Open-source fixes · Security and AI tooling · Technical strategy
I investigate reproducible software failures, build focused regressions, and work with maintainers to get fixes upstream. I also translate complex engineering work into clear, useful technical communication.
Proof-of-work case studies · Complete upstream record · LinkedIn
A short, evidence-led selection. Each link leads to the original upstream PR; detailed red/green case studies are in Open Source Fix Analysis.
| Project | Fix | Evidence |
|---|---|---|
| OpenAI Codex Security #1306 | Restored Vyper .vy coverage in scanning inventories and ranking |
Maintainer independently verified five red/green cases; 295 affected-module tests passed |
| Nethermind #14228 | Prevented cached JWTs being accepted past their explicit expiry | Deterministic expiry-boundary regression; merged upstream |
| Polygon Agent CLI #142 | Prevented x402-pay from broadcasting payments during dry runs |
Standard and Bazaar payment-path regressions; merged upstream |
| EthSystems Works #51 | Removed a reproducible rotortree snapshot panic at maximum tree depth |
Red/green regression, 180 all-feature tests; merged upstream |
| Promptfoo MCP Agent Provider #95 | Replaced fabricated token-usage estimates with measured OpenAI usage | Real-SDK loopback regressions; merged upstream |
Open Source Fix Analysis — Plain-English case studies linking the root cause, minimal patch, tests, review and merge evidence.
- GTM-Teardowns — Public, audit-first go-to-market and positioning teardowns.
- Web3 Security Library — Security education and tooling contributions from my time at Immunefi (commit history).
- Best-DeFi-Security-Practices — Reference collection of security practices for DeFi protocols.
Fixes merged, cherry-picked or otherwise incorporated upstream by project maintainers:
| Project | Impact | Change |
|---|---|---|
| blackrock/HOLA #69 | — | Corrected the documented Forrester benchmark so the README and getting-started examples match the repository implementation and reproduce the stated minimum. Added a regression comparing both documented objectives against the benchmark at five inputs; all 10 numerical comparisons fail before the fix and pass within 1e-12 after. Merged upstream as 55647c9 |
| openai/codex-security #1306 | Medium · security coverage | Added Vyper .vy sources to scan inventories and ranking paths so Vyper-only changes are not omitted before review-item generation. OpenAI maintainer independently verified all five new inventory/ranking regressions fail on the parent and pass with the fix; 295 affected-module tests passed with no blocking behaviour issues. Merged upstream as d327164 |
| openai/codex-security #1021 | Medium · security coverage | Added Solidity .sol files to diff scan inventories and rank inputs, with red/green coverage across repository, revision and local-patch modes |
| openai/codex-security #1020 | — | Required verification evidence before no_change remediation results are treated as resolved, with a regression proving evidence-free results fail closed |
| openai/openai-guardrails-js #148 | — | Fixed vector-store uploads for supported documents inside directories whose names contain dots. Three red/green regressions, 882 tests, multi-version CI and CodeQL passed |
| GoogleChrome/chromium-dashboard #6946 | — | Restored the “Draft Intent to Extend Experiment” email action when API-owner gates are active across normal launch, fast-track and deprecation processes. Added a regression covering all three definitions; merged as ca80064 and deployed in release #6950 |
| promptfoo/mcp-agent-provider #95 | — | Replaced message-count token estimates with measured OpenAI usage aggregated across ReAct iterations, omitted incomplete usage totals and removed fabricated cost estimates. Maintainer-approved with real-SDK loopback regressions for measured, zero and missing usage; 31 tests, lint and Node 20/22/24 CI passed. Merged upstream as 6478386 |
| promptfoo/mcp-agent-provider #96 | — | Fixed Streamable HTTP to legacy SSE fallback by retrying after connection negotiation fails with a 4xx StreamableHTTPError, rather than only falling back during transport construction. Closes the failed transport, creates a fresh MCP client and verifies compatibility against an end-to-end legacy SSE server fixture; Node 20/22/24 and Biome CI passed. Merged upstream as bf5f668 |
| promptfoo/promptfoo #11243 | — | Fixed Vertex Claude sampling resolution so explicit top_p: 0 and top_k: 0 values are preserved instead of being replaced or omitted. Maintainer verification covered 1,146 Google provider tests, typecheck, CLI build, formatting/lint and all 57 applicable PR checks |
| promptfoo/modelaudit #1859 | — | Preserved native SafeTensors routing for valid FDICT-shaped headers while retaining fail-closed compression routing for unknown, inconclusive and genuine compressed inputs. Superseded by maintainer PR #1863, merged as 2a5185a with my commits and co-authorship preserved |
| ethereum/go-ethereum | — | Corrected the eth RPC endpoint documentation |
| ethereum/ethereum-org-website #19272 | — | Synced the Glamsterdam proposal list, removing EIP-7610 and adding eth/72 (EIP-8070), EIP-8136 and snap/2 (EIP-8189). Shipped to production in ethereum.org v11.29.0 / #19406, where I was credited in the release contributors list. Maintainers also added me as an ethereum.org maintenance contributor in #19364 |
| ethereum/ethereum-org-website #19368 | — | Repaired contributor onboarding in the repository README: replaced two dead links, corrected build-locale setup to use .env.local, added the missing staging step before commit, and fixed first-push instructions with git push -u origin HEAD. Reproduced each failure path before the fix; approved by a maintainer and merged upstream as efb29af. Included in the ethereum.org v11.29.1 deployment (#19430), which explicitly credits me in its documentation changelog and contributor acknowledgements |
| google/skill-reach | — | Preserved query metadata across CSV and JSONL exchange formats |
| nasa/delta | — | Fixed cache eviction for files |
| Samsung/CredSweeper | Medium · scanner coverage | Fixed CRX3 payload extraction, so credentials inside current Chrome extensions are no longer skipped |
| ethsystems/works #51 | Medium · API reliability | Fixed a reproducible index-out-of-bounds panic in public rotortree snapshot level_len and get_node accessors when an otherwise valid tree reaches MAX_DEPTH (including before full leaf capacity). The root has no levels[MAX_DEPTH] slot, so root-level reads now use self.root. No production outage or remote exploit is claimed. Added red/green regressions for binary and ternary trees, sequential and batched insertions, invalid root indices, and empty/single-leaf controls. Locally validated with 107 default tests, 180 all-feature tests, 107 no-default-feature tests, Clippy and formatting; refined the tests after maintainer review. Approved by rymnc and merged upstream as 1449c62 |
| ethsystems/map | — | Clarified the ERC-3643 transfer and admin paths |
| ethsystems/map #203 | — | Replaced the unresolved Private DvP placeholder in the Trading domain with verified Private Repo, Private Stocks and Private Commodities use cases, and linked the Atomic DvP Settlement and Private Trade Settlement approaches. Validated with npm run validate:ci, npm run check-terms:ci and git diff --check; approved by rymnc and merged upstream as 8451037 |
| ethsystems/web #44 | — | Repaired four broken proof-of-concept and specification links across the private bonds, shielded transfers and cross-chain swap write-ups. Cherry-picked upstream in commit 82bd4f0, preserving my authorship |
| ethsystems/web #45 | — | Fixed glossary link handling so linked terms and definitions render correctly and root map documents resolve to their GitHub source. Cherry-picked upstream in commit 63f99bd, preserving my authorship; 58/58 tests passed and 218 pages built |
| ethsystems/web #46 | — | Fixed sibling RFP link routing so bare RFP Markdown links resolve to /rfps/... routes instead of unrelated graph routes. Incorporated upstream in commit 3330621, with my contribution and authorship explicitly credited |
| ethsystems/web #47 | — | Restored glossary definitions written on continuation lines without swallowing the next term or category, with regression coverage. Incorporated upstream in commit 3330621, with my contribution and authorship explicitly credited |
| ethsystems/web #48 | — | Replaced the retired Custom UTXO reference in Private Bonds Part 3 with the maintained Shielding pattern and added the corresponding map reference. Incorporated upstream in commit 3330621, with my contribution and authorship explicitly credited; combined suite passed 62/62 tests |
| ethsystems/web #50 | — | Corrected the FAQ’s Aztec privacy-model classification: Aztec is hybrid, with note-based private state and separate transparent public contract state, rather than purely account-based privacy. The FHE comparison is now limited to some confidential-token designs. Incorporated into main by the EthSystems maintainer as 638a7a1, with original commit authorship preserved and the upstream commit explicitly mirroring PR #50 |
| WhatsApp/erlang-language-platform #284 | — | Fixed Rebar3 Common Test runnables omitting the required --group flag for grouped tests, with a red/green regression covering grouped and ungrouped cases. The control run passed 1,809 tests apart from the new failing regression; workspace CI passed on tested Linux and macOS combinations. Imported into Meta's internal review and merged upstream by robertoaloi as 05020fd, confirmed by Meta's code-sync bot (GitHub PR closed without native merge) |
| Consensys/ask-o11y-plugin | — | Switched LLM requests from the deprecated max_tokens to max_completion_tokens, with tests. Shipped in v0.3.18 |
| NethermindEth/nethermind | — | Made engine_newPayloadV3+ reject null or missing withdrawals, blobGasUsed and excessBlobGas with -32602 instead of marking the payload INVALID. My fix and regression test, merged in a maintainer PR that extended the tests |
| NethermindEth/juno #4146 | Protocol correctness · JSON-RPC | Fixed JSON-RPC notifications emitting error responses for unknown methods and invalid parameters, violating the requirement that notifications receive no response. Regressions reproduce unexpected error objects in notification-only and mixed batches, while preserving replies for ID-bearing requests. Centralised the no-response gate after dispatch following maintainer review; approved by brbrr and merged upstream as 4c6b4d3 |
| NethermindEth/nethermind #13755 | Medium · protocol availability | Fixed the Amsterdam Engine API boundary: engine_getPayloadV5 now returns -38005 Unsupported fork at Amsterdam instead of dropping slotNumber and blockAccessList. Added a red/green regression and preserved Osaka V5 behaviour; merged upstream and closed #13713 |
| NethermindEth/nethermind #14228 | Medium · authentication integrity | Fixed JWT cache reuse accepting correctly signed tokens after their explicit exp. Cached authentication now enforces the same expiration boundary as fresh validation while preserving the fast path, with regressions across both validation paths; merged upstream as eeca264 |
| NethermindEth/dotnet-riscv #18 | — | Repaired the README's Stateless Executor reference after the old feature branch was deleted, pointing the RISC-V build pipeline to the current Nethermind.Stateless.Executor location on master. Validated that the old URL returned 404 and the replacement resolves; approved and merged upstream as 41038a0 |
| DefiLlama/defillama-sdk #266 | Cache correctness | Fixed getLogs cache coverage bookkeeping so nested and overlapping fetches preserve the maximum covered block (Math.max) and adjacent ranges merge without collapsing or truncating cached metadata. Added four red/green regression cases for nested, right-extending, adjacent and disjoint ranges; 4 Jest tests, TypeScript build and git diff --check passed. Maintainer g1nt0ki approved the fix; merged upstream as f286359. No missing-log incident claimed |
| DefiLlama/peggedassets-server | — | Corrected the EURR issuer attribution: Bridge Building S.A. issues it, Revolut distributes it |
| centrifuge/api-v3 | — | Added the Pharos block explorer URL |
| 0xPolygon/polygon-agent-cli #142 | Medium · transaction safety | Fixed x402-pay bypassing the CLI's dry-run mode and unconditionally broadcasting funding transactions. Integrated shared --broadcast / --dry-run flags and persisted transaction mode, added structured payment previews, and covered both standard x402 and Bazaar flows with regressions proving no funds are sent during dry runs. Fixes #130; merged upstream as b3e81d0 |
| solana-foundation/solana-web3.js #3943 | Medium · release integrity | Added runtime smoke tests for both IIFE browser bundles. Review surfaced a Rollup substitution bug that made the v3 bundles throw in browsers; the PR merged with the maintainer's fix |
| solana-foundation/solana-com #2150 | Medium · data freshness | Fixed slot-time block requests rejecting newer blocks containing Solana v1 transactions, which could leave the endpoint serving cached blocks minutes old despite a four-second refresh target (#2141). Raised maxSupportedTransactionVersion to 1, with regression tests for the exact JSON-RPC request and program ID resolution using static and loaded address-table keys. Approved and merged upstream as a233795 |
Impact labels describe demonstrated security, scanner-integrity, API-reliability, protocol-correctness, protocol-availability, data-availability or release-integrity consequences; severity ratings are evidence-based, self-assessed and not upstream-assigned.
Also:
- proposed the fix for a reported Claude Code startup failure in Trail of Bits'
second-opinionplugin (#303). The maintainer shipped the same fix in #306.
- Open-source contributions across Ethereum, security and developer tooling
- Finding and fixing high-impact technical issues
- Building visible proof of work through code, audits and documentation
Validated upstream changes that have not merged. Review and test status are stated explicitly; closed or superseded PRs are recorded separately.
| Project | Change | Status |
|---|---|---|
| ethereum/ethereum-org-website #19409 | Prevents a failed Google Sheets category request from replacing a previously cached apps category with an empty result. A mocked 503 regression proves the fetch rejects instead of returning partial data; the PR reports 1,324 passing tests on the fork |
Open · awaiting maintainer review (not merged) |
| NethermindEth/nethermind #14338 | Corrected Docker image metadata to advertise P2P discovery on 30303/udp alongside 30303/tcp, with regression coverage of standard and chiseled images. Published image metadata reproduced the omission; patched builds and validation CI passed. This affects automatic port publishing, not the runtime networking configuration |
Approved by three reviewers · awaiting merge (AnkushinDaniil, manusw7, LukaszRozmej) |
| NethermindEth/nethermind #14372 | Normalises malformed receipt post-state lengths to RlpException across standard, eth/69 and Optimism decoders, with 5/31/33/34-byte regressions. The Optimism follow-up and missing System.Diagnostics import were addressed; the latest review found no blocking issues |
Approved after follow-up · awaiting merge (LukaszRozmej) |
This section records useful findings that did not result in a merge of my own PR. Superseded fixes are not counted as merged code contributions.
| Project | Outcome | Evidence and contribution |
|---|---|---|
| NethermindEth/pluto #714 | Superseded · not merged | Reproduced missing topic labels in warning/error metrics at info and submitted a focused integration regression. Maintainer closed my PR as superseded by #720, which implemented related tracing fixes. My PR was not merged |
| NethermindEth/pluto #715 | Superseded · not merged | Reproduced OTLP header credentials appearing in warning logs and proposed redaction. Maintainer closed my PR because the issue was already addressed in #717. My PR was not merged |
| apple/embedding-atlas #260 | Confirmed · fixed independently | Identified the drag-release callback passing raw MouseEvent instead of the declared CursorValue; provided a regression checking coordinates and modifier keys. Utility and viewer tests passed (103 and 143). The identical one-line e2 → v2 correction shipped separately in Apple commit 73e4901 / #261. Maintainer confirmed the prior fix and closed my PR without merging it |
| solana-foundation/surfpool #814 | Technical review · issue closed | Reviewed the concurrent slot-lifecycle PR #778, highlighted the missing embedded offline SDK transaction-mode / signature-status polling regression, and proposed a comparative reproduction strategy. Issue originally reported by ifiokjr; closed as completed without a fixing commit identified in its issue timeline. No upstream patch or original discovery is claimed |
| Area | Result |
|---|---|
| Security research | H1 2026 Digital Asset Security Review: 100+ incidents, $850M in losses |
| Exploit forensics | $287M+ in losses reconstructed |
| Organic reach | 2M+ impressions in 90 days, zero paid spend |
| Community | 2,300+ member security community |
| Disclosures | Acknowledged by the DoD (DARPA, Air Force, Navy), Toyota and Philips |
| Category | Created W3SPM (Web3 Security Posture Management) |