[FINAL REPORT] Arbitrum Native Precompile & Tx-Type Support for Local Testing

DAO Programs & Initiatives Domain Allocator Offerings (prev Questbook)
1

Project Summary

We delivered practical local-dev support for Arbitrum precompiles (ArbSys, ArbGasInfo) so teams can exercise Arbitrum-specific logic in Hardhat and Foundry without bouncing to testnets. Across Milestones 1–5 we stood up the public repo and probes, implemented the core local approach, added a validation harness with example ERC-20/721 flows, launched public docs and onboarding, and ran a support window with fixes, compatibility tracking, and a real-world demo dapp that uses these precompiles in production-style workflows. (Project Website) (GitHub)

Major Highlights

Milestone Reports

01 — Research & Compatibility Mapping (Completed)

What we shipped

  • Public repository, initial probes (Hardhat/Foundry), and early compatibility notes.

  • Short walkthrough video summarizing scope and setup.

Links

02 — Core Patch Development (Completed)

What we shipped

  • Core local approach: Hardhat shim path and an Anvil variant enabling local calls to ArbSys/ArbGasInfo, with implementation notes in docs.

Links

03 — Test Suite & Validation Scripts (Completed)

What we shipped

  • Automated checks and example ERC-20/721 flows to validate parity between patched localnets and on-chain behavior.

  • Quick overview and full walkthrough videos.

Links

04 — Documentation & Developer Onboarding (Completed)

What we shipped

  • Public docs site with consolidated guides, updated GitHub docs, and an onboarding video set.

Links

05 — Maintenance & Ecosystem Support (Completed)

What we shipped

  • Monthly public update documenting issues triaged/fixed and compatibility notes, plus a roadmap.

  • A production-style demo dapp that uses ArbSys for block-timed vesting and ArbGasInfo for L1 gas reimbursement, with a short demo video.

Links

Conclusion

Milestones 1–5 delivered the intended outcome: fast, reproducible local workflows for Arbitrum precompiles with clear docs, validation, and a real-world demo. We’ll keep maintaining the repo, tracking toolchain changes, and helping teams adopt the patches through public updates and community support. For feedback, issues, or contributions, use the discussions and repo links above. (GitHub) .

Thank you.

2

Ox-rollup Maintenance Update – January–February 2026 (Milestone 6)

Summary

This maintenance window focused on improving local parity for ArbGasInfo behavior, expanding Anvil local emulation coverage, strengthening CI reliability, and improving developer ergonomics for comparing local vs remote gas and pricing behavior.

Discussion update:
https://github.com/Supercoolkayy/Ox-rollup/discussions/17

Issues addressed (triaged and fixed this cycle)

  1. Issue #11 — ArbGasInfo tuple + legacy L1 cost logic mismatch
    Aligned tuple/field behavior with expected Nitro-style outputs and removed legacy assumptions that caused incorrect local L1 cost interpretation.
    https://github.com/Supercoolkayy/Ox-rollup/issues/11

  2. Issue #12 — Missing selectors for Nitro-style gas accounting and pricing
    Added support for commonly used selectors so local runs don’t revert when apps query gas parameters or pricing constraints, including:
    getGasAccountingParams(), getGasPricingConstraints(), getL1BaseFeeEstimate(), getMaxTxGasLimit().
    https://github.com/Supercoolkayy/Ox-rollup/issues/12

  3. Issue #13 — Granular reseeding for arb:reseed-shims
    Made reseeding more modular by allowing updates in separate buckets, so developers can refresh specific parameters without overwriting unrelated shim state.
    https://github.com/Supercoolkayy/Ox-rollup/issues/13

  4. Issue #14 — Precompile gas cost parity
    Replaced the previous linear gas-cost approximation with fixed costs intended to reduce drift in local profiling.
    https://github.com/Supercoolkayy/Ox-rollup/issues/14

  5. Issue #15 — Better calldata compression approximation for L1 fee estimation
    Introduced a more realistic approximation for calldata compression so local L1 fee estimates better reflect what developers see on remote networks.
    https://github.com/Supercoolkayy/Ox-rollup/issues/15

  6. Issue #16 — Developer experience improvements (arb:gas-info)
    Improved the structure and readability of arb:gas-info output so it’s easier to compare local values against remote values and spot discrepancies quickly.
    https://github.com/Supercoolkayy/Ox-rollup/issues/16

Changelog and tagged release

Changelog:
https://github.com/Supercoolkayy/Ox-rollup/blob/main/CHANGELOG/CHANGELOG.md

Releases:
https://github.com/Supercoolkayy/Ox-rollup/releases

Next

We’ll continue tracking Nitro/ArbOS behavior changes that impact local parity, respond to new bug reports, and expand/adjust parity probes where needed to keep developer workflows stable.