RewriteBrief
A decision-support workspace for engineering leaders evaluating large language, framework, or platform rewrites — models the cost, surfaces the parity gap, and produces a board-ready memo.
CTOs, VPs of Engineering, and principal engineers facing a 'rewrite or refactor' decision
- Cost modeler that takes your codebase size, team headcount, and target stack and outputs a 12-month cost-and-timeline projection with three scenarios (full rewrite, strangler, refactor)
- Parity tracker that lets the team tag features as 'parity,' 'gap,' or 'improved' across the old and new stacks, with a burn-down chart leadership can read
- Risk register auto-populated from public postmortems of similar rewrites (Rust-to-Zig, Scala-to-Kotlin, etc.) so you don't repeat them
- One-click board memo generator that turns the live tracker into a one-pager with status, spend, and ask
The Roc team's 487-day Rust-to-Zig rewrite and Bun's 11-day reverse rewrite both got serious HN attention, and the post explicitly calls out how different rewrites compare — engineering leaders are hungry for frameworks to think about this.
Multiple active resources confirm real interest: SE Radio dedicated an episode (#656) to rewrite vs refactor, HN thread hit 227 points/126 comments, and several CTO-targeted blogs publish decision frameworks — but most demand manifests as long-form content/guides rather than dedicated SaaS pull.SE Radio 656: Ivett Ördög on Rewrite versus Refactor ↗Roc rewrites the compiler in Zig | Hacker News ↗
Direct overlap exists: 'The Art of CTO' already ships a free Rewrite vs Refactor tool with risk modeling and strangler-fig strategy, and CTO Framework / CTO Toolkit offer adjacent decision tooling — the parity-gap and board-memo angle is differentiated but the market is not wide-open.Rewrite vs Refactor | The Art of CTO ↗CTO Framework — Technical Leadership Playbooks & Tools ↗
CTO-targeted SaaS does monetize (Art of CTO runs 60+ interactive tools and exposes 'Fractional CTO Pricing'), but a single-purpose rewrite-decision tool is episodic — buyers will tolerate maybe $20–80/seat/mo at best and many will use the free alternatives already available.The Art of CTO — Decisions, Frameworks, and Tools for Technology Leaders ↗Rewrite vs Refactor: CTO Decision Framework at Scale ↗
Rewrites are perennial and AI-assisted coding is accelerating code-migration projects (Roc/Bun highlighted), but each prospect only buys once per multi-year rewrite cycle — usage is spike-driven and the category won't compound like dev-tooling daily-use products.How Our Rust-to-Zig Rewrite is Going ↗Roc & Zig: A Compiler Rewrite Story ↗
A first version is buildable as templates + cost/spreadsheet logic + memo generator, but 'parity gap' modeling is genuinely hard — it requires ingestion of real codebases/tests, which is a non-trivial ML/analysis lift to do well.Rewrite vs Refactor Decision Framework for CTOs | The Art of CTO ↗