Good To Know

Linux kernel mechanisms that determine how backend and trading systems use memory, CPU, I/O, and isolation in production.

next: Virtual Memory & Paging Page Cache & Writeback CPU Scheduling (CFS & EEVDF) Syscalls, vDSO & Context-Switch Cost epoll & Readiness-Based I/O

Protocols, kernel networking, and infrastructure that govern connectivity, throughput, and latency between production services.

next: IP Addressing, Forwarding & Route Selection BGP, Interdomain Routing & Policy TCP Handshake & State Machine TCP Congestion Control Sockets API & Socket Options

Concurrent execution models, synchronization primitives, and coordination patterns for building correct and fast multithreaded and async systems.

next: Memory Models & Ordering Atomics & Compare-and-Swap Locks, Mutexes & Condition Variables Async I/O & Event Loops Threads vs Processes

How independent machines coordinate over unreliable networks — time, consensus, replication, consistency models, and the failure modes that break production systems.

next: Linearizability Leases, Fencing Tokens & Distributed Locks Idempotency & Exactly-Once Semantics Partitioning & Consistent Hashing Physical Clocks, NTP & Clock Skew

How relational and specialized data stores work under the hood — storage engines, transactions, query execution, replication, and operating Postgres and Redis at scale.

next: B-Tree vs LSM Storage Engines WAL & Crash Recovery Indexing Strategies Query Planning & EXPLAIN Connection Pooling

Designing systems that survive real traffic — capacity math, caching, streaming, flow control, and the scaling patterns that keep latency flat as load grows.

next: Backpressure & Load Shedding Rate Limiting Hot Keys & Hot Partitions WebSockets & SSE at Scale Sharding & Request Routing

Measuring, modeling, and optimizing the latency and throughput of production systems from CPU microarchitecture up to capacity planning.

next: Performance Methodology: USE & RED Profiling with perf & Flamegraphs Latency Percentiles & Coordinated Omission CPU Caches & the Memory Hierarchy Benchmarking Pitfalls & Statistics

Instrumenting, measuring, and debugging production systems — metrics, logs, traces, SLOs, alerting, and the operational practice built on top of them.

next: Metric Types & Instrumentation Histograms, Percentiles & Latency Analysis Alerting Design Cardinality Management Structured Logging

How instruction-set contracts become processor, memory, bus, machine-code, boot, and protection behavior — from the compact 8086 model through modern x86-64 kernel entry.

next: Microprocessor Systems: CPU, Memory, Buses & I/O Microcontroller Architecture & Peripheral Contracts Microcontroller Clock, Reset, Power & Watchdog Microcontroller GPIO & Pin Multiplexing Microcontroller Interrupts & Event Handling

The working mathematics behind engineering — linear algebra, calculus, numerical computing, signals & transforms, probability & statistics, optimization, and information theory, at the depth a software engineer actually uses.

next: Rounding Error & Catastrophic Cancellation Decimal, Fixed-Point & Integer Money Arithmetic Eigenvalues & Eigenvectors Matrix Decompositions (LU, QR, SVD) Affine & Projective Transforms (Homogeneous Coordinates)

The discrete structures under computer science — logic and proofs, sets and relations, combinatorics, graph theory, number theory, and automata — and where each shows up in everyday engineering.

next: Divisibility, GCD & Modular Arithmetic Complexity Classes: P & NP Proof Techniques & Induction Recurrences & Generating Functions Minimum Spanning Trees

How modern cryptography actually works and how it is deployed — primitives, protocols, PKI, and the ways real systems get it wrong.

next: Modes of Operation & AEAD (GCM) TLS 1.3 Handshake JWT & Token Security Pitfalls Password Storage (bcrypt & Argon2) Common Implementation Failures

Replicated ledgers whose ordering and validity are secured by consensus, cryptography, peer-to-peer networking, and explicit economic or membership assumptions.

next: Ledgers, Transactions & State Transitions Nakamoto Consensus & Probabilistic Finality Ethereum Execution, Consensus & Networking Bitcoin Transactions, Script & Signatures Bitcoin Peer-to-Peer Protocol

How financial markets turn heterogeneous information and risk-bearing capacity into prices, liquidity, execution, and inventory exposure.

next: Probability & Uncertainty in Trading Binary YES/NO Contracts Price as Implied Probability Realized PnL of a Binary Contract Expected Value of Binary Contracts

Lumped electrical networks from variables and conservation laws through DC and sinusoidal steady-state analysis, network theorems, coupled coils, two-port models, and parameter identification from measured waveforms.

next: Lumped-Circuit Variables, Reference Directions & Sign Conventions Ideal Sources, Resistors, Capacitors & Inductors Circuit Topology, KCL & KVL Nodal-Voltage Analysis & Supernodes Mesh-Current Analysis & Supermeshes

Semiconductor devices and the circuits built from them — analog amplification, feedback, waveform shaping, mixed-signal conversion, and digital logic from gates through state machines.

next: Semiconductor Physics & p-n Junctions Diodes, Rectifiers, Clampers & Voltage References Bipolar Junction Transistors Field-Effect Transistors Transistor Amplifiers, Biasing & Small-Signal Models

Turning an electronic circuit into controlled, manufacturable hardware — requirements, parts, PCB construction and layout, assembly, production data, verification, and reliability.

next: Component Selection, Derating, Lifecycle & BOM Control PCB Types, Stackups, Materials & Fabrication PCB Routing, Return Paths & Power Distribution Signal Integrity, Power Integrity & EMC at Board Level Electrical Safety, Current Capacity & Thermal Design

Turning continuous phenomena into sampled numbers and back — sampling and quantization, the z-transform, filter design and stability, spectral analysis, perceptual compression, and the hardware built to run it.

next: The Z-Transform & Region of Convergence Convolution & Correlation Filter Stability & the Unit Circle Audio Compression & Psychoacoustic Models DSP Processors: MAC, Harvard Memory & Circular Addressing

The structures that hold data and the strategies that search it — complexity analysis, the core container types and what they cost, algorithm design patterns, sorting, and string matching.

next: Dynamic Programming & Memoization Probabilistic Structures: Bloom Filters & Sketches Divide & Conquer Amortized Analysis Greedy Algorithms & Exchange Arguments

How geometry becomes pixels — raster fundamentals and color, the transform and camera pipeline, real-time rendering and shading, and the curves and procedural methods used to describe shape.

next: Raster Images, Pixel Formats & Color Spaces 2D Transform Pipeline & Coordinate Systems 3D Projection & Camera Models The Real-Time Rendering Pipeline Line & Polygon Rasterization

Understanding wholes without losing the parts — boundaries and context, structure and emergence, state and adaptation, disciplined problem framing, model views, and decision models across a system life cycle.

next: System Boundaries, Context & Purpose Systems Analysis & Problem Framing Structure, Interactions & Emergent Behavior State, Behavior, Feedback & Adaptation Decomposition, Aggregation & Model Views

Building models of real systems and steering them — dynamic representations, identification from data, simulation, feedback, sampled and switching control, tracking, and robustness under uncertainty.

next: Model Adequacy, Validation & Overfitting Pseudorandom Generators for Simulation Simulating Dynamics: Step Size, Drift & Solver Choice Model Classes & When Each Is Appropriate Analytical, Empirical & Simulation Models

Control systems that combine feedback with structured knowledge, approximate reasoning, online adaptation, or learned models — while keeping authority, timing, stability evidence, and safety constraints explicit.

next: Intelligent-Control Architectures & Timescale Hierarchies Fuzzy Sets, Linguistic Variables & Approximate Reasoning Fuzzy Modeling, Identification & Control Adaptive Control, Self-Tuning & Gain Scheduling Neural System Identification & Learning-Enabled Control

Getting information across a physical channel — propagation and link budgets, modulation and detection, distortion and fading, the coding that survives a noisy channel, and the radio systems built on top.

next: Digital Modulation: ASK, FSK, PSK & QAM Channel Coding: Hamming Distance, Code Rate, ARQ vs FEC The Transmission Chain, Source to Sink Radio Propagation & Free-Space Attenuation Noise Sources: Thermal, Atmospheric & Man-Made

How code is shaped rather than what it computes — type systems and object semantics, the modelling decisions that decide what a change costs later, error and lifetime contracts, serialization boundaries, and the pattern vocabulary teams argue in.

next: Type Systems: Static, Dynamic, Strong & Weak Value vs Reference Semantics, Copying & Aliasing Encapsulation as Invariant Protection Inheritance vs Composition Polymorphism & Dispatch: vtables, Interfaces and Their Cost

How software tests produce trustworthy change evidence — from fast behavioral checks and controlled dependencies to real integrations, concurrent execution, browser journeys, executable acceptance examples, and safe work in legacy code.

next: Testing Strategy: Scope, Cost & Evidence Unit Testing: Deterministic Fixtures, Actions & Oracles Integration Testing with Real Dependencies Test-Driven Development: Red, Green & Refactor Test Doubles: Dummies, Stubs, Spies, Fakes & Mocks

Learning a decision rule from data instead of writing it — how a problem is framed and split, the supervised and unsupervised model families and what each is actually good at, neural networks from the perceptron up, and the evaluation and monitoring without which a model's reported accuracy means nothing.

next: Semi-Supervised & Active Learning Recommender Systems & Preference Learning Multi-Label Learning & Missing Labels Differentiable Memory & Neural Computers Neural Audio Generation

The control-system software and operations layer — controller execution, PLC programming models, supervisory architectures, operator interfaces, alarms, industrial protocols, historians, and engineering documentation.

next: Industrial Control-System Architecture: PLC, DCS, SCADA & HMI PLC Execution: Tasks, Scan Cycles, I/O Images & Remote I/O IEC 61131-3 Programming Model: POUs, Tasks, ST, LD, FBD & SFC Sequential Control, Interlocks & Permissives Process Alarm Management

The physical layer of automated systems — measurement transducers, electromagnetic devices, electric machines and drives, and the power electronics that connect them to control loops.

next: Measurement Transducers: Static & Dynamic Characteristics Pressure Measurement, References & Transmitters Flow-Measurement Technologies & Installation Effects Level-Measurement Technologies & Applications Control Valves & Final Control Elements