🛠️ All DevTools

[Other] Show HN: Seapie – a Python debugger where breakpoints drop into a REPL

[Other] Show HN: Tylax – A bidirectional LaTeX to Typst converter in Rust Hi HN, author here.<p>I built Tylax because I wanted to migrate my old LaTeX papers to Typst but found existing regex-based scripts too fragile for nested environments.<p>Tylax parses LaTeX into an AST (using mitex-parser) and converts it to Typst code. It supports: - Full document structure (not just math snippets) - Complex math (matrices, integrals) - Experimental TikZ -&gt; CeTZ graphics conversion - Runs in browser via WASM<p>Repo: <a href="https:&#x2F;&#x2F;github.com&#x2F;scipenai&#x2F;tylax" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;scipenai&#x2F;tylax</a> Web Demo: <a href="https:&#x2F;&#x2F;convert.silkyai.cn&#x2F;" rel="nofollow">https:&#x2F;&#x2F;convert.silkyai.cn&#x2F;</a><p>Happy to answer any questions!

[Other] Show HN: 30k IKEA items in flat text OP here.<p>I took the unofficial IKEA US dataset (originally scraped by jeffreyszhou) and converted all 30,511 products into a flat, markdown-like protocol called CommerceTXT.<p>The goal: See if a flatter structure is more efficient for LLM context windows.<p>The results: - Size: 30k products across 632 categories. - Efficiency: The text version uses ~24% fewer tokens (3.6M saved total) compared to the equivalent minified JSON. - Structure: Files are organized in folders (e.g. &#x2F;products&#x2F;category&#x2F;), which helps with testing hierarchical retrieval routers.<p>The link goes to the dataset on Hugging Face which has the full benchmarks.<p>Parser code is here: <a href="https:&#x2F;&#x2F;github.com&#x2F;commercetxt&#x2F;commercetxt" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;commercetxt&#x2F;commercetxt</a><p>Happy to answer questions about the conversion logic!

[IDE/Editor] Show HN: KeelTest – AI-driven VS Code unit test generator with bug discovery I built this because Cursor, Claude Code and other agentic AI tools kept giving me tests that looked fine but failed when I ran them. Or worse - I&#x27;d ask the agent to run them and it would start looping: fix tests, those fail, then it starts &quot;fixing&quot; my code so tests pass, or just deletes assertions so they &quot;pass&quot;.<p>Out of that frustration I built KeelTest - a VS Code extension that generates pytest tests and executes them, got hooked and decided to push this project forward... When tests fail, it tries to figure out why:<p>- Generation error: Attemps to fix it automatically, then tries again<p>- Bug in your source code: flags it and explains what&#x27;s wrong<p>How it works:<p>- Static analysis to map dependencies, patterns, services to mock.<p>- Generate a plan for each function and what edge cases to cover<p>- Generate those tests<p>- Execute in &quot;sandbox&quot;<p>- Self-heal failures or flag source bugs<p>Python + pytest only for now. Alpha stage - not all codebases work reliably. But testing on personal projects and a few production apps at work, it&#x27;s been consistently decent. Works best on simpler applications, sometimes glitches on monorepos setups. Supports Poetry&#x2F;UV&#x2F;plain pip setups.<p>Install from VS Code marketplace: <a href="https:&#x2F;&#x2F;marketplace.visualstudio.com&#x2F;items?itemName=KeelCode.keeltest" rel="nofollow">https:&#x2F;&#x2F;marketplace.visualstudio.com&#x2F;items?itemName=KeelCode...</a><p>More detailed writeup how it works: <a href="https:&#x2F;&#x2F;keelcode.dev&#x2F;blog&#x2F;introducing-keeltest" rel="nofollow">https:&#x2F;&#x2F;keelcode.dev&#x2F;blog&#x2F;introducing-keeltest</a><p>Free tier is 7 tests files&#x2F;month (current limit is &lt;=300 source LOC). To make it easier to try without signing up, giving away a few API keys (they have shared ~30 test files generation quota):<p>KEY-1: tgai_jHOEgOfpMJ_mrtNgSQ6iKKKXFm1RQ7FJOkI0a7LJiWg<p>KEY-2: tgai_NlSZN-4yRYZ15g5SAbDb0V0DRMfVw-bcEIOuzbycip0<p>KEY-3: tgai_kiiSIikrBZothZYqQ76V6zNbb2Qv-o6qiZjYZjeaczc<p>KEY-4: tgai_JBfSV_4w-87bZHpJYX0zLQ8kJfFrzas4dzj0vu31K5E<p>Would love your honest feedback where this could go next, and on which setups it failed, how it failed, it has quite verbose debug output at this stage!

[Other] Show HN: Free and local browser tool for designing gear models for 3D printing Just build a local tool for designing gears that kinda looks and works nice

[Other] Mock APIs that update instantly — no restart, ever. Native desktop mock server that updates endpoints while running — no restart needed. Key features: → Live endpoint editing on running servers → Visual state machine for multi-step API flows → WebSocket, SSE support (mock ChatGPT-style streaming) → API recording — capture real responses, auto-create mocks → Chaos engineering — inject latency, random failures → 100% localhost, no cloud, privacy-first -> Performance: 166,000 req/sec Built with Tauri (Rust). Fast, lightweight, free.

[CLI Tool] Show HN: Shellock, a real-time CLI flag explainer for fish shell

[Database] PgX – Debug Postgres performance in the context of your application code

[Other] Show HN: SMTP Tunnel – A SOCKS5 proxy disguised as email traffic to bypass DPI A fast SOCKS5 proxy that tunnels your traffic through what looks like normal SMTP email, bypassing Deep Packet Inspection firewalls.<p>How it works: - Client runs a local SOCKS5 proxy (127.0.0.1:1080) - Traffic is sent to server disguised as SMTP (EHLO, STARTTLS, AUTH) - DPI sees legitimate email session, not a VPN&#x2F;proxy<p>Features: - One-liner install on any Linux VPS - Multi-user with per-user secrets and IP whitelists - Auto-generated client packages (just double-click to run) - Auto-reconnect on connection loss - Works with any app that supports SOCKS5<p>Tech: Python&#x2F;asyncio, TLS 1.2+, HMAC-SHA256 auth<p>GitHub: <a href="https:&#x2F;&#x2F;github.com&#x2F;x011&#x2F;smtp-tunnel-proxy" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;x011&#x2F;smtp-tunnel-proxy</a>

[IDE/Editor] Kiro is an agentic IDE that works alongside you from prototype to production.

[CLI Tool] Show HN: Bull.sh: Financial Modeling Agent CLI Built a free open source agentic CLI tool for financial modeling &amp; analysis. Hadn&#x27;t played around with real equity valuation modeling for awhile and wanted to build tooling to get myself back into the game.<p>Bull.sh lets you query &amp; store 10-Qs, 10-K in a local vector store to chat with them, build investment thesis from scratch or build full framework models through the CLI to export into excel.<p>It&#x27;s open source, just requires your own Anthropic API key and (optionally) AlphaVantage Free API key if you want save some tokens from scraping. Feel free to play around with it.<p>Some ideas I have for features (amongst improvements to the existing orchestration &amp; valuation frameworks):<p>1. Bull vs. Bear Agent Debate<p>Spawn two adversarial agents: one argues the bull case, one argues the bear case. They critique each other&#x27;s assumptions, then a moderator agent synthesizes a balanced thesis. Surface the strongest counterarguments automatically.<p>2. Earnings Call Analyzer<p>Auto-fetch earnings call transcripts (or transcribe audio), detect management tone shifts vs. prior quarters, extract forward guidance, flag hedging language (&quot;we believe&quot;, &quot;challenging environment&quot;). Compare CEO sentiment to online &amp; social sentiment.<p>3. Supply Chain Knowledge Graph<p>Parse 10-K supplier&#x2F;customer disclosures + news to build a graph of company relationships. Visualize dependencies, detect concentration risk, propagate shocks (&quot;if TSMC goes down, who&#x27;s exposed?&quot;). Use Neo4j or networkx.<p>4. Real-time 8-K Alert System<p>Monitor SEC EDGAR for new 8-K filings, classify by materiality (executive departure, M&amp;A, guidance change), push alerts via webhook&#x2F;Slack&#x2F;email. Let users set watchlists and filter by event type.<p>5. Thesis Backtester<p>Save thesis snapshots with timestamps. When the stock moves ±20%, resurface the original thesis and score which predictions were right&#x2F;wrong. Build a track record dashboard showing analyst accuracy over time.

[CLI Tool] Show HN: CLI for internet speed test via Cloudflare with optional TUI I&#x27;ve been having a lot of issues with my upload speed and wanted a cli tool to run in a cron job and couldn&#x27;t quite find one to suit my needs. Sharing here in case others find it useful.

[CLI Tool] Show HN: Stash – Sync Markdown Files with Apple Notes via CLI

[Other] Show HN: Repogen – a static site generator for package repositories Hi HN,<p>Package repositories don&#x27;t need to be complicated. They&#x27;re just static files: metadata indexes and the packages themselves. Yet somehow hosting your own feels like you need dedicated infrastructure and deep knowledge of obscure tooling.<p>repogen is an SSG for package repos. Point it at your .deb&#x2F;.rpm&#x2F;.apk files, it generates the static structure, you upload to S3 or any web host. Done. $0.02&#x2F;month to host packages for your whole team.<p>It supports Debian, RPM, Alpine, Pacman, and Homebrew. Has incremental mode for updating repos without redownloading everything. Handles signing. Very alpha, but it works. Would love to get feedback!

[Other] A collaborative list of public APIs for developers

[CLI Tool] Show HN: mcpc – Universal command-line client for Model Context Protocol (MCP)

[Other] High-performance header-only container library for C++23 on x86-64

[CLI Tool] Show HN: ccrider - Search and Resume Your Claude Code Sessions – TUI / MCP / CLI I built a tool that stores your full Claude Code history to let you easily find and resume sessions. It has TUI, CLI and MCP interfaces. It&#x27;s a single Go binary, and the session history is synced to SQLite each time you use it.<p>Default mode is the TUI with a session browser and full-text search. Once a session is selected you can browse and search within it, resume it or export to markdown.<p>The MCP server provides tools to let Claude search back through the session for pre-compact context or pull from prior sessions. I use this constantly.<p>I&#x27;ve seen elaborate continuity systems to give Claude Code access to history but this simple approach has been very effective.<p>Installation:<p>macOS: brew install neilberkman&#x2F;tap&#x2F;ccrider<p>Linux&#x2F;other: git clone <a href="https:&#x2F;&#x2F;github.com&#x2F;neilberkman&#x2F;ccrider" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;neilberkman&#x2F;ccrider</a> &amp;&amp; cd ccrider &amp;&amp; go build<p>MCP server: claude mcp add --scope user ccrider $(which ccrider) serve-mcp<p>Source: <a href="https:&#x2F;&#x2F;github.com&#x2F;neilberkman&#x2F;ccrider" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;neilberkman&#x2F;ccrider</a>

[Testing] Show HN: VaultSandbox – Test your real MailGun/SES/etc. integration I&#x27;ve spent the last few months working on something I wish I&#x27;d had years ago. I kept running into the same issue: CI green, production mail broken. TLS handshake failures, DKIM alignment mismatches, SPF soft-fails ... the stuff that only surfaces when real mail servers are involved. Most test tools (Mailpit, MailHog) are catch-alls. They confirm &quot;an email was sent&quot; but don&#x27;t validate the protocol. They also aren&#x27;t designed for network-exposed environments: no auth, unprotected Web UI, easy to enumerate messages.<p>VaultSandbox is my attempt at fixing that. It&#x27;s a self-hosted SMTP gateway (AGPLv3) that validates SPF, DKIM, DMARC, and rDNS on every incoming message. You keep your production email provider (Postmark, SendGrid, SES) in tests and you just change the recipient domain. No mocking, no config changes. There are client SDKs (Node, Python, Go, Java, .NET), plus a Web UI and a CLI for manual testing.<p>Some technical details:<p>Deterministic Tests Instead of polling or sleep loops, the SDKs use Server-Sent Events (SSE) so test assertions trigger the moment the mail hits the gateway.<p>Minimal infrastructure footprint Built with NestJS and Angular, with no external database dependency to keep the container footprint small and easier to reason about.<p>Post-Quantum Encryption I use ML-KEM-768 for the encryption layer. Incoming mail is encrypted immediately using a client-generated public key and the plaintext is discarded. The server only ever stores encrypted message data and cannot decrypt it. I chose PQ because I wanted to build something I wouldn&#x27;t have to revisit in five years. If it handles large PQ keys reliably, everything else is easy.<p>Quick start: <a href="https:&#x2F;&#x2F;vaultsandbox.dev&#x2F;getting-started&#x2F;quickstart&#x2F;" rel="nofollow">https:&#x2F;&#x2F;vaultsandbox.dev&#x2F;getting-started&#x2F;quickstart&#x2F;</a><p>Site: <a href="https:&#x2F;&#x2F;vaultsandbox.com" rel="nofollow">https:&#x2F;&#x2F;vaultsandbox.com</a><p>I&#x27;d love feedback, especially on whether AGPLv3 would be a blocker for something you&#x27;d self-host in dev.

[Other] Show HN: Mantic.sh – A structural code search engine for AI agents Author here! Some context: I published this 48 hours ago and it was auto-listed on MCPMarket (the MCP tools directory). Got 700+ organic downloads with zero marketing—developers were actively searching for exactly this solution.<p>The &quot;Git Accelerator&quot; optimization story:<p>Initially used a file walker that took 6.6s on Chromium. Profiling showed 90% was filesystem I&#x2F;O. The fix: git ls-files returns 480k paths in ~200ms. Added smart heuristics for untracked files (only scan dirs &lt;50k files), bringing total to 0.46s.<p>Why this matters: Agents can&#x27;t wait 10 seconds for search. Sub-500ms makes it feel instant, changing how they explore codebases.<p>Installation:<p><pre><code> Cursor: npx mantic.sh@latest VS Code: npx mantic.sh@latest CLI: npm i -g mantic.sh </code></pre> Limitations: Mantic is optimized for precise queries (&quot;find stripe webhook&quot;) where structure matters. For fuzzy exploratory search, traditional embeddings may still be better. Curious if HN has ideas for hybrid approaches.<p>Happy to answer questions!