From an infrastructure perspective, “transaction decoding” is not about parsing bytes.
It is about reconstructing intent from execution artifacts.
On Ethereum, that intent is primarily encoded through ABIs and event logs.
On Solana, it emerges from instruction flows and account state mutations.
Treating these two systems as variations of the same decoding problem leads to lossy abstractions and incorrect analytics.
Before diving into implementation details, it is worth comparing the core primitives that each chain exposes to indexers and data pipelines.
Core differences in transaction decoding
Aspect: Primary semantic signal
Ethereum (EVM)
Event logs emitted during contract executions
Solana
Instructions executed by programs
Aspect: How user intent is expressed
Ethereum (EVM)
Function calls combined with structured event emissions
Solana
Ordered instruction sequence with explicit account inputs
Aspect: Role of logs / events
Ethereum (EVM)
Logs are first-class semantic artifacts designed for off-chain consumption
Solana
logMessages rarely includes helpful information for semantic artifacts
Aspect: Main decoding dependency
Ethereum (EVM)
Contract ABI (function and event definitions)
Without the ABI, decoding a transaction into meaningful semantic actions becomes extremely difficult, if not impossible.
Solana
Program interface (IDL when available) and instruction layout
Without the IDL/ instruction layout, decoding a transaction into meaningful semantic actions still possible in some situation but it’s not make sure we decode enough instructions
Aspect: Visibility of internal execution
Ethereum (EVM)
Internal calls are mostly opaque unless surfaced via logs
Solana
Inner instructions are explicitly exposed and indexed
Aspect: Native token movement
Ethereum (EVM)
Only direct native transfer are visible in transaction receipt.
Internal transaction need to trace_debug with archive node, it’s more complicated and expensive
Solana
SOL transfer, SOL balance change are exposed and indexed
Aspect: Semantic signal for action identification
Ethereum (EVM)
In many cases, the semantic meaning of a user action can be inferred from a single, well-defined event log emitted during execution.
Solana
Semantic decoding typically requires correlating the primary program instruction with one or more associated token transfer instructions to reconstruct the full intent.
Aspect: Related token identification
Ethereum (EVM)
Token addresses are directly exposed in event logs, allowing decoding logic to identify involved tokens without extra inference.
Solana
Transactions expose token accounts rather than the underlying token addresses.
Decoding requires mapping token accounts to their corresponding token mint to determine the actual tokens involved.
Aspect: Token metadata availability
Ethereum (EVM)
Token metadata such as name, symbol, and decimals is available on-chain via standard ERC-20/ERC-721 interfaces.
Solana
Only decimals are reliably stored on-chain.
Other metadata like name and symbol is typically stored off-chain (e.g., via metadata accounts in the Token Metadata program).
Aspect: Realtime subscription & backfill
Ethereum (EVM)
Websocket subscriptions (eth_subscribe) can filter logs by contract address and topic, allowing indexers to receive realtime updates.
Because logs are indexed and immutable, it is also straightforward to backfill historical data to decode a protocol quickly.
Solana
Websocket subscriptions (programSubscribe) can track realtime transactions affecting a program or account, but there is no topic-like filter.
Filtering must be done client-side by decoding instructions, and there is no native historical backfill, making full protocol reconstruction slower and more resource-intensive.
Aspect: Protocol-level event authenticity / instruction trust
Ethereum (EVM)
Early protocols like Uniswap V2/V3 emitted event logs directly from permissionless pools.
Combined with protocol clones, this made it difficult to distinguish legitimate protocol events from fake or malicious logs.
Modern protocols such as Balancer and Uniswap V4 mitigated this by emitting event logs through a single pool manager, centralizing the semantic signal and improving reliability for indexers.
Solana
All user actions interact directly with the protocol’s main program ID, similar to Balancer or Uniswap V4.
This design makes it practically impossible to fake user actions by crafting instructions, because malicious transactions cannot target the main program ID without breaking protocol integrity.
Aspect: Dependency on off-chain storage / database
Ethereum (EVM)
Most transactions can be fully decoded using only on-chain data, without relying on any off-chain storage or local database.
Exception: Protocols like Uniswap V4, Ekubo, and similar, require tracking pool token lists from the pool creation event.
Without storing this information locally, it is nearly impossible to query on-chain later to reconstruct the pool tokens and decode subsequent events.
Solana
All transactions can be decoded entirely using on-chain accounts and instruction data, without relying on any off-chain storage.
Since all user actions interact directly with the main program ID, full semantic intent is available on-chain, making decoding reliable without any database.
I hope this comparison of Ethereum and Solana transaction decoding from a technical perspective was helpful.
We’re continuously working on improving our understanding and decoding infrastructure, and your feedback is invaluable.
If you have thoughts, suggestions, or corrections, please leave a comment below — we’ll carefully review all input and update this article accordingly.
Thank you for reading!