484 articles · 68 blockchains · 127 topics
Practical tutorials, troubleshooting guides and deep dives on Bitcoin, Ethereum, Solana, layer 2s and every chain in between — written by developers who ship on them.
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Layer 1The original cryptocurrency and proof-of-work blockchain.
39 articles →
Layer 1The programmable blockchain behind smart contracts and DeFi.
27 articles →
Layer 1A high-throughput layer 1 built for low-latency apps.
2 articles →
Layer 2Ethereum scaling: the Polygon PoS chain and ZK technology.
1 article →
Layer 2An optimistic rollup that scales Ethereum.
1 article →
Layer 2The OP Stack rollup and the Superchain behind it.
0 articles →
Layer 2Coinbase's OP Stack layer 2.
1 article →
Layer 1The EVM chain of the BNB ecosystem.
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Editor's picks
ArbitrumIntermediateRollups execute off-chain and post data to Ethereum. Optimistic rollups like Arbitrum assume validity unless a fault proof wins during a challenge window; ZK rollups post a validity proof per batch.
In this article
· 5 min read
EthereumIntermediateUpdate state before any external call (checks-effects-interactions), add nonReentrant to every function sharing that state, and treat token hooks and user-supplied addresses as external calls.
#security#smart-contracts#solidity
BitcoinBeginnerMiners hash an 80-byte block header until its double SHA-256 falls below a target. Difficulty retargets every 2016 blocks, and nodes follow the chain with the most cumulative work.
#basics#consensus#mining
Fresh commits
SuiIntermediateMove treats assets as typed resources that can't be copied or dropped, stores state with owners instead of in contract mappings, uses signers and capabilities for access control, and avoids classic reentrancy.
#move#security#smart-contracts
EthereumIntermediateMEV is profit from ordering transactions. A sandwich attack front-runs and back-runs a public swap, capped by its slippage. Use tight minimum outputs from fresh quotes and private RPCs.
#defi#mev#security
EthereumIntermediateApprove is safe; unlimited, forgotten allowances and unread permit signatures are not. Approve exact amounts, use permit with short deadlines, read every typed-data signature, and revoke old approvals.
#security#tokens#wallets
BaseIntermediateERC-4337 makes user accounts smart contracts via UserOperations, bundlers, an EntryPoint and paymasters, enabling batching, gas sponsorship and recovery. EIP-7702 lets existing EOAs delegate to such code.
#account-abstraction#smart-contracts#wallets
GeneralIntermediateA bridge is only as safe as whatever verifies cross-chain messages. Most major hacks came from stolen validator keys, verification bugs, or bad upgrades, not the chains themselves.
#bridges#security
EthereumIntermediateStorage dominates gas costs: pack variables, cache storage reads, use constant, immutable, calldata and custom errors, emit events for off-chain data, and measure every change with forge snapshot.
#gas-&-fees#performance#solidity
Learning paths
LEVEL 01
Blocks, keys, wallets and your first transaction. Build intuition that lasts.
Browse beginner articles →
LEVEL 02
Smart contracts, gas, testing and the trade-offs between chains and layer 2s.
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LEVEL 03
Consensus, MEV, security audits, proxies and protocol internals.
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