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RAG Clearly Explained
The mental model every engineer should have.
10 hrs ago
•
Nikki Siapno
24
5
How Discord Fans Out One Message to a Million Users
A case study in fanout, bottlenecks, and the engineering decisions behind Discord's scale.
Jul 7
•
Nikki Siapno
19
1
2
June 2026
LLMs: The Essential Guide
Most engineers only see the API layer. Here's what's happening underneath.
Jun 26
•
Nikki Siapno
36
4
MCP Clearly Explained
Plus: Big upgrades are coming to LUC. Vote on what you'd like to see first.
Jun 15
•
Nikki Siapno
46
3
5
May 2026
REST vs GraphQL vs gRPC
The tradeoffs behind resource-driven, query-driven, and method-driven APIs.
May 28
•
Nikki Siapno
36
7
Service Discovery in Distributed Systems Clearly Explained
How modern systems dynamically locate healthy services as infrastructure constantly changes.
May 13
•
Nikki Siapno
17
2
Docker vs Kubernetes
(4 min read) | The real difference that actually matters, how to decide, where teams go wrong, and more...
May 11
•
Nikki Siapno
35
2
2
OAuth Clearly Explained
(4 min read) | OAuth flow, three different tokens, three different jobs, what OAuth actually solves, where OAuth systems usually break, and more
May 1
•
Nikki Siapno
105
1
14
April 2026
Infrastructure as Code Clearly Explained
The IaC workflow that actually works, why it matters in practice, security risks you can't ignore, and more...
Apr 27
•
Nikki Siapno
18
3
Redis Clearly Explained
How Redis works under the hood, where it fits in the stack, where it shines, and when NOT to use it.
Apr 21
•
Nikki Siapno
88
3
10
Database Indexing Clearly Explained
(4 minutes) | What indexes really do, index types, how the optimizer decides, when they help (and when they hurt), and the right mental model
Apr 13
•
Nikki Siapno
47
2
7
Circuit Breakers: How to Stop Small Failures from Spreading
(4 Minutes) | What they are, what triggers a trip, why they help so much, observability, and when to use them (and when not to)
Apr 9
•
Nikki Siapno
20
3
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