Compatibility
The design follows CRuby’s builtin-validation behavior while adapting the mechanism to JRuby’s different concurrency model.
Troy Mallory’s contribution is included in JRuby 10.1+.
Co-founder Troy Mallory’s builtin-tracking architecture was merged upstream through PR 9174, then expanded across JRuby’s runtime fast paths by maintainer Charles Oliver Nutter.
Shipped upstreamCore runtime infrastructurePublic evidence
JRuby PR 9174
Builtin tracking in the JRuby runtime
JRuby maintainers reviewed and merged PR 9174, expanded the implementation and included it in the release line.
JRuby needed a CRuby-compatible way to determine whether a builtin method was still safe to use without sacrificing JRuby’s true parallelism. Troy designed a thread-local tracking system with lock-free reads, tested the approach in Kestowv OS, and opened the implementation upstream as CufeHaco.
Maintainer Charles Oliver Nutter merged and extended the contribution across core runtime fast paths. The release lineage carries that work into JRuby 10.1.0.0, and the credited implementation is present in the linked JRuby 10.1.1.0 source.
Upstream review and release history
The linked upstream records document independent adoption.
- Status
- Shipped upstream
- Runtime
- JRuby 10.1+
- Contributor
- Troy Mallory, CufeHaco
- Maintainer
- Charles Oliver Nutter
- Layer
- JRuby core runtime infrastructure
- Origin
- Author-reported Kestowv OS validation
Fast paths can verify the builtin before they trust it.
The architecture tracks builtin state per thread, preserves JRuby’s parallel execution model, and gives optimized runtime paths a low-overhead way to fall back when Ruby code replaces a builtin.
Parallelism
Thread-local state avoids turning a compatibility check into a global lock around a runtime built for true parallel work.
Integration
The maintainer expansion carried the mechanism beyond one patch and into the fast paths that need to know whether a builtin remains valid.
Author-reported validation
Reported builtin-validation timings
These figures come from the PR 9174 submission. They measure builtin-validation checks, not the complete Ruby operations.
15ns → 3nsInteger plus builtin check
18ns → 4nsString bracket builtin check
12ns → 3nsArray append builtin check
20ns → 5nsRange include builtin check
The PR author reported roughly 4x to 5x gains for these validation checks. Valen Systems hasn’t presented them as independent end-to-end benchmarks of the full Ruby methods.
Contribution and release chronology
The links below identify the author’s validation report, contribution, maintainer changes and released source.
- 01Kestowv validation
Troy reported testing the architecture in Kestowv OS before opening it upstream.
- 02CufeHaco contribution
PR 9174 introduced complete thread-local builtin tracking for JRuby.
- 03Maintainer review and merge
Charles Oliver Nutter merged the contribution into JRuby.
- 04Maintainer expansion
A follow-on commit explicitly credits PR 9174 and extends the mechanism across runtime integrations and fast paths.
- 05JRuby 10.1 release
The contribution is an ancestor of JRuby 10.1.0.0 and remains credited in the 10.1.1.0 source.
Inspect the public record.
The deployment claim is backed by the upstream pull request, merge history, maintainer expansion, release lineage, and current credited source.
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