval Ravikant

[QuickSedis 🟢 @QuickSedis]

Trade Crypto with QuickSedis

Convert crypto to Cash in minutes. No complex wallets, no confusing interfaces. Just simple, fast transactions.

👉🏽 https://t.co/X4AhVAIzeG

[Vivo @vivoplt]

Don’t overcomplicate it.

• Build a Password Manager to learn file handling, hashing (not full crypto)
• Build a URL Shortener to understand routing, IDs, and persistence
• Build a Todo App with deadlines to practice CRUD and basic state
• Build a Web Scraper to learn requests, parsing, and rate limits
• Build a CLI Expense Tracker to master logic, files, and edge cases
• Build a Log Analyzer to work with files, timestamps, and patterns
• Build a Simple Recommender using similarity rules (not ML magic)
• Build an Email Automation Script using SMTP and scheduling

Projects. Not tutorials.

[SumitM @SumitM_X]

Few ppl asked me - How long did it take to prepare the Java interview ebook , one month?

Well, It’s the culmination of years—yes 14 years—of reading these books

14 years in this field and Thousands of interviews !

[Kyros @IamKyros69]

Elon Musk on how to actually start a company

[Startup Archive @StartupArchive_]

Elon Musk explains how to get startup ideas

When asked how he comes up with startup ideas, Elon responds:

“I tend to think of things from a sort of physics standpoint… what’s the best way to accomplish something? And then pursue that. That’s also a good way to determine if something’s far from its optimum.”

He gives rockets as an example:

“You could reason by analogy and say the rocket is going to cost a certain amount because that’s what prior rockets have cost. Or you can say, well, what is a rocket made of? What are the material constituents? What do they weigh? What’s the cost per unit mass? And that sets the limit asymptotically for what a rocket can be. So if you can figure out some creative way to rearrange those elements into a rocket shape, then you can achieve a much better outcome.”

He also thinks combining ideas from different industries is really helpful for innovation:

“What have people discovered in one industry and can that be applied to other industries? That’s I think also a great source of ideas. But usually you just struggle on a solution and try a bunch of things. Most of them don’t work and occasionally one does.”

Video source: @VanityFair (2014)

[Rohan Paul @rohanpaul_ai]

Fei-Fei Li says language models are extremely limited.

This @GoogleDeepMind paper makes almost the same point, just in the world of video.

The models are just very advanced pattern matchers. They can recreate what looks like reality because they’ve seen so much data, but they don’t know why the world works the way it does.

The models can generate clips that look stunningly real, but when you test whether they actually follow basic physics, they fall apart.

The Physics-IQ benchmark shows that visual polish and true understanding are two completely different things.

Here, the authors build Physics-IQ, a real-video benchmark spanning solid mechanics, fluids, optics, thermodynamics, and magnetism

Each test shows the start of an event, then asks a model to continue the next seconds.

They compare the prediction to the real future using motion checks for where, when, and how much things move.

Scores then roll into a single Physics-IQ number that caps at what 2 real takes agree on.

Across popular models, even the strongest sits far below that cap, while multiframe versions usually beat image-to-video versions.

Sora is hardest to tell apart from real videos, yet its physics score stays low, showing realism and physics are uncorrelated.

Some cases work, like paint smearing or pouring liquid, but contact and cutting often fail.

arxiv. org/abs/2501.09038

[SamueL⚡ @SamueL___Y]

@bRutTe_forc3 CP

[ₕₐₘₚₜₒₙ @hamptonism]

The Secret World of Central Bankers:

[Mustafa. @oprydai]

study graph theory

the entire universe runs on connections.
neurons, roads, networks, friendships, computers, logistics, even ideas; all are graphs.

graph theory is the math of relationships. it teaches you how things interact, not just what they are.
you’ll start seeing everything as nodes and edges; and suddenly, complexity starts making sense.

internet routing? graphs.
social networks? graphs.
neural networks? graphs.
supply chains, power grids, ecosystems? all graphs.

if you study graph theory deeply, you won’t just understand systems; you’ll see through them.

[Naval @naval]

Good Products Are Hard to Vary.

[Nesta’🫱🏽‍🫲🏾🇬🇭 @eddie_nesta_o]

Open for internship/ Graduate trainee positions🙏🏾

[Fernando @Franc0Fernand0]

11. Bit Manipulation

⬩Basic Bit Operations: AND, OR, XOR, NOT, left shift, and right shift
⬩Common Bit Tricks: Checking if a number is even/odd, counting set bits, finding unique numbers
⬩Power of Two: Checking if a number is a power of two
⬩Swapping Numbers: Using XOR for in-place swapping
⬩Masking and Bit Counting: Using masks for problems like subsets and permutations

[Makakmayum @makakmayum_sid]

For experienced Java engineers/developers, one is tested under pressure to check their knowledge related to memory and latency. Here are a few scenarios and what I would do to debug in those scenarios:

1. High Garbage Collection & Latency
Question: You get an alert that a critical service has high CPU usage and is experiencing severe latency spikes. It hasn't crashed, but it's barely usable. What's your immediate plan?
Answer→ First, I'd check the GC logs and application metrics to confirm frequent Full GCs. Then, I'd use a profiler or take a heap dump to find which objects are consuming the most memory. The fix is usually to optimize memory-heavy code, tune JVM heap/GC parameters, and validate the changes with a load test.

2. The Mysterious Memory Leak
Question: A service runs perfectly after a restart but crashes with an OutOfMemoryError after about 10-12 hours. What's your strategy to find and fix the root cause?
Answer: This strongly suggests a memory leak. I'd configure the JVM to capture a heap dump on OutOfMemoryError. Then, I'll use an analyzer like Eclipse MAT to identify objects that are growing in number but should have been garbage collected. Common culprits are unclosed resources, static collections, or improper session handling.

3. The Slow Database Connection
Question: Users are reporting that the application is frequently timing out. Your dashboard shows that most of your service's threads are stuck waiting for a database connection. How do you solve this?
Answer: Threads waiting for connections means the database is the bottleneck. My first step is to enable slow query logging to find the exact SQL statements that are taking too long. The solution is a mix of optimizing the queries, adding necessary database indexes, and tuning the connection pool settings. Adding a caching layer for frequently accessed data is also a great long-term fix.

4. The Application Deadlock
Question: Your application suddenly becomes completely unresponsive under load, but the CPU isn't maxed out. What do you suspect is happening, and how do you prove it?
Answer: This is a classic sign of a thread deadlock. My immediate action would be to take a thread dump using jstack. I'd then analyze the dump to find threads in the BLOCKED state and identify the circular dependency where Thread A is waiting for a lock held by Thread B, and Thread B is waiting for a lock held by Thread A.

[Shraddha Bharuka @BharukaShraddha]

🚀 𝗦𝘆𝘀𝘁𝗲𝗺 𝗗𝗲𝘀𝗶𝗴𝗻 is one of the toughest parts of interviews for SDE roles.

To help you, I have compiled multiple System Design Notes📘 that will make your prep easier.

✅ Covers important concepts
✅ Easy to understand
✅ Interview-focused

Just:

1. Repost, Follow and Like
2. Comment [FREE]

And I will DM you

Save this post for later & start your preparation today!

#systemdesign #interviewprep #softwareengineering #sde