diff --git a/api/src/instruction.rs b/api/src/instruction.rs
index 5d00d43..bf0e6bd 100644
--- a/api/src/instruction.rs
+++ b/api/src/instruction.rs
@@ -50,8 +50,11 @@ pub enum OreInstruction {
 
     #[account(0, name = "ore_program", desc = "Ore program")]
     #[account(1, name = "signer", desc = "Signer", signer)]
-    #[account(2, name = "proof", desc = "Ore proof account", writable)]
-    #[account(3, name = "system_program", desc = "Solana system program")]
+    #[account(2, name = "miner", desc = "Address to be initialized as the miner")]
+    #[account(3, name = "payer", desc = "Account to pay for account creation", writable, signer)]
+    #[account(4, name = "proof", desc = "Ore proof account", writable)]
+    #[account(5, name = "system_program", desc = "Solana system program")]
+    #[account(6, name = "slot_hashes", desc = "Solana slot hashes sysvar")]
     Open = 4,
 
     #[account(0, name = "ore_program", desc = "Ore program")]
diff --git a/program/src/open.rs b/program/src/open.rs
index fc6e570..760642b 100644
--- a/program/src/open.rs
+++ b/program/src/open.rs
@@ -33,11 +33,13 @@ pub fn process_open<'a, 'info>(
     let args = OpenArgs::try_from_bytes(data)?;
 
     // Load accounts
-    let [signer, miner_info, proof_info, system_program, slot_hashes_info] = accounts else {
+    let [signer, miner_info, payer_info, proof_info, system_program, slot_hashes_info] = accounts
+    else {
         return Err(ProgramError::NotEnoughAccountKeys);
     };
     load_signer(signer)?;
     load_system_account(miner_info, false)?;
+    load_signer(payer_info)?;
     load_uninitialized_pda(
         proof_info,
         &[PROOF, signer.key.as_ref()],
@@ -54,7 +56,7 @@ pub fn process_open<'a, 'info>(
         8 + size_of::<Proof>(),
         &[PROOF, signer.key.as_ref(), &[args.bump]],
         system_program,
-        signer,
+        payer_info,
     )?;
     let clock = Clock::get().or(Err(ProgramError::InvalidAccountData))?;
     let mut proof_data = proof_info.data.borrow_mut();