Systems Thinking Lab: Free Engineering Tools
Free tools from Systems Thinking Lab, installable as
Claude Code plugins or, for other coding agents, as
Agent Skills (see Install below). Scaffold is the workflow; design-with-blocks and
review-with-blocks apply the seven building blocks (see The tools and The framework below).
Install
Add the marketplace once:
/plugin marketplace add kayashaolu/systemthinkinglab
Then install any tool:
/plugin install design-with-blocks@systemthinkinglab
/plugin install review-with-blocks@systemthinkinglab
/plugin install scaffold@systemthinkinglab
Updates later are just /plugin marketplace update systemthinkinglab.
For agents other than Claude Code:
npx skills add kayashaolu/systemthinkinglab --skill design-with-blocks
npx skills add kayashaolu/systemthinkinglab --skill review-with-blocks
npx skills add kayashaolu/systemthinkinglab --skill scaffold
Each skill lands in your project's .agents/skills/<name>/ as an Agent Skill; they are built and tested in Claude Code.
The tools
| Plugin | What it does |
|---|
| design-with-blocks | Design an app using the 7 Universal Building Blocks: describe it in plain English, decompose features into blocks, get per-block technology recommendations, and output a buildable design doc. |
| review-with-blocks | Review a finished system design against the 7 building blocks and the non-functional "-ilities": decompose it, flag wrong/missing/over-engineered blocks, rate each load-bearing -ility (holds / at-risk / gap) with its tradeoff, and surface the questions a senior would ask. |
| scaffold | A plan-first developer workflow, run by an AI mentor: it predicts before it builds, keeps a compounding wiki of your codebase, and holds an honest ledger of what you've demonstrated you know, in craft or direction mode. |
All three are free, open source (Apache-2.0), and installable by anyone. Together they cover the arc design → build → review: design-with-blocks plans the architecture, scaffold runs the plan-first workflow while you build it, and review-with-blocks judges the result. All three use the seven building blocks, free to read at systemthinkinglab.ai/learn.
The framework
Every system, from Instagram to Stripe, is built from the same seven primitives:
Service, Worker, Key-Value Store, File Store, Queue, Relational Database,
Vector Database; plus three external entities: User, External Service, Time.
That vocabulary is the intellectual work of Kay Ashaolu, founder of Systems
Thinking Lab. If you want pattern literacy, the ability to design any future
system without a tool, you can learn the 7 building blocks for free at
systemthinkinglab.ai/learn.
