The proposed Solana block footer identifies the software client the block producer says it used; it is not the same as the block’s leader, which identifies the responsible validator. The key field is blockUserAgent. Because SIMD-0307 is marked Review, treat this as a proposed format—not a feature guaranteed to appear in every RPC response or explorer.
What the block footer tells you
Solana SIMD-0307, “Add Block Footer,” proposes a marker after the last entry batch in a block. Its payload contains a footer version, a construction-start timestamp, and a variable-length UTF-8 user-agent string. In the proposal’s RPC example, the fields appear under a footer object as blockProducerTimeNanos and blockUserAgent. SIMD-0307
As an Amazon Associate I earn from qualifying purchases.
The proposal defines a client as “the software run by leaders to interface with a solana cluster.” In practical terms, the footer is meant to add a producer-declared software identity to historical block data, alongside a finer-grained indication of when block construction began.
What’s actually slowing this PC down?
Pick the symptom - the matching free tool is one click away.
How to read a footer
- Check whether the response has a
footerobject. SIMD-0307’s design describes a footer request parameter and says footer fields are included by default, but the proposal’s sample does not establish that RPC providers have implemented it. Check the actual response and your provider’s documentation. - Read the first entry in
blockUserAgent. The format is<product>/<product-version> <comment>; the first product/version entry names the declared base client. - Inspect the parenthetical comment. It can record producer-supplied fork or feature details. SIMD-0307’s example is
agave/v2.2.15 (jito; double0; some-mod/v1.2.3). - Check for further product/version entries. These can name complementary software used by the producer, such as a scheduler; they do not replace the base-client entry.
- Interpret
blockProducerTimeNanosas construction start. Under the proposal, this is a nanosecond Unix timestamp for when the producer began constructing the block, from the leader’s point of view. It is not simply the ordinary block timestamp displayed by an explorer.
Which client names can appear?
SIMD-0307 lists agave, frankendancer, and firedancer as base client options. A fork such as jito-agave can use a base client label and express fork details in the parenthetical comment. Compare the base name and version first, then the comment and any additional entries; the format conveys what the producer declares, not a standardized inventory of every binary component.
#1 Best Overall
Names can also describe mixed software composition. Firedancer’s documentation describes Frankendancer as a development configuration combining Firedancer’s networking layer with Agave runtime and consensus. Therefore, a Frankendancer label should not be read as proof that every component is an independent Firedancer implementation. Firedancer documentation
Client versus leader: two different questions
A leader is the validator responsible for producing a block; a client is the software that validator runs. An explorer’s leader field answers who produced it in validator-identity terms, not which implementation the validator used. Solscan’s block-details documentation lists information such as leader, timestamp, blockhash, rewards, transaction count, and previous blockhash. A leader public key alone cannot distinguish Agave, Firedancer, Frankendancer, or a fork. Solscan documentation
Rank #2
Similarly, SolanaFM’s documented block API example includes a producer public key and common block information, but does not show SIMD-0307’s proposed user-agent footer. Do not infer footer support from an explorer’s leader or producer field; verify the RPC payload itself or consult the provider’s documentation. SolanaFM block API documentation
The Tool Desk
Outbyte Driver Updater FREEScan for outdated or missing drivers - takes under a minuteDriver Scan →Outbyte PC Repair FREERepair Windows errors before they cause bigger problemsFix Now →How much should you trust the client string?
SIMD-0307 says producers populate footer fields unilaterally, without enforced content constraints. Accordingly, blockUserAgent is producer-declared metadata, not a cryptographic attestation of the exact binary, build, or configuration that ran. It can help with monitoring, benchmarking, and historical analysis, but it should not alone be treated as proof of software identity.
The proposal motivates a static footer partly by noting that gossip-based information can be ephemeral and may omit scheduler, modification, or configuration detail; it also says vote timestamps have one-second granularity and will be removed with Alpenglow. Those are SIMD-0307’s stated motivations, not independent confirmation here of current network behavior. The proposal was created June 17, 2025, and its repository metadata lists its status as Review. SIMD-0307
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Comparing two footer values
- Compare the base client label and version.
- Compare parenthetical fork or feature details without assuming they are independently verified.
- Note any further complementary software entries.
- Compare construction-start timestamps as producer timing metadata, not as an explorer’s ordinary block time.
If one record is an explorer page rather than a footer, keep software attribution separate from validator identity and ordinary block timestamp. SIMD-0307 and the cited block documentation do not establish a current client-share statistic, so these fields should not be used to infer network-wide client percentages.
Quick Recap
Best Value
Rank #4
- Brand New in box. The product ships with all relevant accessories
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
Free tools Windows power users keep installed
One-click scans. No signup required.
