Switch to free public Sepolia RPCs (PublicNode + dRPC), slow indexer polling; bump submodules

Co-authored-by: Cursor <cursoragent@cursor.com>

Author: TranspaChain Builder

.env.example

@@ -1,16 +1,23 @@
 # Copy to .env on EC2 (~/transpachain/.env) and fill in values
 # See each submodule's .env.example for details
 
+# Primary Sepolia RPC — free public endpoint (no API key). ALCHEMY_SEPOLIA_URL still
+# works as an alias and takes precedence when set; leave it empty to stay on free RPCs.
+SEPOLIA_RPC_URL=https://ethereum-sepolia-rpc.publicnode.com
+# Fallback when primary is rate-limited or down
+SEPOLIA_RPC_FALLBACK_URL=https://sepolia.drpc.org
 ALCHEMY_SEPOLIA_URL=
+# Indexer live-poll interval (ms) — 60000 conserves public-RPC quota
+INDEXER_POLL_INTERVAL_MS=60000
 DEPLOYER_PRIVATE_KEY=
 ETHERSCAN_API_KEY=
 PINATA_API_KEY=
 PINATA_SECRET_KEY=
 MONGODB_URI=mongodb://localhost:27017/transpachain
 CORS_ORIGIN=https://transpachain.site
-# Block when contracts were deployed (Etherscan). Omit or 0 to skip backfill.
-# Alchemy free tier: keep range small OR set INDEXER_LOG_CHUNK_SIZE=10 (default).
-DEPLOY_FROM_BLOCK=11146320
+# Block when contracts were deployed (Etherscan). 0 = skip backfill (set 0 once backfill is done).
+# On free/public RPC tiers: keep range small OR set INDEXER_LOG_CHUNK_SIZE=10 (default).
+DEPLOY_FROM_BLOCK=0
 INDEXER_LOG_CHUNK_SIZE=10
 
 # Backend indexer + API
@@ -23,6 +30,7 @@ IMPACT_NFT_ADDRESS=0xF2556FcccaE36A6d8Da0C75a863CA7368FC6761a
 # GHCR deploy (EC2): FRONTEND_TAG=<sha> ./scripts/deploy-frontend-ec2.sh
 # FRONTEND_IMAGE=ghcr.io/levianth146/transpachain-frontend:${FRONTEND_TAG:-latest}
 FRONTEND_TAG=latest
+# Optional — leave empty to use free PublicNode/dRPC transports in the browser
 NEXT_PUBLIC_ALCHEMY_KEY=
 NEXT_PUBLIC_CHARITY_CORE_ADDRESS=0xCE017838BfE2785CB2458bb205770663bEB9b0B8
 NEXT_PUBLIC_DONATION_VAULT_ADDRESS=0xEb421D07E885EeB2B8E9ea408FF284013F872Db1

backend

@@ -40,6 +40,7 @@ services:
       CORS_ORIGIN: ${CORS_ORIGIN:-https://transpachain.site}
       DEPLOY_FROM_BLOCK: ${DEPLOY_FROM_BLOCK:-}
       INDEXER_LOG_CHUNK_SIZE: ${INDEXER_LOG_CHUNK_SIZE:-10}
+      INDEXER_POLL_INTERVAL_MS: ${INDEXER_POLL_INTERVAL_MS:-60000}
     healthcheck:
       test: ["CMD-SHELL", "node -e \"fetch('http://127.0.0.1:3001/health').then(r=>process.exit(r.ok?0:1)).catch(()=>process.exit(1))\""]
       interval: 10s

docker-compose.prod.yml

@@ -32,6 +32,7 @@ services:
       CORS_ORIGIN: ${CORS_ORIGIN:-https://transpachain.site}
       DEPLOY_FROM_BLOCK: ${DEPLOY_FROM_BLOCK:-}
       INDEXER_LOG_CHUNK_SIZE: ${INDEXER_LOG_CHUNK_SIZE:-10}
+      INDEXER_POLL_INTERVAL_MS: ${INDEXER_POLL_INTERVAL_MS:-60000}
     healthcheck:
       test: ["CMD-SHELL", "node -e \"fetch('http://127.0.0.1:3001/health').then(r=>process.exit(r.ok?0:1)).catch(()=>process.exit(1))\""]
       interval: 10s

docker-compose.yml

@@ -48,12 +48,18 @@ Copy `.env.example` → `.env` on EC2. Critical values:
 ```env
 # Production
 CORS_ORIGIN=https://transpachain.site
-ALCHEMY_SEPOLIA_URL=https://eth-sepolia.g.alchemy.com/v2/YOUR_KEY
+# Free public RPCs — no API key required. ALCHEMY_SEPOLIA_URL is an optional
+# paid-RPC alias that takes precedence when set; leave it empty otherwise.
+SEPOLIA_RPC_URL=https://ethereum-sepolia-rpc.publicnode.com
+SEPOLIA_RPC_FALLBACK_URL=https://sepolia.drpc.org
+ALCHEMY_SEPOLIA_URL=
 MONGODB_URI=mongodb://mongodb:27017/transpachain
 
-# Indexer — Sepolia contract deploy block (Etherscan). 0 = skip backfill.
-DEPLOY_FROM_BLOCK=11146320
+# Indexer — Sepolia contract deploy block (Etherscan). 0 = skip backfill (already done).
+DEPLOY_FROM_BLOCK=0
 INDEXER_LOG_CHUNK_SIZE=10
+# Live-poll interval (ms) — 60000 conserves public-RPC quota
+INDEXER_POLL_INTERVAL_MS=60000
 
 # Backend contract addresses
 CHARITY_CORE_ADDRESS=0xCE017838BfE2785CB2458bb205770663bEB9b0B8
@@ -62,7 +68,8 @@ GOVERNANCE_DAO_ADDRESS=0xd655d85ddACc386901487CE8E1ec45BD4F872A19
 IMPACT_NFT_ADDRESS=0xF2556FcccaE36A6d8Da0C75a863CA7368FC6761a
 
 # Frontend build-args (baked into client JS at docker build)
-NEXT_PUBLIC_ALCHEMY_KEY=your_key
+# Optional — leave empty to use free PublicNode/dRPC transports in the browser
+NEXT_PUBLIC_ALCHEMY_KEY=
 NEXT_PUBLIC_CHARITY_CORE_ADDRESS=0xCE017838BfE2785CB2458bb205770663bEB9b0B8
 NEXT_PUBLIC_DONATION_VAULT_ADDRESS=0xEb421D07E885EeB2B8E9ea408FF284013F872Db1
 NEXT_PUBLIC_GOVERNANCE_DAO_ADDRESS=0xd655d85ddACc386901487CE8E1ec45BD4F872A19