September 30, 2026 · 7 min read
How Old Is 'finalized'? We Measured 62 Chains
eth_getBlockByNumber('finalized') ranges from instant to four hours across 62 EVM chains; five give no answer, one returns genesis. The table and code.
Read →Posts tagged #json-rpc
9 posts.
August 29, 2026 · 4 min read
trace_filter and trace_transaction: Beyond Receipts
Receipts show that a transaction succeeded; traces show what it did. How trace_transaction and trace_filter expose internal calls, where the Parity trace namespace actually works in 2026 (we probe it weekly — it's 11 of 54 EVM chains), and the param quirks that trip people up.
Read →August 28, 2026 · 4 min read
JSON-RPC Error Codes: Retry, Fix, or Accept?
-32601, -32000, code 3, HTTP 429 — every RPC error belongs to one of three families: try another node, fix your request, or accept the chain's answer. A field guide with real error payloads.
Read →June 8, 2026 · 5 min read
Arbitrum WebSocket Gotchas We Hit in Production
Connecting to Arbitrum over WebSocket the same way you connect to Ethereum mainnet will bite you. The sequencer has no public mempool, newHeads is a firehose, and reconnecting isn't enough. Here's what actually breaks and how to handle it.
Read →June 7, 2026 · 5 min read
What Is an RPC Endpoint? A 5-Minute Explainer
Every blockchain tutorial says 'connect to an RPC endpoint' and then moves on. Here's what one actually is, what the URL means, how a request works, and when you need a provider — in five minutes.
Read →June 4, 2026 · 7 min read
Multicall3 Cheat Sheet: One eth_call Does It All
Multicall3 lives at the same address on every EVM chain and turns 100 contract reads into one RPC call. Here's how it actually works, when to use which variant, and the gotchas that bite people in production.
Read →June 1, 2026 · 6 min read
How eth_getLogs Range Caps Bite in Production
Your indexer works fine until it hits a single dense block range, then everything stops. Here's the cap mechanics across providers, the adaptive chunking pattern that actually works, and the code to do it right.
Read →May 30, 2026 · 6 min read
Solana WebSocket vs HTTP RPC for Bots
Most Solana bots burn 80% of their RPC budget polling for state that WebSocket subscriptions would push to them for free. Here's when to use which, with the commitment-level gotchas that bite people in production.
Read →May 28, 2026 · 6 min read
JSON-RPC Batching: The 100× Speedup Devs Skip
Most dApps make 50 RPC calls when they could make one. Here's how JSON-RPC batching works, why ethers.js and viem already do most of it for you, and where you still have to think about it.
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