Reference

Solana programs

Three Anchor programs carry Vouch verdicts on Solana: pof-gate turns attestations into receipts, pof-credit lends against receipts, and pof-reserve keeps an attested reserves feed. Every instruction, account and error below is generated from the programs’ IDLs.

On this page

How they fit together
The attestation message
How signatures are checked
pof-gate
pof-credit
pof-reserve
Deploying

#How they fit together

Solana's Ed25519 precompile checks the signature; pof-gate then reads that instruction back through the Instructions sysvar and checks that its signer is allowlisted and its message is exactly the one being submitted.

Seeds in brackets. A receipt is keyed by the proof id, so one proof makes one receipt; a credit line is keyed by the receipt and the borrower; a feed is keyed by its audience, and its mint's authority is the feed itself.

Program	Role	Tests
pof-gate	Ed25519 attestations by introspection, k of n; one receipt per proof, bound to a wallet; consumption by consumer-program PDAs only.	replay, wrong key, other message, foreign offsets, late or truncated signatures, stale/future/expired/invalid/unknown, malformed, bound account only, threshold 2 of 3, admin and attestor-set rules, initialize by the upgrade authority only
pof-credit	Pools, credit lines and draws against receipts, with freshness and refreshes.	happy path, draw needs the borrower and the pool mint, one line per receipt, a line per proof, freshness, refresh rules, pool floor and window, mint authority
pof-reserve	An attested reserves feed and Secure Mint.	publish then mint within the reserves, only the issuer mints, a stale feed mints nothing until refreshed, publish refuses what it must

26 LiteSVM tests run in CI against the compiled programs.

#The attestation message

139 bytes, little-endian, domain-separated. The attestor signs it with Ed25519; pof-gate parses exactly this layout.

The attestor signs these 139 bytes with Ed25519 only for a Valid verdict on a proof bound to a Solana account. pof-gate parses exactly this layout, checks the domain, the verdict and the claim kind, that the slot is within max_age_slots and that expires_at is in the future.

#How signatures are checked

Programs cannot run Ed25519 cheaply themselves, so the transaction carries one Ed25519 precompile instruction per attestor signature before the program’s instruction. The program reads those instructions through the Instructions sysvar and counts a signer only when:

the instruction comes before the program’s own instruction;
every offset in it is u16::MAX, meaning the key, message and signature are inside that same instruction (no pointing into other data);
the key is on the allowlist and has not been counted already;
the signed message is byte for byte the one being submitted.

Only when the count reaches the threshold does the program act. The runtime has already failed the transaction if any signature was bad.

#pof-gate

Program id A6WmRTgEAHC9GHstaj9oD8woVNRw9jgu31bpKVREXn8C on devnet. 4 instructions, 2 account types, 15 errors.

Instructions

pof_gate::initialize(attestors: Vec<pubkey>, threshold: u8, max_age_slots: u64)

Account	Flags	Seeds / notes
`config`	writable · PDA	`["config"]`
`admin`	writable · signer	Must be the program's upgrade authority: otherwise anyone could create the config first and make themselves admin.
`program`	fixed	A6WmRTgEAHC9GHstaj9oD8woVNRw9jgu31bpKVREXn8C
`program_data`	—
`system_program`	fixed	11111111111111111111111111111111

pof_gate::mark_consumed()

Called by a consumer program (by CPI) to spend a receipt exactly once. The beneficiary must sign, so nobody can burn someone else's receipt. The consumer program must sign too, through its `[b"consumer"]` PDA, so the program recorded in `consumed_by` is the one that called.

Account	Flags	Seeds / notes
`receipt`	writable · PDA	`["receipt", receipt.subject]`
`beneficiary`	signer
`consumer`	signer · PDA	`["consumer"]`
`consumer_program`	—

pof_gate::set_attestors(attestors: Vec<pubkey>, threshold: u8, max_age_slots: u64)

Account	Flags	Seeds / notes
`config`	writable · PDA	`["config"]`
`admin`	signer

pof_gate::submit_attestation(subject: [u8; 32], message: bytes)

Checks, cheapest first: layout and domain · verdict · claim kind · freshness · expiry · signatures (introspection) · create the receipt (fails if it exists: replay protection).

Account	Flags	Seeds / notes
`config`	PDA	`["config"]`
`receipt`	writable · PDA	`["receipt", subject]`
`payer`	writable · signer
`instructions`	fixed	Sysvar1nstructions1111111111111111111111111
`system_program`	fixed	11111111111111111111111111111111

Accounts

ClaimReceipt

Field	Type	Notes
`subject`	`[u8; 32]`	blake2b(statement): one proof, one receipt.
`beneficiary`	`pubkey`	The Solana account the proof is bound to.
`audience`	`[u8; 32]`	blake2b of the verifier identifier the proof was made for.
`claim_kind`	`u8`
`claim_value`	`u64`
`anchor_height`	`u32`
`expires_at`	`i64`
`attested_slot`	`u64`
`signers`	`u8`
`created_slot`	`u64`
`consumed`	`bool`
`consumed_by`	`pubkey`	The consumer program that spent it.
`bump`	`u8`

Config

Field	Type	Notes
`admin`	`pubkey`
`attestors`	`Vec<pubkey>`
`threshold`	`u8`
`max_age_slots`	`u64`
`bump`	`u8`

Events

Event	Fields
`AttestorsChanged`	threshold, count
`ReceiptConsumed`	subject, consumer
`ReceiptCreated`	subject, beneficiary, claim_value, anchor_height

Errors

Code	Name	Message
6000	`BadLength`	attestation must be 139 bytes
6001	`BadDomain`	attestation is not domain-separated as POF-ATTEST-v1
6002	`BadExpiry`	expiry out of range
6003	`NotValid`	only Valid verdicts are accepted
6004	`UnknownClaim`	unknown claim kind
6005	`Stale`	attestation is older than max_age_slots, or from the future
6006	`Expired`	the proof behind this attestation has expired
6007	`BadEd25519`	malformed Ed25519 instruction
6008	`ForeignOffsets`	an Ed25519 signature entry points outside its own instruction
6009	`NotEnoughSignatures`	not enough allowlisted attestors signed this exact message
6010	`AlreadyConsumed`	receipt already consumed
6011	`WrongBeneficiary`	signer is not the account the proof is bound to
6012	`BadAttestorSet`	attestor set must be 1–8 distinct keys with 1 ≤ threshold ≤ count
6013	`SubjectMismatch`	the subject argument does not match the attestation
6014	`NotUpgradeAuthority`	only the program's upgrade authority can initialize it

#pof-credit

Program id J6ewFZAzcTkbVsYNBrcZvzdBtTTUK5UrpqCg9jiNyra1 on devnet. 5 instructions, 2 account types, 9 errors.

Instructions

pof_credit::draw(amount: u64)

Account	Flags	Seeds / notes
`pool`	PDA	`["pool", pool.mint]`
`line`	writable · PDA	`["line", line.opened_against, borrower]`
`borrower`	signer
`vault`	writable
`borrower_token`	writable
`token_program`	fixed	TokenkegQfeZyiNwAJbNbGKPFXCWuBvf9Ss623VQ5DA

pof_credit::init_pool(audience: [u8; 32], required_zatoshi: u64, line_limit: u64)

Account	Flags	Seeds / notes
`pool`	writable · PDA	`["pool", mint]`
`mint`	—	The pool's creator must control the mint: nobody can open a pool under someone else's asset.
`vault`	writable · PDA	`["vault", pool]`
`authority`	writable · signer
`token_program`	fixed	TokenkegQfeZyiNwAJbNbGKPFXCWuBvf9Ss623VQ5DA
`system_program`	fixed	11111111111111111111111111111111

pof_credit::open_line()

Account	Flags	Seeds / notes
`pool`	PDA	`["pool", pool.mint]`
`receipt`	writable
`line`	writable · PDA	`["line", receipt.subject, borrower]`
`borrower`	signer
`payer`	writable · signer	Pays the line's rent, so a borrower needs no SOL (in the demo, the relayer).
`consumer`	PDA	`["consumer"]`
`consumer_program`	fixed	This program, named to pof-gate as the consumer.
`gate_program`	fixed	A6WmRTgEAHC9GHstaj9oD8woVNRw9jgu31bpKVREXn8C
`system_program`	fixed	11111111111111111111111111111111

pof_credit::refresh_line()

Present a new proof for an open line. The receipt must meet the pool's terms like the one that opened the line, and its anchor must be no older than the line's last.

Account	Flags	Seeds / notes
`pool`	PDA	`["pool", pool.mint]`
`line`	writable · PDA	`["line", line.opened_against, borrower]`
`receipt`	writable
`borrower`	signer
`consumer`	PDA	`["consumer"]`
`consumer_program`	fixed	This program, named to pof-gate as the consumer.
`gate_program`	fixed	A6WmRTgEAHC9GHstaj9oD8woVNRw9jgu31bpKVREXn8C

pof_credit::set_freshness(fresh_secs: i64, min_anchor_height: u32)

The pool's authority sets how long a proof keeps a line drawable, and the oldest Zcash anchor the pool accepts when a line is opened or refreshed.

Account	Flags	Seeds / notes
`pool`	writable · PDA	`["pool", pool.mint]`
`authority`	signer

Accounts

CreditLine

Field	Type	Notes
`pool`	`pubkey`
`borrower`	`pubkey`
`limit`	`u64`
`drawn`	`u64`
`opened_against`	`[u8; 32]`	The receipt subject (proof id) this line was opened against.
`anchor_height`	`u32`	The anchor of the latest proof: the one that opened the line, or the last refresh.
`opened_slot`	`u64`
`bump`	`u8`
`fresh_until`	`i64`	Draws are refused from this time on, until a refresh.
`refreshed_against`	`[u8; 32]`	The receipt subject of the latest proof.
`refreshes`	`u32`

Pool

Field	Type	Notes
`authority`	`pubkey`
`mint`	`pubkey`
`vault`	`pubkey`
`audience`	`[u8; 32]`	blake2b("pof-audience:" ‖ identifier). Proofs for anyone else are refused.
`required_zatoshi`	`u64`
`line_limit`	`u64`	Per-line limit, in the mint's base units.
`bump`	`u8`
`fresh_secs`	`i64`	How long a proof keeps a line drawable, in seconds.
`min_anchor_height`	`u32`	The oldest Zcash anchor height accepted when a line is opened or refreshed.

Events

Event	Fields
`FreshnessChanged`	pool, fresh_secs, min_anchor_height
`LineOpened`	line, borrower, limit, against
`LineRefreshed`	line, against, anchor_height, fresh_until

Errors

Code	Name	Message
6000	`BadTerms`	terms must be non-zero
6001	`WrongAudience`	the proof was made for a different verifier
6002	`BelowThreshold`	the proven amount is below this pool's threshold
6003	`NotBoundToSigner`	the signer is not the account the proof is bound to
6004	`ReceiptConsumed`	this receipt has already funded a line
6005	`ProofExpired`	the proof has expired
6006	`OverLimit`	draw exceeds the line's limit
6007	`AnchorTooOld`	the proof is older than this pool accepts: present a newer one
6008	`NeedsFreshProof`	the line's latest proof is no longer fresh: refresh it with a new proof

#pof-reserve

112 bytes, little-endian. The attestor signs it after verify_batch; pof-reserve::publish parses exactly this layout.

Program id 5Q26Tjcd4equ5te5hF15eG4xK6uvkbZtKkEeqdf535h9 on devnet. 5 instructions, 2 account types, 17 errors.

Instructions

pof_reserve::init_feed(audience: [u8; 32], heartbeat_slots: u64, issuer: pubkey)

A feed for one verifier identifier (its audience hash), with its own demo token that only `issuer` may mint. Admin only.

Account	Flags	Seeds / notes
`config`	PDA	`["config"]`
`feed`	writable · PDA	`["feed", audience]`
`mint`	writable · PDA	`["mint", feed]`
`admin`	writable · signer
`token_program`	fixed	TokenkegQfeZyiNwAJbNbGKPFXCWuBvf9Ss623VQ5DA
`system_program`	fixed	11111111111111111111111111111111

pof_reserve::initialize(attestors: Vec<pubkey>, threshold: u8, max_age_slots: u64)

Account	Flags	Seeds / notes
`config`	writable · PDA	`["config"]`
`admin`	writable · signer	Must be the program's upgrade authority: otherwise anyone could create the config first.
`program`	fixed	5Q26Tjcd4equ5te5hF15eG4xK6uvkbZtKkEeqdf535h9
`program_data`	—
`system_program`	fixed	11111111111111111111111111111111

pof_reserve::publish(message: bytes)

Write a signed batch verdict to the feed. Anyone may submit it; only the allowlisted attestors' signatures make it count. A feed never goes back to an older anchor.

Account	Flags	Seeds / notes
`config`	PDA	`["config"]`
`feed`	writable · PDA	`["feed", feed.audience]`
`instructions`	fixed	Sysvar1nstructions1111111111111111111111111

pof_reserve::secure_mint(amount: u64)

Secure Mint: the feed's token mints only while the feed is fresh and the supply stays within the proven reserves. The issuer signs.

Account	Flags	Seeds / notes
`feed`	PDA	`["feed", feed.audience]`
`mint`	writable
`to`	writable
`issuer`	signer
`token_program`	fixed	TokenkegQfeZyiNwAJbNbGKPFXCWuBvf9Ss623VQ5DA

pof_reserve::set_attestors(attestors: Vec<pubkey>, threshold: u8, max_age_slots: u64)

Account	Flags	Seeds / notes
`config`	writable · PDA	`["config"]`
`admin`	signer

Accounts

Config

Field	Type	Notes
`admin`	`pubkey`
`attestors`	`Vec<pubkey>`
`threshold`	`u8`
`max_age_slots`	`u64`
`bump`	`u8`

Feed

Field	Type	Notes
`audience`	`[u8; 32]`	blake2b of the verifier identifier the reserves were proven to.
`issuer`	`pubkey`	Who may mint the feed's token.
`mint`	`pubkey`
`heartbeat_slots`	`u64`
`scope`	`[u8; 32]`
`total_zatoshi`	`u64`
`members`	`u16`
`anchor_height`	`u32`
`nc_height`	`u32`
`expires_at`	`i64`
`updated_slot`	`u64`
`publishes`	`u32`
`bump`	`u8`

Events

Event	Fields
`FeedUpdated`	audience, total_zatoshi, anchor_height, signers
`SecureMinted`	audience, amount, supply

Errors

Code	Name	Message
6000	`BadLength`	a reserve message is 112 bytes
6001	`BadDomain`	message is not domain-separated as POF-RESERVE-v1
6002	`BadExpiry`	expiry out of range
6003	`BadMessage`	malformed reserve message
6004	`BadEd25519`	malformed Ed25519 instruction
6005	`ForeignOffsets`	an Ed25519 signature entry points outside its own instruction
6006	`NotEnoughSignatures`	not enough allowlisted attestors signed this exact message
6007	`Stale`	the attestation is older than max_age_slots, or from the future
6008	`Expired`	the proofs behind these reserves have expired
6009	`WrongAudience`	the reserves were proven to another verifier than this feed
6010	`OlderAnchor`	a feed never goes back to an older anchor
6011	`NeverPublished`	the feed has never been published
6012	`StaleFeed`	the feed is stale: no publish within its heartbeat
6013	`OverReserves`	minting this would exceed the proven reserves
6014	`BadHeartbeat`	heartbeat must be at least one slot
6015	`BadAttestorSet`	attestor set must be 1–8 distinct keys with 1 ≤ threshold ≤ count
6016	`NotUpgradeAuthority`	only the program's upgrade authority can initialize it

#Deploying

Shell

POF_ATTEST_URL=https://<attestor> [ATTESTORS=<b58,…>] ./scripts/deploy-devnet.sh

The script builds and deploys under the fixed program ids, copies the IDLs to the site, allowlists the attestor (read from /v1/pubkey when ATTESTORS is unset), creates the credit pool and the reserves feed, and prints the site’s environment. The admin keeps the upgrade authority, which initialize requires. Local validators load pof-gate as an upgradeable program for the same reason.