diff --git a/Cargo.lock b/Cargo.lock
index 07e543e..8ed1112 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1325,6 +1325,7 @@ dependencies = [
  "solana-program",
  "spl-associated-token-account",
  "spl-token 4.0.2",
+ "spl-token-2022 7.0.0",
  "steel",
 ]
 
diff --git a/Cargo.toml b/Cargo.toml
index 6a82026..5f394c4 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -29,6 +29,7 @@ solana-program = "^2.1"
 solana-client = "^2.1"
 solana-sdk = "^2.1"
 spl-token = { version = "^4", features = ["no-entrypoint"] }
+spl-token-2022 = "^7"
 spl-associated-token-account = { version = "^6", features = [ "no-entrypoint" ] } 
 steel = { features = ["spl"], version = "4.0" }
 thiserror = "1.0.57"
diff --git a/README.md b/README.md
index 6f67b88..f94cda5 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,6 @@
 # ORE
 
-**Digital gold, accelerated.**
+**Mine blockspace. Trade hashpower. Win rewards.**
 
 ## API
 - [`Consts`](api/src/consts.rs) – Program constants.
@@ -9,18 +9,28 @@
 - [`Instruction`](api/src/instruction.rs) – Declared instructions and arguments.
 
 ## Instructions
-- [`Bury`](program/src/bury.rs) - Swap committed tokens into ORE and burns it.
-- [`Close`](program/src/close.rs) - Close a commit account.
-- [`Deploy`](program/src/deploy.rs) - Deploy capital to mine the current block.
-- [`Initialize`](program/src/initialize.rs) - Initialize the program.
-- [`Payout`](program/src/payout.rs) - Payout the block reward to the winning commit.
-- [`Reset`](program/src/reset.rs) - Start the next block.
+
+#### Mine
+- [`Open`](program/src/open.rs) - Opens a new block for mining.
+- [`Close`](program/src/close.rs) - Closes a block and pays out rewards.
+- [`Mine`](program/src/mine.rs) - Mines the current block by computing hashes.
+
+#### Stake
+- [`Deposit`](program/src/deposit.rs) - Deposits stake into a miner account.
+- [`Withdraw`](program/src/withdraw.rs) - Withdraws stake from a miner account.
+- [`Free`](program/src/free.rs) - Frees up miner capacity after block ends.
+
+#### Trade
+- [`Buy`](program/src/buy.rs) - Buys hash tokens from the market.
+- [`Sell`](program/src/sell.rs) - Sells hash tokens to the market.
 
 ## State
-- [`Block`](api/src/state/block.rs) - A singleton account tracking rounds of commits.
-- [`Proof`](api/src/state/proof.rs) - (Deprecated) An account which tracks a miner's current hash and current stake.
-- [`Treasury`](api/src/state/treasury.rs) – The mint authority on the ORE token.
-- [`Commit`](api/src/state/commit.rs) - Capital deployed by a miner in the current block.
+- [`Block`](api/src/state/block.rs) - A period of time for mining.
+- [`Config`](api/src/state/config.rs) - Global program configuration.
+- [`Market`](api/src/state/market.rs) - Hashpower market for a given block.
+- [`Miner`](api/src/state/miner.rs) - A user's mining and staking state.
+- [`Receipt`](api/src/state/receipt.rs) - Tracks a miner's deployed capital.
+- [`Treasury`](api/src/state/treasury.rs) - The mint authority on the ORE token.
 
 
 ## Tests
diff --git a/api/src/instruction.rs b/api/src/instruction.rs
index 348ea96..7882b8a 100644
--- a/api/src/instruction.rs
+++ b/api/src/instruction.rs
@@ -3,19 +3,19 @@ use steel::*;
 #[repr(u8)]
 #[derive(Clone, Copy, Debug, Eq, PartialEq, TryFromPrimitive)]
 pub enum OreInstruction {
-    // Block
+    // Mine
     Open = 0,
     Close = 1,
     Mine = 2,
 
-    // Market
-    Buy = 3,
-    Sell = 4,
-
     // Stake
-    Deposit = 5,
-    Withdraw = 6,
-    Free = 7,
+    Deposit = 3,
+    Withdraw = 4,
+    Free = 5,
+
+    // Trade
+    Buy = 6,
+    Sell = 7,
 }
 
 #[repr(C)]
@@ -34,6 +34,22 @@ pub struct Mine {
     pub amount: [u8; 8],
 }
 
+#[repr(C)]
+#[derive(Clone, Copy, Debug, Pod, Zeroable)]
+pub struct Deposit {
+    pub amount: [u8; 8],
+}
+
+#[repr(C)]
+#[derive(Clone, Copy, Debug, Pod, Zeroable)]
+pub struct Withdraw {
+    pub amount: [u8; 8],
+}
+
+#[repr(C)]
+#[derive(Clone, Copy, Debug, Pod, Zeroable)]
+pub struct Free {}
+
 #[repr(C)]
 #[derive(Clone, Copy, Debug, Pod, Zeroable)]
 pub struct Buy {}
@@ -42,23 +58,11 @@ pub struct Buy {}
 #[derive(Clone, Copy, Debug, Pod, Zeroable)]
 pub struct Sell {}
 
-#[repr(C)]
-#[derive(Clone, Copy, Debug, Pod, Zeroable)]
-pub struct Deposit {}
-
-#[repr(C)]
-#[derive(Clone, Copy, Debug, Pod, Zeroable)]
-pub struct Withdraw {}
-
-#[repr(C)]
-#[derive(Clone, Copy, Debug, Pod, Zeroable)]
-pub struct Free {}
-
 instruction!(OreInstruction, Open);
 instruction!(OreInstruction, Close);
 instruction!(OreInstruction, Mine);
-instruction!(OreInstruction, Buy);
-instruction!(OreInstruction, Sell);
 instruction!(OreInstruction, Deposit);
 instruction!(OreInstruction, Withdraw);
 instruction!(OreInstruction, Free);
+instruction!(OreInstruction, Buy);
+instruction!(OreInstruction, Sell);
diff --git a/api/src/state/market.rs b/api/src/state/market.rs
index 4c92d5d..bfae8f6 100644
--- a/api/src/state/market.rs
+++ b/api/src/state/market.rs
@@ -6,7 +6,10 @@ use super::OreAccount;
 #[derive(Clone, Copy, Debug, PartialEq, Pod, Zeroable)]
 pub struct Market {
     /// The id of the block this market is associated with.
-    pub block_id: u64,
+    pub id: u64,
+
+    /// Mint of the hash token.
+    pub mint: Pubkey,
 }
 
 // TODO Bonding curve stuff
diff --git a/api/src/state/miner.rs b/api/src/state/miner.rs
index e62ad94..4bfec1a 100644
--- a/api/src/state/miner.rs
+++ b/api/src/state/miner.rs
@@ -11,8 +11,8 @@ pub struct Miner {
     /// The ID of the last block this miner mined in.
     pub block_id: u64,
 
-    /// The amount of ORE this miner can deploy into hashpower markets.
-    pub capacity: u64,
+    /// The amount of ORE this miner has deployed into hashpower markets.
+    pub deployed: u64,
 
     /// The hash of the last block this miner mined in.
     pub hash: [u8; 32],
diff --git a/api/src/state/treasury.rs b/api/src/state/treasury.rs
index 2268ae0..c8ccaf4 100644
--- a/api/src/state/treasury.rs
+++ b/api/src/state/treasury.rs
@@ -6,6 +6,9 @@ use super::OreAccount;
 /// the program's global token account.
 #[repr(C)]
 #[derive(Clone, Copy, Debug, PartialEq, Pod, Zeroable)]
-pub struct Treasury {}
+pub struct Treasury {
+    /// The total amount of ORE that has been staked.
+    pub total_stake: u64,
+}
 
 account!(OreAccount, Treasury);
diff --git a/program/Cargo.toml b/program/Cargo.toml
index f180729..0cf106f 100644
--- a/program/Cargo.toml
+++ b/program/Cargo.toml
@@ -25,6 +25,7 @@ ore-api.workspace = true
 ore-boost-api.workspace = true
 solana-program.workspace = true
 spl-token.workspace = true
+spl-token-2022.workspace = true
 spl-associated-token-account.workspace = true
 steel.workspace = true
 
diff --git a/program/src/buy.rs b/program/src/buy.rs
index e69de29..c41410a 100644
--- a/program/src/buy.rs
+++ b/program/src/buy.rs
@@ -0,0 +1,23 @@
+use ore_api::prelude::*;
+use steel::*;
+
+/// Buy hashpower.
+pub fn process_buy(accounts: &[AccountInfo<'_>], _data: &[u8]) -> ProgramResult {
+    // Load accounts.
+    let clock = Clock::get()?;
+    let [signer_info, block_info, market_info, miner_info, recipient_info, system_program, token_program] =
+        accounts
+    else {
+        return Err(ProgramError::NotEnoughAccountKeys);
+    };
+    signer_info.is_signer()?;
+    let block = block_info
+        .as_account_mut::<Block>(&ore_api::ID)?
+        .assert_mut(|b| clock.slot >= b.start_slot + 1500)?;
+    system_program.is_program(&system_program::ID)?;
+    token_program.is_program(&spl_token::ID)?;
+
+    // TODO Buy hash tokens
+
+    Ok(())
+}
diff --git a/program/src/close.rs b/program/src/close.rs
index e69de29..22e140b 100644
--- a/program/src/close.rs
+++ b/program/src/close.rs
@@ -0,0 +1,69 @@
+use ore_api::prelude::*;
+use steel::*;
+
+/// Closes a block.
+pub fn process_close(accounts: &[AccountInfo<'_>], _data: &[u8]) -> ProgramResult {
+    // Load accounts.
+    let clock = Clock::get()?;
+    let [signer_info, block_info, market_info, market_hash_info, market_ore_info, mint_hash_info, mint_ore_info, recipient_info, treasury_info, system_program, token_program] =
+        accounts
+    else {
+        return Err(ProgramError::NotEnoughAccountKeys);
+    };
+    signer_info.is_signer()?;
+    let block = block_info
+        .as_account_mut::<Block>(&ore_api::ID)?
+        .assert_mut(|b| clock.slot >= b.start_slot + 1500)?;
+    let market = market_info
+        .as_account_mut::<Market>(&ore_api::ID)?
+        .assert_mut(|m| m.id == block.id)?;
+    let market_hash =
+        market_hash_info.as_associated_token_account(market_info.key, mint_hash_info.key)?;
+    let market_ore =
+        market_ore_info.as_associated_token_account(market_info.key, mint_ore_info.key)?;
+    mint_hash_info.has_address(&market.mint)?;
+    mint_ore_info.has_address(&MINT_ADDRESS)?;
+    system_program.is_program(&system_program::ID)?;
+    token_program.is_program(&spl_token::ID)?;
+
+    // Payout block reward.
+    if block.best_miner != Pubkey::default() {
+        recipient_info.as_associated_token_account(&block.best_miner, &MINT_ADDRESS)?;
+        mint_to_signed(
+            mint_ore_info,
+            recipient_info,
+            treasury_info,
+            token_program,
+            block.reward,
+            &[TREASURY],
+        )?;
+    }
+
+    // Burn hash tokens.
+    burn_signed(
+        market_hash_info,
+        mint_hash_info,
+        market_info,
+        token_program,
+        market_hash.amount(),
+        &[MARKET, &market.id.to_le_bytes()],
+    )?;
+
+    // Burn ORE liquidity.
+    burn_signed(
+        market_ore_info,
+        mint_ore_info,
+        market_info,
+        token_program,
+        market_ore.amount(),
+        &[MARKET, &market.id.to_le_bytes()],
+    )?;
+
+    // Close block.
+    block_info.close(signer_info)?;
+
+    // Close market.
+    market_info.close(signer_info)?;
+
+    Ok(())
+}
diff --git a/program/src/deposit.rs b/program/src/deposit.rs
index e69de29..76cf0fc 100644
--- a/program/src/deposit.rs
+++ b/program/src/deposit.rs
@@ -0,0 +1,39 @@
+use ore_api::prelude::*;
+use steel::*;
+
+/// Deposits stake.
+pub fn process_deposit(accounts: &[AccountInfo<'_>], data: &[u8]) -> ProgramResult {
+    // Parse data.
+    let args = Deposit::try_from_bytes(data)?;
+    let amount = u64::from_le_bytes(args.amount);
+
+    // Load accounts.
+    let [signer_info, miner_info, sender_info, treasury_info, treasury_tokens_info, token_program] =
+        accounts
+    else {
+        return Err(ProgramError::NotEnoughAccountKeys);
+    };
+    signer_info.is_signer()?;
+    let miner = miner_info
+        .as_account_mut::<Miner>(&ore_api::ID)?
+        .assert_mut(|m| m.authority == *signer_info.key)?;
+    sender_info.as_associated_token_account(&signer_info.key, &MINT_ADDRESS)?;
+    let treasury = treasury_info.as_account_mut::<Treasury>(&ore_api::ID)?;
+    treasury_tokens_info.as_associated_token_account(&treasury_info.key, &MINT_ADDRESS)?;
+    token_program.is_program(&spl_token::ID)?;
+
+    // Update account state.
+    miner.stake += amount;
+    treasury.total_stake += amount;
+
+    // Execute transfer.
+    transfer(
+        signer_info,
+        sender_info,
+        treasury_tokens_info,
+        token_program,
+        amount,
+    )?;
+
+    Ok(())
+}
diff --git a/program/src/free.rs b/program/src/free.rs
index e69de29..f19e026 100644
--- a/program/src/free.rs
+++ b/program/src/free.rs
@@ -0,0 +1,31 @@
+use ore_api::prelude::*;
+use steel::*;
+
+/// Free up capacity.
+pub fn process_free(accounts: &[AccountInfo<'_>], _data: &[u8]) -> ProgramResult {
+    // Load accounts.
+    let clock = Clock::get()?;
+    let [signer_info, miner_info, receipt_info] = accounts else {
+        return Err(ProgramError::NotEnoughAccountKeys);
+    };
+    signer_info.is_signer()?;
+    let miner = miner_info
+        .as_account_mut::<Miner>(&ore_api::ID)?
+        .assert_mut(|m| m.authority == *signer_info.key)?;
+    let receipt = receipt_info
+        .as_account_mut::<Receipt>(&ore_api::ID)?
+        .assert_mut(|r| r.authority == *signer_info.key)?;
+
+    // Asset that block has ended.
+    let start_slot = 1500 * receipt.block_id;
+    let end_slot = start_slot + 1500;
+    assert!(clock.slot >= end_slot, "Block has not yet closed.");
+
+    // Free up miner capacity.
+    miner.deployed -= receipt.amount;
+
+    // Close the receipt.
+    receipt_info.close(signer_info)?;
+
+    Ok(())
+}
diff --git a/program/src/lib.rs b/program/src/lib.rs
index 886bc7d..fe2d02c 100644
--- a/program/src/lib.rs
+++ b/program/src/lib.rs
@@ -27,10 +27,19 @@ pub fn process_instruction(
     let (ix, data) = parse_instruction(&ore_api::ID, program_id, data)?;
 
     match ix {
+        // Mine
         OreInstruction::Open => process_open(accounts, data)?,
+        OreInstruction::Close => process_close(accounts, data)?,
         OreInstruction::Mine => process_mine(accounts, data)?,
 
-        _ => panic!("Not implemented"),
+        // Stake
+        OreInstruction::Deposit => process_deposit(accounts, data)?,
+        OreInstruction::Withdraw => process_withdraw(accounts, data)?,
+        OreInstruction::Free => process_free(accounts, data)?,
+
+        // Trade
+        OreInstruction::Buy => process_buy(accounts, data)?,
+        OreInstruction::Sell => process_sell(accounts, data)?,
     }
 
     Ok(())
diff --git a/program/src/mine.rs b/program/src/mine.rs
index 1c3ddaa..db5863f 100644
--- a/program/src/mine.rs
+++ b/program/src/mine.rs
@@ -2,7 +2,7 @@ use ore_api::prelude::*;
 use solana_program::keccak;
 use steel::*;
 
-/// Opens a new block for hashpower trading.
+/// Mine a block.
 pub fn process_mine(accounts: &[AccountInfo<'_>], data: &[u8]) -> ProgramResult {
     // Parse data.
     let args = Mine::try_from_bytes(data)?;
diff --git a/program/src/open.rs b/program/src/open.rs
index 75c70e7..315b8b4 100644
--- a/program/src/open.rs
+++ b/program/src/open.rs
@@ -1,14 +1,15 @@
 use ore_api::prelude::*;
+use solana_program::program_pack::Pack;
 use steel::*;
 
-/// Opens a new block for hashpower trading.
+/// Opens a new block.
 pub fn process_open(accounts: &[AccountInfo<'_>], data: &[u8]) -> ProgramResult {
     // Parse data.
     let args = Open::try_from_bytes(data)?;
     let id = u64::from_le_bytes(args.id);
 
     // Load accounts.
-    let [signer_info, block_info, system_program, token_program, associated_token_program] =
+    let [signer_info, block_info, market_info, market_hash_info, market_ore_info, mint_hash_info, mint_ore_info, system_program, token_program, associated_token_program, rent_sysvar] =
         accounts
     else {
         return Err(ProgramError::NotEnoughAccountKeys);
@@ -18,9 +19,19 @@ pub fn process_open(accounts: &[AccountInfo<'_>], data: &[u8]) -> ProgramResult
         .is_empty()?
         .is_writable()?
         .has_seeds(&[BLOCK, &id.to_le_bytes()], &ore_api::ID)?;
+    market_info
+        .is_empty()?
+        .is_writable()?
+        .has_seeds(&[MARKET, &id.to_le_bytes()], &ore_api::ID)?;
+    mint_hash_info
+        .is_empty()?
+        .is_writable()?
+        .has_seeds(&[MINT, &id.to_le_bytes()], &ore_api::ID)?;
+    mint_ore_info.has_address(&MINT_ADDRESS)?.as_mint()?;
     system_program.is_program(&system_program::ID)?;
     token_program.is_program(&spl_token::ID)?;
     associated_token_program.is_program(&spl_associated_token_account::ID)?;
+    rent_sysvar.is_sysvar(&sysvar::rent::ID)?;
 
     // Initialize config.
     create_program_account::<Block>(
@@ -38,30 +49,85 @@ pub fn process_open(accounts: &[AccountInfo<'_>], data: &[u8]) -> ProgramResult
     block.slot_hash = [0; 32];
     block.start_slot = 1500 * id;
 
-    // TODO Init market
-    // TODO Init hash token mint
-    // TODO Init token accounts for market
-    // TODO Init mint hash tokens to market
+    // Initialize market.
+    create_program_account::<Market>(
+        market_info,
+        system_program,
+        signer_info,
+        &ore_api::ID,
+        &[MARKET, &id.to_le_bytes()],
+    )?;
+    let market = market_info.as_account_mut::<Market>(&ore_api::ID)?;
+    market.id = id;
 
-    // // Initialize block token accounts.
-    // create_associated_token_account(
-    //     signer_info,
-    //     block_info,
-    //     block_commits_info,
-    //     sol_mint_info,
-    //     system_program,
-    //     token_program,
-    //     associated_token_program,
-    // )?;
-    // create_associated_token_account(
-    //     signer_info,
-    //     block_info,
-    //     block_ore_info,
-    //     ore_mint_info,
-    //     system_program,
-    //     token_program,
-    //     associated_token_program,
-    // )?;
+    // Initialize hash token mint.
+    allocate_account(
+        mint_hash_info,
+        system_program,
+        signer_info,
+        spl_token::state::Mint::LEN,
+        &spl_token::ID,
+        &[MINT, &id.to_le_bytes()],
+    )?;
+    initialize_mint_signed(
+        mint_hash_info,
+        block_info,
+        None,
+        token_program,
+        rent_sysvar,
+        0,
+        &[MINT, &id.to_le_bytes()],
+    )?;
+
+    // TODO Initialize hash token metadata.
+
+    // Initialize token accounts for market.
+    if market_hash_info.data_is_empty() {
+        create_associated_token_account(
+            signer_info,
+            market_info,
+            market_hash_info,
+            mint_hash_info,
+            system_program,
+            token_program,
+            associated_token_program,
+        )?;
+    } else {
+        market_hash_info.as_associated_token_account(market_info.key, mint_hash_info.key)?;
+    }
+    if market_ore_info.data_is_empty() {
+        create_associated_token_account(
+            signer_info,
+            market_info,
+            market_ore_info,
+            mint_ore_info,
+            system_program,
+            token_program,
+            associated_token_program,
+        )?;
+    } else {
+        market_ore_info.as_associated_token_account(market_info.key, mint_ore_info.key)?;
+    }
+
+    // Mint hash tokens to market.
+    mint_to_signed(
+        mint_hash_info,
+        market_hash_info,
+        block_info,
+        token_program,
+        10_000_000,
+        &[BLOCK, &id.to_le_bytes()],
+    )?;
+
+    // Burn mint authority.
+    set_authority_signed(
+        mint_hash_info,
+        block_info,
+        None,
+        spl_token_2022::instruction::AuthorityType::MintTokens,
+        token_program,
+        &[BLOCK, &id.to_le_bytes()],
+    )?;
 
     Ok(())
 }
diff --git a/program/src/sell.rs b/program/src/sell.rs
index e69de29..ca10b9a 100644
--- a/program/src/sell.rs
+++ b/program/src/sell.rs
@@ -0,0 +1,23 @@
+use ore_api::prelude::*;
+use steel::*;
+
+/// Sell hashpower.
+pub fn process_sell(accounts: &[AccountInfo<'_>], _data: &[u8]) -> ProgramResult {
+    // Load accounts.
+    let clock = Clock::get()?;
+    let [signer_info, block_info, market_info, miner_info, recipient_info, system_program, token_program] =
+        accounts
+    else {
+        return Err(ProgramError::NotEnoughAccountKeys);
+    };
+    signer_info.is_signer()?;
+    let block = block_info
+        .as_account_mut::<Block>(&ore_api::ID)?
+        .assert_mut(|b| clock.slot >= b.start_slot + 1500)?;
+    system_program.is_program(&system_program::ID)?;
+    token_program.is_program(&spl_token::ID)?;
+
+    // TODO Buy hash tokens
+
+    Ok(())
+}
diff --git a/program/src/withdraw.rs b/program/src/withdraw.rs
index e69de29..d4215f0 100644
--- a/program/src/withdraw.rs
+++ b/program/src/withdraw.rs
@@ -0,0 +1,46 @@
+use ore_api::prelude::*;
+use steel::*;
+
+/// Withdraws stake.
+pub fn process_withdraw(accounts: &[AccountInfo<'_>], data: &[u8]) -> ProgramResult {
+    // Parse data.
+    let args = Withdraw::try_from_bytes(data)?;
+    let amount = u64::from_le_bytes(args.amount);
+
+    // Load accounts.
+    let [signer_info, miner_info, recipient_info, treasury_info, treasury_tokens_info, token_program] =
+        accounts
+    else {
+        return Err(ProgramError::NotEnoughAccountKeys);
+    };
+    signer_info.is_signer()?;
+    let miner = miner_info
+        .as_account_mut::<Miner>(&ore_api::ID)?
+        .assert_mut(|m| m.authority == *signer_info.key)?;
+    recipient_info.as_associated_token_account(&signer_info.key, &MINT_ADDRESS)?;
+    let treasury = treasury_info.as_account_mut::<Treasury>(&ore_api::ID)?;
+    treasury_tokens_info.as_associated_token_account(&treasury_info.key, &MINT_ADDRESS)?;
+    token_program.is_program(&spl_token::ID)?;
+
+    // Update account state.
+    miner.stake -= amount;
+    treasury.total_stake -= amount;
+
+    // Asset miner has enough stake to cover the withdrawal.
+    assert!(
+        miner.stake >= miner.deployed,
+        "Withdrawal cannot reduce capacity below deployment levels."
+    );
+
+    // Execute transfer.
+    transfer_signed(
+        signer_info,
+        treasury_tokens_info,
+        recipient_info,
+        token_program,
+        amount,
+        &[TREASURY],
+    )?;
+
+    Ok(())
+}