JAR — Join-Accumulate Refine

JAR is a blockchain protocol based on JAM (Join-Accumulate Machine). This monorepo contains both the formal specification and a full node implementation.

PVM Recompiler

Grey's x86-64 JIT recompiler outperforms polkavm v0.32.0 on all workloads with pipeline gas metering. Benchmarks include full compile+execute each iteration (realistic JAM model where each work-package is compiled fresh):

Benchmark	Grey Recompiler	PolkaVM Generic	PolkaVM Linux	Grey vs best PolkaVM
Fibonacci (1M iter)	416 µs	429 µs	414 µs	1.00x
Host calls (100K ecalli)	834 µs	3,177 µs	30,164 µs	3.8x faster
Sort (500 elements)	434 µs	463 µs	452 µs	1.04x faster
Ecrecover (secp256k1)	2,078 µs	3,122 µs	2,958 µs	1.42x faster

Key optimizations: per-basic-block pipeline gas simulation, peephole instruction fusion, mprotect+SIGSEGV memory bounds checking (zero-instruction hot path), register-mapped PVM state, cold OOG/fault stubs.

Repository Structure

Directory	Description
spec/	Lean 4 formal specification — executable, machine-checked, tested against conformance vectors
grey/	Grey — Rust protocol node implementation

Genesis — Proof of Intelligence

JAR uses a Proof-of-Intelligence model for its genesis token distribution. Every merged PR is scored on difficulty, novelty, and design quality by ranked comparison against past commits. See GENESIS.md for the full protocol design.

Quick Start

Spec (Lean 4)

cd spec
cd crypto-ffi && cargo build --release && cd ..
lake build
make test

Grey (Rust)

cd grey
cargo test --workspace

License

Apache-2.0