Harness Engineering 10. From Documents to an Observable Harness
A practical roadmap for moving from document-centered operations to an observable harness.
Security, Rust, and AI Engineering Notes
This blog covers malware analysis, Rust, AI tooling, and harness engineering. Posts are organized in Korean and English around document malware research, Rust learning guides, and practical writing about AI system operations.
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Rust 11. File I/O and Command-Line Input
Rust guide to file and CLI input with std::fs::read_to_string, write, std::env::args, and Result.
Harness Engineering 09. Agent Systems Need Approval Boundaries and Guardrails
Explains why agent systems become unstable when approval boundaries and guardrails are missing.
Rust 10. Testing in Rust
Beginner-friendly Rust testing guide to cargo test, unit tests, integration tests, assert_eq!, and Result-based tests.
Harness Engineering 08. Results Alone Are Not Enough; You Need Trace
Explains why results alone are not enough and why trace matters for operations, debugging, and evaluation.
Rust 09. Crates, Packages, and Project Layout
Rust guide to crates, packages, main.rs, lib.rs, mod, use, and pub in a Cargo project.
Harness Engineering 07. Turning Principles into Enforceable Rules
Explains how to turn natural-language principles into concrete system rules and enforcement.
Rust 08. Vec, String, &str, and HashMap Basics
Beginner-friendly Rust guide to Vec, String, &str, and HashMap with examples and a word-frequency walkthrough.
Harness Engineering 06. Multi-Agent Is Not the Default
Explains why multi-agent setups are not the default answer and when a single agent is the better baseline.
Rust 07. Modules, Smart Pointers, Concurrency, and Async
Rust fundamentals guide to modules, smart pointers, concurrency, and async with examples.
Harness Engineering 05. Build and Test Are Not Enough to Validate an Agent
Explains why build and test alone are not enough to validate an agent and what extra checks are needed.
Rust 06. Generics, Error Handling, Closures, and Iterators
Rust fundamentals guide to generics, error handling, closures, and iterators with examples.
Harness Engineering 04. From Prose to Schema: Turning Handoff into a Contract
Explains why handoffs should move from free-form prose to schema-based contracts and how to design them.
Rust 05. Structs, Enums, Pattern Matching, and Traits
Rust fundamentals guide to structs, enums, pattern matching, and traits with examples.
Harness Engineering 03. How Far Should a Project Instruction File Go?
Explores what a project instruction file should own and where it should stop inside a larger harness.
Harness Engineering 02. What Is Harness Engineering?
Explains harness engineering as the design of the tools, permissions, and verification around AI.
Harness Engineering 01. Why Do Results Change When You Switch AI Coding Tools?
Explains why AI coding tools produce different results by looking beyond prompts to the execution environment.
Rust 04. Ownership, Borrowing, and Lifetimes
Rust fundamentals guide explaining ownership, borrowing, and lifetimes through examples.
Rust 03. Variables, Types, Control Flow, and Functions
Beginner guide to Rust variables, basic types, control flow, and functions with examples.
Rust 02. Debugging with rust-analyzer and CodeLLDB
Practical VS Code guide to debugging Rust projects with rust-analyzer and CodeLLDB.
Rust 01. Install Rust and Run Hello World
Beginner-friendly guide to installing Rust on Windows with VS Code and running Hello World.
[RTF] Analysis of a Document-Based Malware Sample
Analysis of an RTF-based malware sample, focusing on its exploit chain and execution flow.
[Macro] Analysis of a Document-Based Malware Sample
Analysis of a macro-based document malware sample, covering its execution flow and dropper behavior.