Pack · #120 trending skills repo · ↗ +191 stars this week
Simcraft
dotslashsimran/simcraft
my claude skills for everyday work
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- 367
- This week
- +191
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- 25
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- 0
- Skills inside
- 24
Get started
Install the skills
npx skills add dotslashsimran/simcraftInstalls into Claude Code, Codex, Cursor, OpenCode and the other agents it finds on your machine.
git clone --depth 1 https://github.com/dotslashsimran/simcraft.git /tmp/simcraft
cp -r /tmp/simcraft ~/.claude/skills/simcraftClaude Code reads ~/.claude/skills/ (or .claude/skills/ in a project). Other agents read the same SKILL.md format from their own skills folder.
Inside this repo
24 skills
api-design-reviewReview the design of an API surface, meaning an HTTP API (OpenAPI spec or route code), an SDK's public classes and functions, or a CLI. Checks naming and consistency, resource modelling, error design (stable codes, RFC 9457 problem details, request ids), versioning and breaking changes, pagination,
skills/coding/api-design-reviewbenchmark-honestlyBuild benchmarks that survive scrutiny and catch the classic lies (dead code elimination, lazy results, constant folding, warm caches, coordinated omission, averages hiding GC pauses, unequal work, noisy machines). Defines the question first, controls and discloses the environment, uses warmups, intskills/coding/benchmark-honestlybisect-anythingFind the exact commit (or dependency version, config value, or input) that caused a regression by turning it into an automatic pass/fail check and running git bisect run in a separate worktree, then shrink the bad commit to the hunk that matters and explain it. Handles failing tests, changed output,skills/coding/bisect-anythingcodebase-mapUnderstand an unfamiliar codebase fast, the way senior engineers do. Reads the orientation signals (README, manifests, CI, Dockerfiles, routes, migrations), mines git history for hotspots, hidden coupling and ownership, builds the import graph to find layers, cycles, load-bearing and dead code, thenskills/coding/codebase-mapdx-auditAudit the developer experience of a developer tool (SDK, API, CLI, framework) by trying it exactly like a brand-new developer, from the official docs only, in a fresh empty environment. Logs every step with timestamps and friction tags, measures time to first success, steps, page switches, errors anskills/coding/dx-auditflaky-test-killerFind why a test is flaky and fix the root cause, never by adding retries, sleeps or bigger timeouts. Measures the flake rate with a confidence interval, runs the test under stressors (random order, timezone, fake clock at month end or DST, CPU load, fresh temp dir, low file limits), bisects for the skills/coding/flaky-test-killersecurity-threat-modelThreat-model the user's own app from its real code. Draws the data flow (actors, trust boundaries, data stores, external services) as a Mermaid diagram, finds threats per element with STRIDE, ranks them by likelihood times impact, then proves each top risk with a local failing test, fixes it, and keskills/coding/security-threat-modelbrand-kitLearn a company's brand design from its live website (colours, fonts with the real font files, logo, button and card shapes, texture, image style) and save it as a reusable kit that vox-explainer and image-gen apply automatically. Use FIRST, before any brand or sponsored video, sticker, graphic or askills/design/brand-kitimage-genGenerate images with the user's own API keys (Google Gemini "Nano Banana" or OpenAI gpt-image). Use when asked to generate, create or make an image, illustration, icon, cut-out, sticker, thumbnail, texture, mockup or visual asset, to edit an image, or to make several images that stay consistent (samskills/design/image-genfrom-scratchLearn how something really works by building the smallest working version of it from scratch, Karpathy style, one small step at a time, with the user predicting what each step will do before running it. Works for ML and AI ideas (attention, tokenizers, backprop, RAG, agents), systems (a database, anskills/learning/from-scratchpaper-to-runnableTurn a research paper (arXiv id, arXiv URL or local PDF) into the smallest honest working implementation of its core idea, checked with a sanity ladder and a toy reproduction of the paper's main result, plus plots or an animation of what happens inside and a short explainer. Use when the user says "skills/learning/paper-to-runnablesystem-design-from-scratchDesign a backend or distributed system by building a tiny but real working version of it, proving its properties with invariant tests, a load test (throughput and p50/p95/p99 latency) and fault injection (crashed nodes, dropped or delayed messages, partitions, clock skew, full disks), then writing askills/learning/system-design-from-scratchteach-backFind out what the user actually understands about a topic by having them explain it back (the Feynman technique), then probe the gaps one question at a time and end with a one-page cheat sheet and spaced review questions. Works for anything they are studying or have just read, watched or built: a paskills/learning/teach-backnext-stepTurn a big, messy goal or a brain dump into one clear next action at a time, for people who freeze in front of long to-do lists (ADHD-friendly). Asks one question at a time, keeps a small plan file, and only ever shows the single next step plus how long it takes. Use when the user says "I don't knowskills/planning/next-stepskill-routerDecide which installed skill, or which chain of two or three skills, fits a task before starting it, and run them in the right order with each one's output feeding the next. Works with any set of skills, because it reads every installed skill's description at run time. Use when a task is big or vaguskills/planning/skill-routervideo-scriptWrite a short talking-head, explainer or product demo video script (30 seconds to 3 minutes) that sounds like the creator, not like AI. Starts from their own voice-note ramble, builds one question, one story, one lesson, puts the stakes in the first line, sizes it to the target length, and lists eveskills/planning/video-scriptclean-audioClean up voice audio in a video: rumble, electrical hum, background noise and hiss, muddy or harsh tone, sharp S sounds, uneven volume, and loudness for YouTube/Instagram/TikTok. Measures the audio first, picks the strongest cleanup that doesn't make the words less clear, and keeps lip sync exact. Uskills/video/clean-audiocode-loopMake a seamless, perfectly looping generative video in code, from a three.js scene or a raw GLSL fragment shader, rendered frame-perfect with jittered anti-aliasing and motion blur, then checked for a visible seam, freezing and blinking. Use when asked for a "seamless loop", a "perfect loop", "generskills/video/code-loopperspective-illusionMake a looping illustrated 3D video in the Japanese perspective-illusion style (e.g. @garments__) of any place, such as a street, crossing, station, shop aisle, room, park or rooftop. A clean line-art scene squashed flat by a telephoto lens opens into deep perspective with dolly zooms, swings round skills/video/perspective-illusionrepo-timelapseTurn a git repo's history into a video of the project growing. Files appear as a living treemap coloured by language that grows with the code, glows when touched and fades on delete, with a date, a lines-of-code counter, commit messages typing in as captions and an activity sparkline. 16:9 or 9:16, skills/video/repo-timelapsereverse-engineer-videoBreak down a reference or viral video clip so it can be remade. Finds every cut and dissolve, times each shot, measures pacing, works out the camera move in each shot (static, pan, tilt, zoom or push in, roll, handheld shake, with speed), finds beats and loudness jumps and checks whether the cuts laskills/video/reverse-engineer-videorough-cutTrim the fat from raw talking footage. Turns raw video into a tight first cut by removing dead air, ums and uhs, stutters, false starts and bad takes (keeping the last good take), then checks the result by listening to it again. Use when the user says "rough cut", "first cut", "trim the fat", "cut tskills/video/rough-cutscripted-screencastTurn a browser product demo written as a script (click, type, hover, scroll, zoom, caption) into a polished Screen Studio style recording. You get a smooth human-like cursor, click ripples, automatic zoom on small targets, typing at human speed, a padded background with a rounded window frame, burneskills/video/scripted-screencastvox-explainerMake Vox-style explainer graphics or a full faceless explainer video, in the user's chosen "style C" (navy and red colour blocks, torn cream paper cards, condensed uppercase headlines, serif quotes, yellow highlighter, black mono label strips, light grain). Every beat, highlight and list item is timskills/video/vox-explainerDocumentation
README
simcraft
Skills that teach Claude how to do hard things well.
24 skills for Claude Code, built from real projects, with the parts tutorials skip.
Install · Video · Engineering · Learning · Design · Planning
Each skill is a folder with a SKILL.md: the method, the judgement calls, and real, tested scripts for one kind of work. Claude Code loads the right one when your request matches. You don't call them by name, you just ask.
What makes them different: every skill covers what breaks, how to check the result, and how to tell good from good enough.
Install
git clone https://github.com/dotslashsimran/simcraft ~/simcraft
mkdir -p ~/.claude/skills
for s in ~/simcraft/skills/*/*/; do ln -s "${s%/}" ~/.claude/skills/; done
cd ~/simcraft && npm i
Then open Claude Code and ask for something, like "make a perspective-illusion loop of a rainy night street".
More setup details
- Claude Code finds skills one folder deep, so the loop links each one into
~/.claude/skills. The categories are only for browsing. To install a single skill, link just that folder. - A few skills have a one-time setup script in their folder (for example
setup.shfor Whisper in rough-cut). Each SKILL.md says so at the top. - Needs: Python 3.9+, Node 18+ (for skills that drive a browser or render video), and ffmpeg on your PATH or set as
FFMPEG=/path/to/ffmpeg. - API keys (only image-gen uses them) are read from your environment or
~/.config/simcraft/keys.env. They never go in the repo.
Skills
🎬 Video
| Skill | What it does |
|---|---|
| perspective-illusion | Illustrated 3D loops in the Japanese perspective-illusion style: flat scenes that open into depth. |
| code-loop | Any three.js scene or shader rendered as a seamless loop, checked for seams, freezes and blinks. |
| reverse-engineer-video | Hand it a viral clip, get a remake plan: every cut, camera move and beat. |
| scripted-screencast | Product demos written as a script and rendered frame-perfect. No retakes. |
| repo-timelapse | Your git history as a video of the project growing. |
| rough-cut | Raw talking footage to a tight first cut: pauses, ums and retakes removed. |
| clean-audio | Voice cleanup that measures first, then keeps every word clear. |
| vox-explainer | Vox-style explainer graphics timed word by word to a voiceover. |
🧑💻 Engineering
| Skill | What it does |
|---|---|
| codebase-map | Learn an unfamiliar repo fast by tracing one real request end to end. |
| bisect-anything | Find the exact commit behind any regression, then the exact lines. |
| flaky-test-killer | Fix why a test is flaky, never with retries, and prove the fix. |
| benchmark-honestly | Benchmarks that survive scrutiny, with confidence intervals. |
| api-design-review | Review an API, SDK or CLI, and catch breaking changes. |
| security-threat-model | Threat-model your own app from its real code, LLM apps included. |
| dx-audit | Try a developer tool like a brand-new user and time it to first success. |
🧠 Learning
| Skill | What it does |
|---|---|
| paper-to-runnable | A research paper turned into the smallest honest implementation of its idea. |
| system-design-from-scratch | Build a tiny real system, load-test it, break it, write up the trade-offs. |
| from-scratch | Learn anything by building the smallest version of it, one step at a time. |
| teach-back | You explain it, Claude finds the gaps, you get a one-page cheat sheet. |
🎨 Design
| Skill | What it does |
|---|---|
| image-gen | Images with your own Gemini or OpenAI key, consistent across a set. |
| brand-kit | Learn a brand from its live site into a kit the other skills apply. |
🧭 Planning
| Skill | What it does |
|---|---|
| skill-router | Picks the right skill for a task, or a chain of two or three. |
| next-step | A big messy goal turned into one clear next action at a time. |
| video-script | Short video scripts that sound like you, built from your own ramble. |
Chains that work well
skill-router builds these on its own when a task has stages.
| Start with | Then |
|---|---|
| A viral clip | reverse-engineer-video → code-loop or perspective-illusion |
| A research paper | paper-to-runnable → vox-explainer |
| A new SDK | dx-audit → scripted-screencast |
| "It got slower" | benchmark-honestly → bisect-anything |
| A new job | codebase-map → flaky-test-killer |
| Raw footage | rough-cut → clean-audio |
Credits
image-gen was inspired by adamd9/skill-image-gen, and vox-explainer by Charlie Hills' vox-animation skill (both MIT). Everything here is written from scratch.
License
MIT © Simran Sachdeva