First PCD Circuit: A Minimal Walkthrough

Your First PCD Circuit — In Five Minutes

PCD — Printed Circuit Description — is a programming language where every program is a verifiable circuit. Other languages describe instructions. PCD describes connections between BRIK64 monomers — just like a PCB describes physical connections between components. Every PCD program can be measured, verified, and certified before it ever runs.

In the next five minutes, you will write your first PCD circuit, run it, compile it to JavaScript and Python, and verify its certification. No setup wizards. No dependency hell. One binary, one command.

Step 1: Install brikc

The BRIK64 compiler is a single binary. One command. No package managers, no dependencies, no configuration files:

curl -L https://brik64.dev/install | sh

That installs brikc to ~/.brik/bin and adds it to your PATH. Verify it works:

brikc --version

Step 2: Create hello.pcd Create a file called hello.pcd. This is a factorial circuit — the kind of thing other languages need 10 lines and a prayer for:

// A factorial circuit
// Takes input n (8-bit unsigned), computes factorial
// Outputs result as 16-bit value
// Every operation is a verified BRIK64 monomer

This circuit takes an 8-bit unsigned integer n, computes its factorial, and outputs a 16-bit result. Every single operation in that pipeline is one of BRIK64's 128 mathematically certified monomers. Not a library call. Not a runtime function. A verified atomic operation.

Step 3: Run It

Execute the circuit. No build step. No compilation wait. Just run:

brikc run hello.pcd
#
Input: n = 6
# Output: 720

The default input is n = 6, and 6! = 720. The circuit produces the correct result. But here is the difference from every other language: brikc automatically verifies the computation during execution. It does not just run your code — it proves it.

Step 4: Compile to JavaScript

Here is where it gets interesting. PCD circuits compile to 14 different target languages. Start with JavaScript:

brikc build hello.pcd -t javascript

This generates output/hello.js. Run it with Node:

node output/hello.js
# Output: 720

Same input, same output. Not approximately the same. Exactly the same. The compiled JavaScript preserves every verification guarantee from the original PCD circuit.

Step 5: Compile to Python

Want Python instead? Same command, different flag:

brikc build hello.pcd -t python

This generates output/hello.py. Same verified result. Same guarantees. One circuit, any language. That is 14 targets from a single source of truth — Rust, JavaScript, TypeScript, Python, C, C++, Go, COBOL, PHP, Java, Swift, WebAssembly, BIR bytecode, and native x86-64.

Step 6: Check Certification

Now for the part that Few public tools in this category can do — verify the circuit's mathematical certification:

brikc check hello.pcd Circuit: factorial Monomers: 3 operations Composition: sequential TCE: 7 metrics evaluated
───────────────────────── Φc = 1 ✓ CERTIFIED

What Does Phi C = 1 Mean? Phi C = 1 means the circuit is closed — every input maps deterministically to an output, with zero information leakage. Not for some inputs. For all inputs within the declared domain. Your first circuit is not just tested. It is certified. Go build something.