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Built a Markdown editor using Rust + egui. v0.2.1 just dropped with major Mermaid improvements:

→ Native Mermaid diagrams - Flowcharts, sequence, state, ER, git graphs - pure Rust, no JS

→ Split view - Raw + rendered side-by-side with sync scrolling

→ Syntax highlighting - 40+ languages with large file optimization

→ JSON/YAML/TOML tree viewer - Structured editing with expand/collapse

→ Git integration - File tree shows modified/staged/untracked status

Also: minimap, zen mode, auto-save, session restore, code folding indicators.

~15MB binary, instant startup. Windows/Linux/macOS.

GitHub: https://github.com/OlaProeis/Ferrite

v0.2.2 coming soon with performance improvements for large files. Looking for feedback!

I built a system for Claude Code to browse 100 non-fiction books and find interesting connections between them.

I started out with a pipeline in stages, chaining together LLM calls to build up a context of the library. I was mainly getting back the insight that I was baking into the prompts, and the results weren't particularly surprising.

On a whim, I gave CC access to my debug CLI tools and found that it wiped the floor with that approach. It gave actually interesting results and required very little orchestration in comparison.

One of my favourite trail of excerpts goes from Jobs’ reality distortion field to Theranos’ fake demos, to Thiel on startup cults, to Hoffer on mass movement charlatans (https://trails.pieterma.es/trail/useful-lies/). A fun tendency is that Claude kept getting distracted by topics of secrecy, conspiracy, and hidden systems - as if the task itself summoned a Foucault’s Pendulum mindset.

Details:

* The books are picked from HN’s favourites (which I collected before: https://hnbooks.pieterma.es/).

* Chunks are indexed by topic using Gemini Flash Lite. The whole library cost about £10.

* Topics are organised into a tree structure using recursive Leiden partitioning and LLM labels. This gives a high-level sense of the themes.

* There are several ways to browse. The most useful are embedding similarity, topic tree siblings, and topics cooccurring within a chunk window.

* Everything is stored in SQLite and manipulated using a set of CLI tools.

I wrote more about the process here: https://pieterma.es/syntopic-reading-claude/

I’m curious if this way of reading resonates for anyone else - LLM-mediated or not.

I ported the teaching OS xv6-riscv to HiFive Unmatched and got it running on real hardware, including passing usertests.

I've been self-studying OS internals using the MIT 6.1810 materials. After finishing most of the labs, I was eager to see what it's like to run the OS on bare metal, rather than QEMU.

The Unmatched may not have the latest RISC-V features, but it's well-documented, and the Rev B release has made it more affordable, which makes it a good learning platform.

The porting process involved several interesting challenges:

- Hardware Quirks: Handling things like enabling A/D bits in PTEs (the hardware doesn't set them automatically, causing page faults), proper handling of interrupts, and instruction cache synchronization.

- Boot Flow: xv6 expects M-mode on startup, but standard RISC-V boot flows (typically via OpenSBI) jump to S-mode. To bridge this gap, I created a minimal U-Boot FIT image that contains only the xv6 kernel. This way, U-Boot SPL handles the complex CPU/DDR initialization, then hands control to xv6 in M-mode (skipping OpenSBI).

- Drivers: Ported an SPI SD card driver, replacing the virtio disk driver.

I wrote up implementation notes here: https://github.com/eyengin/xv6-riscv-unmatched/blob/unmatche...

Hopefully, this is useful for others who are learning OS internals and want to try running their code on real RISC-V hardware.

https://sprites.dev/