Stellar Community Fund

By OBSRVR Prism

Prism: Soroban-First Block Explorer

SCF #41

$80.0K

Build

Awarded

Products & Services

OBSRVR Prism extends our existing open-source in development block explorer — the Obsrvr Intelligence Console (Terminal) — with full Soroban-first capabilities. Terminal already provides a contract-centric explorer with tiered hot/cold storage and real-time WebSocket streaming. Prism adds the missing Soroban display layer: human-readable transactions, CAP-67 event support, and complete ledger history from genesis.

Existing Foundation — What's Already Built (Stellar Integration):

Terminal is a block explorer running on Obsrvr Lake with tiered storage — PostgreSQL for recent data and S3 Parquet/DuckDB for full history.

Full History (Stellar Integration): Ingests all 61M+ Stellar ledgers using flowctl (open-source) and our gRPC-based TTP processor pipeline, streaming from Stellar archives into PostgreSQL. No gaps in Soroban-era data.

Human-Readable Soroban (Impact): Implements SEP-41 and SEP-50 to transform opaque XDR into plain language — "Swapped 100 USDC for 1,250 XLM via Soroswap." Makes DeFi, collectibles, and smart contract activity accessible to all users.

CAP-67 Event Stream (Stellar Integration): Full unified event stream with swap detection heuristics for major DEXes (Soroswap, Aquarius, Phoenix). Filterable by contract, function call, event type, and token.

Classic + Soroban Parity (Impact): Unified interface for classic operations, SAC tokens, SEP-39, and Soroban smart contracts — complete coverage of the Stellar ecosystem in one explorer.

Obsrvr Lake Backend (Stellar Integration): Bronze layer (immutable raw XDR in object storage) + Silver layer (transformed and filterd) backed by Stellar Galexie archives. Already running on testnet. Long-term sustainability guaranteed — explorer infrastructure is maintained as part of Obsrvr's core platform, not an isolated grant project.

Fully Open Source: Pipeline, processors, API, and frontend. Some core components already public on GitHub.

Requested Budget

$80.0K

Traction Evidence

Open-Source Tooling (Live on GitHub):

nebu v0.3.8 — Stellar ledger processor with 10 built-in processors (contract-events, token-transfer, usdc-filter, contract-invocation, etc.). https://github.com/withObsrvr/nebu
Flowctl based TTP Processor Pipeline — gRPC microservices for streaming Stellar events to PostgreSQL. Built on SDF's TTP-as-a-Service architecture concept for processors (stellar/go#5637). https://github.com/withObsrvr/ttp-processor-demo
Terminal (Obsrvr Intelligence Console) — Contract-centric block explorer and developer terminal for Stellar/Soroban. Features tiered storage (Hot PostgreSQL + Cold S3 Parquet/DuckDB), natural language console commands, Agent/LLM-friendly APIs, real-time WebSocket streaming, and Bloomberg Terminal-inspired multi-column interface. Built with Go and HTMX. Prism extends Terminal with full CAP-67/SEP-41/SEP-50 support. https://github.com/withObsrvr/terminal

Running Infrastructure:

Obsrvr Lake operational on testnet (DigitalOcean) — PostgreSQL hot layer + object storage, processing testnet ledgers in real-time with Bronze/Silver data model.

Mainnet Data Processing (Demonstrated):

Successfully processed live mainnet Soroban contract events using nebu/flowctl cecoding multi-hop DEX swaps, USDC transfers, SAC operations, and token minting in real-time.

Ecosystem Alignment:

Purpose-built for Stellar from day one. Deep familiarity with XDR encoding, Soroban contract architecture, and standards landscape (SEP-41, SEP-50, CAP-67, SEP-39).

Previous chats that lead to initial explorer work (Terminal) even though the topics were not specific to explorers:

November 10th 2024**[12:50 PM]Jake | SDF** Hey there! I’d love to hear about your building for observr. Freighters just looking for a provider for pricing data so we can do something like this
May 25th 2025 [2:25 PM]Jake | SDF:
- As a third party service, my gut is that most clients would prefer the service to host the data and expose an API for them to query, maybe with the option to subscribe to webhooks. I've seen some indexers that offer functionality to write directly to the client's database or other form of storage but IMO its not difficult to parse a webhook or API response and write it to your preferred storage yourself.
May 25th 2025 [2:25 PM]Jake | SDF:
- My team (wallets) is building our own indexer we'll use for Freighter. It'll use TTP for balance changes but we're aiming to index more than that (signers, allowances, defi positions, etc.)
May 25th 2025 [2:29 PM]Jake | SDF:
- That being said most wallets, especially the larger multichain ones, aren't looking for the deep support for Stellar our indexer will provide, and are largely just interested in balance changes for fungible and nonfungible tokens
June 25th 2025 [9:53 AM]jcanneto:
- Wondering what your thoughts on building out use case specific apis are? We've been seing a lot of need for token transfer or balance related apis that are more or less plug and play. Is this something you would be interested in providing?

Tranche 1 (Deliverable Roadmap) - MVP

[Deliverable 1] Mainnet Ingestion Pipeline

Brief description: Deploy nebu and TTP processor pipeline on mainnet infrastructure, ingesting live Stellar ledgers in real-time via gRPC streaming to PostgreSQL.
How to measure completion: Pipeline running with <30 second latency from network tip. Publicly accessible health endpoint showing ingestion status and current ledger sequence.
Budget: $5,000

[Deliverable 2] Historical Backfill ≥50%

Brief description: Begin full-history backfill from Stellar genesis (ledger 1) through present. Ingest raw ledger data into Bronze layer (object storage) and normalized data into Silver layer (PostgreSQL).
How to measure completion: ≥30M of ~61M ledgers ingested and indexed. Backfill progress dashboard publicly visible. API queries against early ledger data return correct results.
Budget: $5,000

[Deliverable 3] Explorer Frontend on Testnet

Brief description: Adapt existing Terminal explorer for Soroban-first display. Deploy on testnet with ledger list, transaction detail, account history, global search, and classic asset rendering including SAC and SEP-39 tokens.
How to measure completion: Publicly accessible testnet explorer URL. Classic operations (payments, path payments, offers, trustlines) displayed correctly. SAC token balances and transfers visible. Verified against known testnet transactions.
Budget: $3,000

[Deliverable 4] Core API Endpoints

Brief description: REST API endpoints for ledgers, transactions, accounts, operations, and events. Built on existing Terminal API layer.
How to measure completion: Endpoints live on testnet: /ledgers, /transactions/{hash}, /accounts/{id}, /operations, /events. Response times <400ms. API documentation published.
Budget: $3,000

Tranche 2 (Deliverable Roadmap) - Testnet

[Deliverable 1] CAP-67 Unified Event Stream

Brief description: Implement full CAP-67 contract event ingestion and display. Dedicated event stream view showing decoded topics and data, combining classic effects and Soroban events in a single filterable interface.
How to measure completion: Event stream page live on testnet. Events filterable by contract address, event type, and function call. Verified against known mainnet Soroban contract events.
Budget: $4,000

[Deliverable 2] SEP-41 + SEP-50 Human-Readable Display

Brief description: Implement SEP-41 token interface rendering and SEP-50 human-readable transaction summaries. Token transfers display human-readable names and decimal-adjusted amounts. Transactions show plain-language descriptions.
How to measure completion: Transaction detail pages show summaries like "Sent 500 USDC from G...ABC to G...XYZ" and "Swapped 100 USDC for 1,250 XLM via Soroswap." Verified against known USDC, yXLM, and AQUA transfers on mainnet.
Budget: $4,000

[Deliverable 3] Swap Detection & Function Call Filtering

Brief description: Heuristic-based swap detection for major Soroban DEXes (Soroswap, Aquarius, Phoenix). UI and API filtering by smart contract function name (e.g., swap, transfer, mint).
How to measure completion: Swaps displayed as "Swapped X TokenA for Y TokenB via [DEX]." API supports fn_call query parameter. UI filter functional. Verified against known DEX transactions.
Budget: $4,000

[Deliverable 4] Historical Backfill ≥90%

Brief description: Continue full-history ingestion. Target ≥55M of ~61M ledgers processed and indexed across Bronze and Silver layers.
How to measure completion: Backfill dashboard showing ≥90% progress. Early Soroban-era transactions (2024) queryable and returning correct results.
Budget: $5,000

[Deliverable 5] Mainnet Infrastructure Scaling

Brief description: Optimize database indexes and caching for production query patterns. Scale storage tiers for growing dataset. Prepare infrastructure for mainnet launch load.
How to measure completion: Query performance benchmarks showing <400ms on representative queries against full dataset. Storage capacity confirmed for 12+ months of growth.
Budget: $7,000

Tranche 3 (Deliverable Roadmap) - Mainnet

[Deliverable 1] Full History Complete & Verified

Brief description: Complete ingestion of all ~61M+ Stellar ledgers from genesis to present. Verify data integrity across multiple network eras.
How to measure completion: 100% of ledgers ingested. Spot-check verification against known historical transactions (pre-Soroban, protocol v20 launch, recent). Zero gaps in ledger sequence.
Budget: $6,000

[Deliverable 2] Production Mainnet Deployment

Brief description: Launch explorer at public URL serving live mainnet data. CDN-backed frontend, uptime monitoring, and alerting configured.
How to measure completion: Explorer live and publicly accessible. Uptime monitoring dashboard active. Real-time data within 30 seconds of network tip.
Budget: $8,000

[Deliverable 3] Load Testing

Brief description: Comprehensive load testing demonstrating production readiness under parallel user load.
How to measure completion: Published load test report showing stable <400ms API response times under ≥100 concurrent requests. Methodology and raw results included.
Budget: $5,000

[Deliverable 4] Documentation & Example Integrations

Brief description: Complete documentation suite and example integrations. API reference, architecture guide, deployment guide, contributor guide. Embeddable transaction widget and API usage examples in Python and JavaScript.
How to measure completion: Docs published on project site and GitHub. Both example integrations functional with README instructions.
Budget: $3,000

[Deliverable 5] Open Source Release

Brief description: Publish complete explorer codebase under permissive open-source license. Include contributing guidelines, issue templates, and CI/CD pipeline.
How to measure completion: Public GitHub repository with full source, LICENSE file, CONTRIBUTING.md, CI passing, and tagged release.
Budget: $2,000

[Deliverable 6] Post-Launch Infrastructure

Brief description: Provision infrastructure to ensure explorer availability and data freshness beyond the grant period.
How to measure completion: Infrastructure contracts/prepayment receipts for 6 months post-launch. Explorer operational commitment through December 2026.
Budget: $8,000