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Graft v1.1: Parallel Execution and Foreach Loops

3 min read
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What is Graft?

Graft is a graph-native language that compiles .gft files to Claude Code harness structures. It eliminates token waste in multi-agent AI pipelines by providing typed schemas and edge transforms at the language level.

What v1.1 Adds

Two flow control primitives that enable real-world multi-agent patterns:

Parallel Execution

Run nodes concurrently when they have no data dependencies:

graph Review(input: CodeDiff, output: Report, budget: 20k) {
  parallel {
    SecurityReviewer
    PerformanceReviewer
    StyleReviewer
  }
  -> Aggregator -> done
}

The compiler estimates parallel block cost as the sum of all branches (worst case: all run to budget).

Foreach Loops

Iterate over list outputs with a configurable cap:

graph BatchProcess(input: TaskList, output: Results, budget: 50k) {
  Splitter
  -> foreach(Splitter.output.tasks as task, max_iterations: 10) {
    Processor -> Validator
  }
  -> Collector -> done
}

Token estimation: best case = 1x iteration, worst case = Nx iterations.

Multi-Field Select

select(a, b, c) keeps multiple fields in a single transform — no longer need chained select calls.

Process Evolution: Adaptive Adversarial Loop

v1.1 introduced key improvements to the debate process:

  • Benchmark-first development — define .gft test files before writing code
  • Complexity-based agent scaling — 4 agents for complex tasks, fewer for simple ones
  • Skeptic-only review — A3-Skeptic catches everything, full 4-agent review is overhead

A Bug in the Benchmark File

The debate found a bug not in the compiler, but in parallel_flow.gft — SecurityReviewer was listed both before and inside a parallel block. A3-Skeptic spotted the duplicate.

Forced Dissenter: Recursive vs Flat FlowNode

A1-Architect (forced dissenter) initially argued for flat FlowNode representation. Self-reversed after cross-critique: "recursive FlowNode has stronger code-reuse argument." 3-to-1 vote for recursive FlowNode discriminated union:

export type FlowNode =
  | { kind: 'node'; name: string }
  | { kind: 'parallel'; branches: FlowNode[][] }
  | { kind: 'foreach'; source: ContextRef; variable: string;
      maxIterations: number; body: FlowNode[] };

A3 also caught a foreach 3-part path issue (source context, field, and variable all need tracking).

Stats

| Metric | Value | |--------|-------| | New tests | 25 (135 total) | | New benchmarks | 2 (16 total) | | New keywords | 4 (parallel, foreach, as, max_iterations) | | Ratchet-locked decisions | 58 total |

Try It

git clone https://github.com/JSLEEKR/graft.git
cd graft && npm install && npm run build
node dist/index.js compile examples/parallel_flow.gft --out-dir ./output

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