
SystemDecoder
Build. Simulate. Learn.
What it does
Learn system design by simulating real-world behavior. Visualize latency, load, failures, and system flow interactively.
Does the same job
all alternatives →
- VFVisualizer for High Level System Design2021 · honzaap.github.io · ▲167

- DTDebugger that generates video visualizations for algorithm learning2020 · github.com · ▲102

PRISM — Learn System DesignJun 2026 · prismhld.com · ▲3Learn System Design by Building Real Architectures
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The first open-source price index for GPU compute
Dev tools · 10d ago · getcomputable.com

OpenTrailPaper is open-source bike computer firmware for the LilyGO T5S3 4.7" E-Paper PRO. It supports offline maps, GPX routes, FIT recording and Bluetooth sensors.
Dev tools · 2d ago · opentrailpaper.com

Open-source GTM skills for technical founders
Dev tools · 29d ago · gtmcofounder.com
Launched alongside, May 2026
the whole month →

Parallel agents, diff reviewer, and multi-model comparisons
Dev tools · May 2026 · kilo.ai


- NW
Hey HN, Henry here from Cactus. We open-sourced Needle, a 26M parameter function-calling (tool use) model. It runs at 6000 tok/s prefill and 1200 tok/s decode on consumer devices. We were always frustrated by the little effort made towards building agentic models that run on budget phones, so we conducted investigations that led to an observation: agentic experiences are built upon tool calling, and massive models are overkill for it. Tool calling is fundamentally retrieval-and-assembly (match query to tool name, extract argument values, emit JSON), not reasoning. Cross-attention…
Life & fun · May 2026 · github.com
- FM
Dev tools · May 2026 · github.com