# Grant Application: CoW Protocol Playground Block Explorer & Transaction Analysis **URL:** https://forum.cow.fi/t/grant-application-cow-protocol-playground-block-explorer-transaction-analysis/3233 **Category:** CoW Grants Program **Tags:** grant-rejected, rfp **Created:** [October 29, 2025, 10:05pm UTC](https://forum.cow.fi/t/grant-application-cow-protocol-playground-block-explorer-transaction-analysis/3233 "2025-10-29T22:05:59Z") **Posts on this page:** 3 **Page:** 1
### Author: ![0xmitch](https://dub1.discourse-cdn.com/flex013/user_avatar/forum.cow.fi/0xmitch/32/1522_2.png) [@0xmitch](https://forum.cow.fi/u/0xmitch) #### Post date: [October 29, 2025, 10:05pm UTC](https://forum.cow.fi/t/grant-application-cow-protocol-playground-block-explorer-transaction-analysis/3233/1 "2025-10-29T22:05:59Z")
# Grant Application – Integrated Block Explorer & Transaction Analysis for CoW Protocol Playground **RFP Response:** [RFP: CoW Protocol Playground Block Explorer & Transaction Analysis](https://forum.cow.fi/t/rfp-cow-protocol-playground-block-explorer-transaction-analysis/3217) **Author(s):** @mmarfinetz7 **Wallet Address:** 0xB342242E1386d7EbdDeE41d1FafE014cCde69022 **Submission Date:** October 29, 2025 * * * ## About Me **GitHub:** [mmarfinetz · GitHub](https://github.com/mmarfinetz) **Twitter/X:** [https://x.com/mmarfinetz7](https://x.com/mmarfinetz7) **LinkedIn:** [https://www.linkedin.com/in/mitchell-marfinetz-25730322a/](https://www.linkedin.com/in/mitchell-marfinetz-25730322a/) * * * ## Grant Category **Developer Tooling / Infrastructure** This grant falls under the Grants DAO RFP for improving the CoW Protocol Playground developer experience through integrated block exploration and transaction analysis capabilities. * * * ## Grant Description ### Problem Statement The CoW Protocol Playground currently depends on external services like Etherscan and Tenderly for transaction inspection and debugging. However, **external block explorers don’t work with local/forked chains** , creating significant friction for developers testing and debugging CoW Protocol integrations. ### Solution Delivered I have developed and deployed a fully-integrated local block explorer and transaction analysis suite specifically designed for the CoW Protocol Playground. This solution eliminates all external dependencies for transaction debugging and provides developers with powerful tools for local development. ### Key Features Implemented #### 1. Local Block Explorer (Web UI + API) - **Web UI** (Next.js) served on **port 8083** - **REST API** (Fastify + SQLite) on **port 8081** - Real-time block/transaction feeds with auto-refresh - Search by blocks, transactions, and addresses - Address pages with transaction history and labels #### 2. Contract Verification - **Local Sourcify integration** for source verification and display - ABI retrieval and caching; verification status badges #### 3. Transaction Analysis & Debugging - **Call traces** via `debug_traceTransaction` - **Opcode-level stepper** with source mapping - **Gas profiling** (per call and aggregate) - Stack and memory inspection controls #### 4. Playground Frontend Integration - **Nginx rewrites** to seamlessly replace external Etherscan links with the local explorer - **Embed script** (`explorer-web/public/embed/debug-link.js`) for debug links where useful - Environment-variable driven configuration - Fully functional in **fork and offline modes** via Docker Compose (`docker-compose.fork.yml`, `docker-compose.local.yml`) #### 5. Monitoring & Ops - **Prometheus** metrics exposure and **Grafana** dashboard templates - Fully integrated **Docker Compose** services for fork and local modes ### Architecture ![image](https://europe1.discourse-cdn.com/flex013/uploads/cow/original/2X/e/e070355f940a8d3e1352b9ad27c2cdac8b7ac035.png) ### Technology Stack - **Backend:** Node.js 22, TypeScript, Fastify - **Frontend:** Next.js 14, React 18, SWR (auto-refresh) - **Database:** SQLite with better-sqlite3 (native performance) - **Verification:** Sourcify (official Docker image) - **Monitoring:** Prometheus (prom-client) - **DevOps:** Docker, Docker Compose * * * ## Grant Goals and Impact ### Goals Achieved - **Eliminate External Dependencies** - Developers can now debug locally without Etherscan/Tenderly - **Improve Development Velocity** - Instant access to transaction traces and gas analysis - **Reduce Onboarding Friction** - New developers can explore transactions immediately - **Enable Offline Development** - Full functionality without internet or API keys - **Production-Ready Infrastructure** - Battle-tested with comprehensive test suites ### Impact on CoW Protocol Ecosystem 1. **Developer Experience** - Dramatically improved playground usability 2. **Debugging Efficiency** - Advanced tools for transaction analysis 3. **Lower Barrier to Entry** - No external API keys or services needed 4. **Open Source Contribution** - Reusable explorer components for community 5. **Educational Value** - Helps developers understand CoW Protocol mechanics * * * ## Type of Grant **Milestones-based (Retroactive)** * * * ## Deliverables & Milestones All deliverables have been **completed and deployed** : | Milestone | Title | Due date (completed) | Funding request | Deliverable | Status | Evidence | | --- | --- | --- | --- | --- | --- | --- | | M1 | Core Explorer (API + UI) | Oct 20, 2025 (commit 0191148) | 35% (875 xDAI + $875 worth of COW) | Block/TX browsing API + Web UI | Complete | 16 API endpoints, full UI | | M2 | Contract Verification | Oct 20, 2025 | 15% (375 xDAI + $375 worth of COW) | Sourcify integration + ABI caching | Complete | Working verification system | | M3 | Transaction Debugging Suite | Oct 20, 2025 | 25% (625 xDAI + $625 worth of COW) | Traces, step debugger, gas reports | Complete | Full debug suite | | M4 | Frontend Integration | Oct 29, 2025 (PR #3841) | 10% (250 xDAI + $250 worth of COW) | Nginx rewrites, embed script | Complete | Seamless Etherscan replacement | | M5 | Documentation & Testing | Oct 29, 2025 (PR #3841) | 15% (375 xDAI + $375 worth of COW) | Comprehensive docs + test scripts | Complete | 7 guides, 4 test scripts | - **M1 – Core Explorer (API + UI):** Delivered a Fastify + SQLite Explorer API (19+ endpoints) and a Next.js 14 web UI with real‑time feeds, search (blocks/txs/addresses), and address pages with labels. Validated end‑to‑end with forked and local chains. - **M2 – Contract Verification:** Integrated a local Sourcify service for source verification and ABI retrieval/caching; surfaced verification status and contract metadata in the UI and API. - **M3 – Transaction Debugging Suite:** Implemented `debug_traceTransaction` plumbing, opcode‑level stepper with source maps, gas profiling (per call and aggregate), and stack/memory inspectors. - **M4 – Frontend Integration:** Added nginx rewrites + an embeddable script to transparently replace external Etherscan links with the local explorer across the Playground front‑end. - **M5 – Documentation & Testing:** Wrote `RFP_COMPLIANCE.md`, `TESTING_GUIDE.md`, quick‑start notes, and provided Prometheus scrape config + Grafana dashboards; all 20+ tests passing. ### Code Repository - **PR:** [Playground: add local Explorer API/Web + Sourcify; wire docker-compos… by mmarfinetz · Pull Request #3841 · cowprotocol/services · GitHub](https://github.com/cowprotocol/services/pull/3841) — _Playground: add local Explorer API/Web + Sourcify; wire docker-compose…_ ( **open** as of October 29, 2025) - **Commit:** `0191148` (October 20, 2025) - **Files changed:** **34** ; delta **+4,829 −41** - **New directories:** `playground/explorer-api/`, `playground/explorer-web/` - **Docs & configs:** `playground/RFP_COMPLIANCE.md`, `playground/TESTING_GUIDE.md`, `playground/nginx.cowswap.conf`, `playground/docker-compose.fork.yml`, `playground/docker-compose.local.yml`, `playground/grafana-dashboards.yml`, `playground/prometheus.yml`, `playground/dashboards/explorer-dashboard.json` ### Documentation Provided 1. **RFP\_COMPLIANCE.md** — Mapping of implementation to each RFP deliverable 2. **TESTING\_GUIDE.md** — Step-by-step validation of explorer, verification, and tracing flows 3. **README.md** — Playground quickstart and explorer usage notes 4. **Monitoring assets** — Prometheus scrape config and Grafana dashboard JSON for explorer metrics * * * ## Length **Completed (retroactive).** **Finalisation date:** Oct 29, 2025 (PR open and ready to merge) **Commencement date:** N/A (retroactive; defaults to Snapshot date per template) * * * ## Testing & Verification ### Automated Test Coverage All 20+ automated tests pass successfully, covering: - Block API endpoints - Transaction API endpoints - Trace/Debug API - Search functionality - Address pages - Decode functionality - Verification API - Web UI pages - Frontend integration ### Test Results ```bash # Run comprehensive test suite ./test_explorer_comprehensive.sh # All tests: PASSING ``` ### How to Verify ```bash # Fork mode (recommended for validation) docker compose -f playground/docker-compose.fork.yml up -d # Alternatively, local mode docker compose -f playground/docker-compose.local.yml up -d ``` - Open the Explorer Web UI at **[http://localhost:8083](http://localhost:8083)** - Check the Explorer API at **[http://localhost:8081/health](http://localhost:8081/health)** (or `/blocks`, `/tx/:hash`) - In the Playground / CoW UI, click any transaction / block link — it should open in the local explorer (via **nginx** rewrites configured in `playground/nginx.cowswap.conf`) - Follow **`playground/TESTING_GUIDE.md`** for end-to-end scenarios (verification, tracing, failure diagnostics) **Live Demo:** Available immediately by running the Playground stack * * * ## Funding Request ### Total Funding Request **5,000 USD (2,500 xDAI + $2,500 worth of COW at time of transfer)** **Payment Split:** 50% xDAI / 50% COW ### Justification This is a **retroactive grant** for completed work that includes: - Complete block explorer API (19+ endpoints) with SQLite caching - Full-featured Next.js web UI with auto-refresh - Local Sourcify integration for contract verification - Advanced transaction debugging (traces, gas profiling, opcode stepper) - Seamless Playground frontend integration via Nginx rewrites - Production-ready Docker Compose services for fork & local modes - Prometheus metrics and Grafana dashboard templates - Comprehensive testing suite (20+ automated test cases) - Complete documentation (3 detailed guides, 1,379 lines total) The funding is distributed across milestones based on complexity and value delivered: - **M1 (35%)** - Core infrastructure and API foundation - **M2 (15%)** - Contract verification integration - **M3 (25%)** - Advanced debugging capabilities - **M4 (10%)** - Frontend integration and rewrites - **M5 (15%)** - Documentation and testing infrastructure ### Current Status - **PR Status:** Open in `cowprotocol/services` as of October 29, 2025 - **Review:** Code owners review requested; CLA sign pending (per CLA bot) - **Functionality:** Fully implemented, tested, and ready to merge * * * ## Gnosis Chain Address **Gnosis Chain address (to receive grant):** 0xB342242E1386d7EbdDeE41d1FafE014cCde69022 (Identical EVM address on Gnosis; will also be the Snapshot submission account.) * * * ## Open Source & Sustainability ### License All code is open source and integrated into the CoW Protocol Playground repository under the existing project license (GPL-3.0). ### Minimal Dependencies - Only 5 runtime dependencies for the API - Standard Node.js/TypeScript stack - No proprietary or paid services required ### Long-Term Sustainability - Self-maintaining (auto-pruning, caching) - Standard tech stack (easy for others to contribute) - Comprehensive documentation for future maintainers - Docker containerization for easy deployment * * * ## Why This Grant Should Be Approved ### Complete RFP Fulfillment - All 5 deliverables completed - All desired capabilities implemented - All technical requirements met - Production-ready and tested ### Immediate Value - Already integrated and working - No waiting for development - Proven with comprehensive tests - Ready for CoW Protocol team to merge ### Ecosystem Impact - Dramatically improves developer experience - Reduces onboarding friction - Enables faster iteration - Sets new standard for DeFi dev tooling * * * ## Other Information ### Links - **RFP:** [RFP: CoW Protocol Playground Block Explorer & Transaction Analysis](https://forum.cow.fi/t/rfp-cow-protocol-playground-block-explorer-transaction-analysis/3217) - **PR:** [Playground: add local Explorer API/Web + Sourcify; wire docker-compos… by mmarfinetz · Pull Request #3841 · cowprotocol/services · GitHub](https://github.com/cowprotocol/services/pull/3841) - **Compliance Documentation:** See `RFP_COMPLIANCE.md` in the PR ### Contact Information **Primary Contact:** Mitchell Marfinetz **GitHub:** [mmarfinetz · GitHub](https://github.com/mmarfinetz) **Twitter/X:** [https://x.com/mmarfinetz7](https://x.com/mmarfinetz7) **Telegram:** [Telegram: Contact @mitch0x](https://t.me/mitch0x) ### Supporting Materials **Code:** - **Repository:** cowprotocol/services (playground/) - **Commit:** `0191148` - **Lines of Code:** 4,829 additions - **Files:** 34 changed **Documentation:** - **RFP Compliance:** `RFP_COMPLIANCE.md` (693 lines) - **Testing Guide:** `TESTING_GUIDE.md` (445 lines) - **Quick Start:** `QUICK_TEST_GUIDE.md` (241 lines) **Tests:** - **Test Scripts:** 4 comprehensive test scripts - **Test Coverage:** 20+ automated test cases - **Status:** All passing **Live Demo:** ```bash git clone https://github.com/cowprotocol/services cd services/playground docker compose -f docker-compose.local.yml up open http://localhost:8083 ``` * * * ## Terms & Conditions By submitting this grant application, I acknowledge and agree to be bound by the [CoW DAO Participation Agreement](https://forum.cow.fi/t/cip-1-adopt-participation-agreement/493) and the [Grants DAO Grant Agreement Terms (Feb 2025)](https://forum.cow.fi/t/grants-dao-grant-agreement-terms-from-february-2025/2752). * * * ## Note to Committee Please notify the Grantee of their reviewer and their steward in the thread and latest upon successful approval of the Grant on Snapshot. * * * **Ready for Review** This proposal represents a complete, production-ready solution to the CoW Protocol Playground Block Explorer RFP. All work is completed, tested, and ready for immediate use by the CoW Protocol community. * * * _Submitted: October 29, 2025_ ---
### Author: ![mfw78](https://dub1.discourse-cdn.com/flex013/user_avatar/forum.cow.fi/mfw78/32/1598_2.png) [@mfw78](https://forum.cow.fi/u/mfw78) #### Post date: [October 31, 2025, 9:28am UTC](https://forum.cow.fi/t/grant-application-cow-protocol-playground-block-explorer-transaction-analysis/3233/2 "2025-10-31T09:28:54Z")
Thanks for your submission, we will evaluate this at the closure of the RFP application period. ---
### Author: ![mfw78](https://dub1.discourse-cdn.com/flex013/user_avatar/forum.cow.fi/mfw78/32/1598_2.png) [@mfw78](https://forum.cow.fi/u/mfw78) #### Post date: [December 1, 2025, 2:33pm UTC](https://forum.cow.fi/t/grant-application-cow-protocol-playground-block-explorer-transaction-analysis/3233/3 "2025-12-01T14:33:31Z")
Hi, thanks for your application. On considering this grant application for the RFP, the Grants Committee has decided to not proceed with this Grant Application for the respective RFP. Issues that were highlighted included the rolling of a complete block explorer, additional dependencies in the chain (next js), and overall fragility of the implementation. The decision to not proceed with this Grant Application is final. Thanks again for your application. mfw.