x402 Base Pulse

Real-time payment protocol analytics for Coinbase x402 on Base

Track every x402 payment settlement on Base. This Substreams detects when facilitators call transferWithAuthorization on USDC to settle HTTP 402 payments, extracting payer, recipient, amount, and facilitator data from each settlement.

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How It Works

The x402 protocol enables internet-native payments using the HTTP 402 status code. When a client wants to access a paid resource:

1. Server responds with HTTP 402 + payment requirements
2. Client signs an EIP-3009 authorization
3. Facilitator calls transferWithAuthorization on USDC to settle payment on-chain
4. USDC emits AuthorizationUsed + Transfer events
5. This Substreams captures those events and extracts settlement data

Modules

Module	Kind	Description
map_x402_settlements	Map	Pairs AuthorizationUsed + Transfer events on USDC to extract settlement details
store_payer_volume	Store	Accumulates total USDC spent per payer
store_payer_count	Store	Counts payments per payer
store_recipient_volume	Store	Accumulates total USDC received per resource server
store_recipient_count	Store	Counts payments per recipient
store_facilitator_volume	Store	Accumulates total USDC volume per facilitator
store_facilitator_count	Store	Counts settlements per facilitator
store_facilitator_gas	Store	Tracks gas costs per facilitator
map_payer_stats	Map	Computes payer leaderboards and averages
map_recipient_stats	Map	Computes resource server revenue stats
map_facilitator_stats	Map	Computes facilitator economics (volume vs gas cost)
db_out	Map	Outputs DatabaseChanges for PostgreSQL sink

Contract Indexed

Contract	Address	Events
USDC (Base)	0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913	AuthorizationUsed, Transfer

Quick Start

# Stream settlements
substreams run x402-base-pulse map_x402_settlements \
  -e base-mainnet.streamingfast.io:443 \
  -s 29000000 -t +1000

# GUI mode
substreams gui x402-base-pulse map_x402_settlements \
  -e base-mainnet.streamingfast.io:443 \
  -s 29000000

# Sink to PostgreSQL
substreams-sink-sql run "psql://localhost/x402" \
  x402-base-pulse-v2.0.1.spkg \
  -e base-mainnet.streamingfast.io:443

SQL Output

Tables

Table	Key	Description
settlements	tx_hash-log_index	Every settlement with payer, recipient, amount, facilitator, gas
payers	payer_address	Aggregated spend and payment count per payer
recipients	recipient_address	Revenue and payment count per resource server
facilitators	facilitator_address	Volume settled, settlement count, total gas spent
daily_stats	date	Daily protocol-wide volume, participants, gas

Views

View	Description
top_payers	Ranked by total USDC spent
top_recipients	Ranked by total USDC received
facilitator_economics	Volume settled vs gas cost per facilitator
whale_payments	Payments > $100 USDC
recent_settlements	Latest 100 settlements

Build

cargo build --target wasm32-unknown-unknown --release
substreams pack substreams.yaml

References

• x402 Protocol -- Coinbase's HTTP 402 payment standard
• How It Works -- Settlement flow
• Network Support -- Supported tokens and chains
• EIP-3009 -- Transfer With Authorization
• x402 Source -- Protocol implementation

Network

• Chain: Base
• Start Block: 25,000,000
• Endpoint: base-mainnet.streamingfast.io:443