Tokens pallet (#243)

* Use Monero-compatible additional TX keys This still sends a fingerprinting flare up if you send to a subaddress which needs to be fixed. Despite that, Monero no should no longer fail to scan TXs from monero-serai regarding additional keys. Previously it failed becuase we supplied one key as THE key, and n-1 as additional. Monero expects n for additional. This does correctly select when to use THE key versus when to use the additional key when sending. That removes the ability for recipients to fingerprint monero-serai by receiving to a standard address yet needing to use an additional key. * Add tokens_primitives Moves OutInstruction from in-instructions. Turns Destination into OutInstruction. * Correct in-instructions DispatchClass * Add initial tokens pallet * Don't allow pallet addresses to equal identity * Add support for InInstruction::transfer Requires a cargo update due to modifications made to serai-dex/substrate. Successfully mints a token to a SeraiAddress. * Bind InInstructions to an amount * Add a call filter to the runtime Prevents worrying about calls to the assets pallet/generally tightens things up. * Restore Destination It was meged into OutInstruction, yet it didn't make sense for OutInstruction to contain a SeraiAddress. Also deletes the excessively dated Scenarios doc. * Split PublicKey/SeraiAddress Lets us define a custom Display/ToString for SeraiAddress. Also resolves an oddity where PublicKey would be encoded as String, not [u8; 32]. * Test burning tokens/retrieving OutInstructions Modularizes processor_coinUpdates into a shared testing utility. * Misc lint * Don't use PolkadotExtrinsicParams
2024-12-22 19:49:22 +00:00 · 2023-01-28 01:47:13 -05:00 · 2023-01-28 01:47:13 -05:00 · 2ace339975
commit 2ace339975
parent f12cc2cca6
39 changed files with 1213 additions and 594 deletions
--- a/Cargo.lock
+++ b/Cargo.lock
--- a/Cargo.toml
+++ b/Cargo.toml
@ -25,6 +25,9 @@ members = [
  "substrate/serai/primitives",
  "substrate/serai/client",

+  "substrate/tokens/primitives",
+  "substrate/tokens/pallet",
+
  "substrate/in-instructions/primitives",
  "substrate/in-instructions/pallet",
  "substrate/in-instructions/client",
--- a/deny.toml
+++ b/deny.toml
@ -48,6 +48,8 @@ exceptions = [

  { allow = ["AGPL-3.0"], name = "serai-processor" },

+  { allow = ["AGPL-3.0"], name = "tokens-pallet" },
+
  { allow = ["AGPL-3.0"], name = "in-instructions-pallet" },
  { allow = ["AGPL-3.0"], name = "in-instructions-client" },

--- a/docs/integrations/Instructions.md
+++ b/docs/integrations/Instructions.md
@ -40,10 +40,10 @@ Serai token. If an Application Call, the encoded call will be executed.

 ### Refundable In Instruction

-  - `origin` (Option\<ExternalAddress>): Address, from the network of origin,
-which sent coins in.
-  - `instruction` (InInstruction):       The action to perform with the incoming
-coins.
+  - `origin`      (Option\<ExternalAddress>): Address, from the network of
+origin, which sent coins in.
+  - `instruction` (InInstruction):            The action to perform with the
+incoming coins.

 Networks may automatically provide `origin`. If they do, the instruction may
 still provide `origin`, overriding the automatically provided value.
@ -51,19 +51,18 @@ still provide `origin`, overriding the automatically provided value.
 If the instruction fails, coins are scheduled to be returned to `origin`,
 if provided.

-### Destination
-
-Destination is an enum of SeraiAddress and ExternalAddress.
-
 ### Out Instruction

-  - `destination` (Destination):   Address to receive coins to.
-  - `data`        (Option\<Data>): The data to call the destination with.
+  - `address` (ExternalAddress): Address to transfer the coins included with
+this instruction to.
+  - `data`    (Option<Data>):    Data to include when transferring coins.

-Transfer the coins included with this instruction to the specified address with
-the specified data. No validation of external addresses/data is performed
-on-chain. If data is specified for a chain not supporting data, it is silently
-dropped.
+No validation of external addresses/data is performed on-chain. If data is
+specified for a chain not supporting data, it is silently dropped.
+
+### Destination
+
+Destination is an enum of SeraiAddress and OutInstruction.

 ### Shorthand

@ -80,7 +79,7 @@ covered by Shorthand.
  - `origin`  (Option\<ExternalAddress>): Refundable In Instruction's `origin`.
  - `coin`    (Coin):                     Coin to swap funds for.
  - `minimum` (Amount):                   Minimum amount of `coin` to receive.
-  - `out`     (Out Instruction):          Final destination for funds.
+  - `out`     (Destination):              Final destination for funds.

 which expands to:

--- a/docs/integrations/Scenarios.md
+++ b/docs/integrations/Scenarios.md
@ -1,98 +0,0 @@
-# Scenarios
-
-### Pong
-
-Pong has Serai receive funds, just to return them. It's a demonstration of the
-in/out flow.
-
-```
-Shorthand::Raw(
-  In Instruction {
-    target: Incoming Asset Contract,
-    data:   native_transfer(Incoming Asset Sender)
-  }
-)
-```
-
-### Wrap
-
-Wrap wraps an asset from a connected chain into a Serai Asset, making it usable
-with applications on Serai, such as Serai DEX.
-
-```
-Shorthand::Raw(
-  In Instruction {
-    target: Serai Address
-  }
-)
-```
-
-### Swap SRI to Bitcoin
-
-For a SRI to Bitcoin swap, a SRI holder would perform an
-[Application Call](../Serai.md#application-calls) to Serai DEX, purchasing
-seraiBTC. Once they have seraiBTC, they are able to call `native_transfer`,
-transferring the BTC underlying the seraiBTC to a specified Bitcoin address.
-
-### Swap Bitcoin to Monero
-
-For a Bitcoin to Monero swap, the following Shorthand would be used.
-
-```
-Shorthand::Swap {
-  coin:    Monero,
-  minimum: Minimum Monero from Swap,
-  out:     Monero Address
-}
-```
-
- This Shorthand is expected to generally take:
-
-  - 1 byte to identify as Swap.
-  - 1 byte to not override `origin`.
-  - 1 byte for `coin`.
-  - 4 bytes for `minimum`.
-  - 1 byte for `out`'s `destination`'s ordinal byte.
-  - 65 bytes for `out`'s `destination`'s address.
-  - 1 byte to not include `data` in `out`.
-
-Or 74 bytes.
-
-### Add Liquidity (Fresh)
-
-For a user who has never used Serai before, they have three requirements to add
-liquidity:
-
-  - Minting the Serai asset they wish to add liquidity for
-  - Acquiring Serai, as liquidity is symmetric
-  - Acquiring Serai for gas fees
-
-The Add Liquidity Shorthand enables all three of these actions, and actually
-adding the liquidity, in just one transaction from a connected network.
-
-```
-Shorthand::AddLiquidity {
-  minimum: Minimum SRI from Swap,
-  gas:     Amount of SRI to keep for gas
-  address: Serai address for the liquidity tokens and gas
-}
-```
-
-For adding liquidity from Bitcoin, this Shorthand is expected to generally take:
-
-  - 1 byte to identify as Add Liquidity.
-  - 1 byte to not override `origin`.
-  - 5 bytes for `minimum`.
-  - 4 bytes for `gas`.
-  - 32 bytes for `address`.
-
-Or 43 bytes.
-
-### Add Liquidity (SRI Holder)
-
-For a user who already has SRI, they solely need to have the asset they wish to
-add liquidity for via their SRI. They can either purchase it from Serai DEX, or
-wrap it as detailed above.
-
-Once they have both their SRI and the asset they wish to provide liquidity for,
-they would use a Serai transaction to call the DEX, adding the liquidity.
--- a/substrate/in-instructions/pallet/Cargo.toml
+++ b/substrate/in-instructions/pallet/Cargo.toml
@ -29,6 +29,8 @@ frame-support = { git = "https://github.com/serai-dex/substrate", default-featur
 serai-primitives = { path = "../../serai/primitives", default-features = false }
 in-instructions-primitives = { path = "../primitives", default-features = false }

+tokens-pallet = { path = "../../tokens/pallet", default-features = false }
+
 [features]
 std = [
  "thiserror",
@ -47,5 +49,7 @@ std = [

  "serai-primitives/std",
  "in-instructions-primitives/std",
+
+  "tokens-pallet/std",
 ]
 default = ["std"]
--- a/substrate/in-instructions/pallet/src/lib.rs
+++ b/substrate/in-instructions/pallet/src/lib.rs
@ -13,7 +13,7 @@ use sp_inherents::{InherentIdentifier, IsFatalError};

 use sp_runtime::RuntimeDebug;

-use serai_primitives::{BlockNumber, BlockHash, Coin};
+use serai_primitives::{BlockNumber, BlockHash, Coin, WithAmount, Balance};

 pub use in_instructions_primitives as primitives;
 use primitives::InInstruction;
@ -24,7 +24,7 @@ pub const INHERENT_IDENTIFIER: InherentIdentifier = *b"ininstrs";
 #[cfg_attr(feature = "std", derive(Serialize, Deserialize))]
 pub struct Batch {
  pub id: BlockHash,
-  pub instructions: Vec<InInstruction>,
+  pub instructions: Vec<WithAmount<InInstruction>>,
 }

 #[derive(Clone, PartialEq, Eq, Encode, Decode, TypeInfo, RuntimeDebug)]
@ -89,10 +89,12 @@ pub mod pallet {
  use frame_support::pallet_prelude::*;
  use frame_system::pallet_prelude::*;

+  use tokens_pallet::{Config as TokensConfig, Pallet as Tokens};
+
  use super::*;

  #[pallet::config]
-  pub trait Config: frame_system::Config<BlockNumber = u32> {
+  pub trait Config: frame_system::Config<BlockNumber = u32> + TokensConfig {
    type RuntimeEvent: From<Event<Self>> + IsType<<Self as frame_system::Config>::RuntimeEvent>;
  }

@ -100,6 +102,7 @@ pub mod pallet {
  #[pallet::generate_deposit(fn deposit_event)]
  pub enum Event<T: Config> {
    Batch { coin: Coin, id: BlockHash },
+    Failure { coin: Coin, id: BlockHash, index: u32 },
  }

  #[pallet::pallet]
@ -122,23 +125,43 @@ pub mod pallet {
    }
  }

+  impl<T: Config> Pallet<T> {
+    fn execute(coin: Coin, instruction: WithAmount<InInstruction>) -> Result<(), ()> {
+      match instruction.data {
+        InInstruction::Transfer(address) => {
+          Tokens::<T>::mint(address, Balance { coin, amount: instruction.amount })
+        }
+        _ => panic!("unsupported instruction"),
+      }
+      Ok(())
+    }
+  }
+
  #[pallet::call]
  impl<T: Config> Pallet<T> {
    #[pallet::call_index(0)]
-    #[pallet::weight((0, DispatchClass::Mandatory))] // TODO
-    pub fn execute(origin: OriginFor<T>, updates: Updates) -> DispatchResult {
+    #[pallet::weight((0, DispatchClass::Operational))] // TODO
+    pub fn update(origin: OriginFor<T>, mut updates: Updates) -> DispatchResult {
      ensure_none(origin)?;
      assert!(!Once::<T>::exists());
      Once::<T>::put(true);

-      for (coin, update) in updates.iter().enumerate() {
+      for (coin, update) in updates.iter_mut().enumerate() {
        if let Some(update) = update {
          let coin = coin_from_index(coin);
          BlockNumbers::<T>::insert(coin, update.block_number);

-          for batch in &update.batches {
-            // TODO: EXECUTE
+          for batch in update.batches.iter_mut() {
            Self::deposit_event(Event::Batch { coin, id: batch.id });
+            for (i, instruction) in batch.instructions.drain(..).enumerate() {
+              if Self::execute(coin, instruction).is_err() {
+                Self::deposit_event(Event::Failure {
+                  coin,
+                  id: batch.id,
+                  index: u32::try_from(i).unwrap(),
+                });
+              }
+            }
          }
        }
      }
@ -157,7 +180,7 @@ pub mod pallet {
      data
        .get_data::<Updates>(&INHERENT_IDENTIFIER)
        .unwrap()
-        .map(|updates| Call::execute { updates })
+        .map(|updates| Call::update { updates })
    }

    // Assumes that only not yet handled batches are provided as inherent data
@ -167,7 +190,7 @@ pub mod pallet {
      let expected = data.get_data::<Updates>(&INHERENT_IDENTIFIER).unwrap().unwrap();
      // Match to be exhaustive
      let updates = match call {
-        Call::execute { ref updates } => updates,
+        Call::update { ref updates } => updates,
        _ => Err(InherentError::InvalidCall)?,
      };

--- a/substrate/in-instructions/primitives/Cargo.toml
+++ b/substrate/in-instructions/primitives/Cargo.toml
@ -16,10 +16,9 @@ scale-info = { version = "2", default-features = false, features = ["derive"] }

 serde = { version = "1", features = ["derive"], optional = true }

-sp-core = { git = "https://github.com/serai-dex/substrate", default-features = false }
-
 serai-primitives = { path = "../../serai/primitives", default-features = false }
+tokens-primitives = { path = "../../tokens/primitives", default-features = false }

 [features]
-std = ["scale/std", "scale-info/std", "serde", "sp-core/std", "serai-primitives/std"]
+std = ["scale/std", "scale-info/std", "serde", "serai-primitives/std", "tokens-primitives/std"]
 default = ["std"]
--- a/substrate/in-instructions/primitives/src/incoming.rs
+++ b/substrate/in-instructions/primitives/src/incoming.rs
@ -1,38 +0,0 @@
-use scale::{Encode, Decode, MaxEncodedLen};
-use scale_info::TypeInfo;
-
-#[cfg(feature = "std")]
-use serde::{Serialize, Deserialize};
-
-use sp_core::{ConstU32, bounded::BoundedVec};
-
-use serai_primitives::SeraiAddress;
-
-use crate::{MAX_DATA_LEN, ExternalAddress};
-
-#[derive(Clone, Copy, PartialEq, Eq, Debug, Encode, Decode, MaxEncodedLen, TypeInfo)]
-#[cfg_attr(feature = "std", derive(Serialize, Deserialize))]
-pub enum Application {
-  DEX,
-}
-
-#[derive(Clone, PartialEq, Eq, Debug, Encode, Decode, MaxEncodedLen, TypeInfo)]
-#[cfg_attr(feature = "std", derive(Serialize, Deserialize))]
-pub struct ApplicationCall {
-  application: Application,
-  data: BoundedVec<u8, ConstU32<{ MAX_DATA_LEN }>>,
-}
-
-#[derive(Clone, PartialEq, Eq, Debug, Encode, Decode, MaxEncodedLen, TypeInfo)]
-#[cfg_attr(feature = "std", derive(Serialize, Deserialize))]
-pub enum InInstruction {
-  Transfer(SeraiAddress),
-  Call(ApplicationCall),
-}
-
-#[derive(Clone, PartialEq, Eq, Debug, Encode, Decode, MaxEncodedLen, TypeInfo)]
-#[cfg_attr(feature = "std", derive(Serialize, Deserialize))]
-pub struct RefundableInInstruction {
-  pub origin: Option<ExternalAddress>,
-  pub instruction: InInstruction,
-}
--- a/substrate/in-instructions/primitives/src/lib.rs
+++ b/substrate/in-instructions/primitives/src/lib.rs
@ -8,40 +8,34 @@ use scale_info::TypeInfo;
 #[cfg(feature = "std")]
 use serde::{Serialize, Deserialize};

-use sp_core::{ConstU32, bounded::BoundedVec};
-
-// Monero, our current longest address candidate, has a longest address of featured with payment ID
-// 1 (enum) + 1 (flags) + 64 (two keys) + 8 (payment ID) = 74
-pub const MAX_ADDRESS_LEN: u32 = 74;
-// Should be enough for a Uniswap v3 call
-pub const MAX_DATA_LEN: u32 = 512;
-
-#[derive(Clone, PartialEq, Eq, Debug, Encode, Decode, MaxEncodedLen, TypeInfo)]
-#[cfg_attr(feature = "std", derive(Serialize, Deserialize))]
-pub struct ExternalAddress(BoundedVec<u8, ConstU32<{ MAX_ADDRESS_LEN }>>);
-impl ExternalAddress {
-  #[cfg(feature = "std")]
-  pub fn new(address: Vec<u8>) -> Result<ExternalAddress, &'static str> {
-    Ok(ExternalAddress(address.try_into().map_err(|_| "address length exceeds {MAX_ADDRESS_LEN}")?))
-  }
-
-  pub fn address(&self) -> &[u8] {
-    self.0.as_ref()
-  }
-
-  #[cfg(feature = "std")]
-  pub fn consume(self) -> Vec<u8> {
-    self.0.into_inner()
-  }
-}
-
-// Not "in" as "in" is a keyword
-mod incoming;
-pub use incoming::*;
-
-// Not "out" to match in
-mod outgoing;
-pub use outgoing::*;
+use serai_primitives::{SeraiAddress, ExternalAddress, Data};

 mod shorthand;
 pub use shorthand::*;
+
+#[derive(Clone, Copy, PartialEq, Eq, Debug, Encode, Decode, MaxEncodedLen, TypeInfo)]
+#[cfg_attr(feature = "std", derive(Serialize, Deserialize))]
+pub enum Application {
+  DEX,
+}
+
+#[derive(Clone, PartialEq, Eq, Debug, Encode, Decode, MaxEncodedLen, TypeInfo)]
+#[cfg_attr(feature = "std", derive(Serialize, Deserialize))]
+pub struct ApplicationCall {
+  application: Application,
+  data: Data,
+}
+
+#[derive(Clone, PartialEq, Eq, Debug, Encode, Decode, MaxEncodedLen, TypeInfo)]
+#[cfg_attr(feature = "std", derive(Serialize, Deserialize))]
+pub enum InInstruction {
+  Transfer(SeraiAddress),
+  Call(ApplicationCall),
+}
+
+#[derive(Clone, PartialEq, Eq, Debug, Encode, Decode, MaxEncodedLen, TypeInfo)]
+#[cfg_attr(feature = "std", derive(Serialize, Deserialize))]
+pub struct RefundableInInstruction {
+  pub origin: Option<ExternalAddress>,
+  pub instruction: InInstruction,
+}
--- a/substrate/in-instructions/primitives/src/outgoing.rs
+++ b/substrate/in-instructions/primitives/src/outgoing.rs
@ -1,25 +0,0 @@
-use scale::{Encode, Decode, MaxEncodedLen};
-use scale_info::TypeInfo;
-
-#[cfg(feature = "std")]
-use serde::{Serialize, Deserialize};
-
-use sp_core::{ConstU32, bounded::BoundedVec};
-
-use serai_primitives::SeraiAddress;
-
-use crate::{MAX_DATA_LEN, ExternalAddress};
-
-#[derive(Clone, PartialEq, Eq, Debug, Encode, Decode, MaxEncodedLen, TypeInfo)]
-#[cfg_attr(feature = "std", derive(Serialize, Deserialize))]
-pub enum Destination {
-  Native(SeraiAddress),
-  External(ExternalAddress),
-}
-
-#[derive(Clone, PartialEq, Eq, Debug, Encode, Decode, MaxEncodedLen, TypeInfo)]
-#[cfg_attr(feature = "std", derive(Serialize, Deserialize))]
-pub struct OutInstruction {
-  destination: Destination,
-  data: Option<BoundedVec<u8, ConstU32<{ MAX_DATA_LEN }>>>,
-}
--- a/substrate/in-instructions/primitives/src/shorthand.rs
+++ b/substrate/in-instructions/primitives/src/shorthand.rs
@ -4,16 +4,18 @@ use scale_info::TypeInfo;
 #[cfg(feature = "std")]
 use serde::{Serialize, Deserialize};

-use sp_core::{ConstU32, bounded::BoundedVec};
+use serai_primitives::{Coin, Amount, SeraiAddress, ExternalAddress, Data};

-use serai_primitives::{SeraiAddress, Coin, Amount};
+use tokens_primitives::OutInstruction;

-use crate::{MAX_DATA_LEN, ExternalAddress, RefundableInInstruction, InInstruction, OutInstruction};
+use crate::RefundableInInstruction;
+#[cfg(feature = "std")]
+use crate::InInstruction;

 #[derive(Clone, PartialEq, Eq, Debug, Encode, Decode, MaxEncodedLen, TypeInfo)]
 #[cfg_attr(feature = "std", derive(Serialize, Deserialize))]
 pub enum Shorthand {
-  Raw(BoundedVec<u8, ConstU32<{ MAX_DATA_LEN }>>),
+  Raw(Data),
  Swap {
    origin: Option<ExternalAddress>,
    coin: Coin,
@ -29,9 +31,10 @@ pub enum Shorthand {
 }

 impl Shorthand {
+  #[cfg(feature = "std")]
  pub fn transfer(origin: Option<ExternalAddress>, address: SeraiAddress) -> Option<Self> {
    Some(Self::Raw(
-      BoundedVec::try_from(
+      Data::new(
        (RefundableInInstruction { origin, instruction: InInstruction::Transfer(address) })
          .encode(),
      )
@ -45,7 +48,7 @@ impl TryFrom<Shorthand> for RefundableInInstruction {
  fn try_from(shorthand: Shorthand) -> Result<RefundableInInstruction, &'static str> {
    Ok(match shorthand {
      Shorthand::Raw(raw) => {
-        RefundableInInstruction::decode(&mut raw.as_ref()).map_err(|_| "invalid raw instruction")?
+        RefundableInInstruction::decode(&mut raw.data()).map_err(|_| "invalid raw instruction")?
      }
      Shorthand::Swap { .. } => todo!(),
      Shorthand::AddLiquidity { .. } => todo!(),
--- a/substrate/node/src/chain_spec.rs
+++ b/substrate/node/src/chain_spec.rs
@ -1,43 +1,42 @@
-use sp_core::{Decode, Pair as PairTrait, sr25519::Pair};
-use sp_runtime::traits::TrailingZeroInput;
+use sp_core::Pair as PairTrait;

 use sc_service::ChainType;

 use serai_runtime::{
-  primitives::*, tendermint::crypto::Public, WASM_BINARY, opaque::SessionKeys, GenesisConfig,
-  SystemConfig, BalancesConfig, AssetsConfig, ValidatorSetsConfig, SessionConfig,
+  primitives::*, tokens::primitives::ADDRESS as TOKENS_ADDRESS, tendermint::crypto::Public,
+  WASM_BINARY, opaque::SessionKeys, GenesisConfig, SystemConfig, BalancesConfig, AssetsConfig,
+  ValidatorSetsConfig, SessionConfig,
 };

 pub type ChainSpec = sc_service::GenericChainSpec<GenesisConfig>;

-fn insecure_pair_from_name(name: &'static str) -> Pair {
-  Pair::from_string(&format!("//{name}"), None).unwrap()
-}
-
-fn address_from_name(name: &'static str) -> SeraiAddress {
+fn account_from_name(name: &'static str) -> PublicKey {
  insecure_pair_from_name(name).public()
 }

 fn testnet_genesis(
  wasm_binary: &[u8],
  validators: &[&'static str],
-  endowed_accounts: Vec<SeraiAddress>,
+  endowed_accounts: Vec<PublicKey>,
 ) -> GenesisConfig {
  let session_key = |name| {
-    let key = address_from_name(name);
+    let key = account_from_name(name);
    (key, key, SessionKeys { tendermint: Public::from(key) })
  };

-  // TODO: Replace with a call to the pallet to ask for its account
-  let owner = SeraiAddress::decode(&mut TrailingZeroInput::new(b"tokens")).unwrap();
-
  GenesisConfig {
    system: SystemConfig { code: wasm_binary.to_vec() },
+
    balances: BalancesConfig {
      balances: endowed_accounts.iter().cloned().map(|k| (k, 1 << 60)).collect(),
    },
+    transaction_payment: Default::default(),
+
    assets: AssetsConfig {
-      assets: [BITCOIN, ETHER, DAI, MONERO].iter().map(|coin| (*coin, owner, true, 1)).collect(),
+      assets: [BITCOIN, ETHER, DAI, MONERO]
+        .iter()
+        .map(|coin| (*coin, TOKENS_ADDRESS.into(), true, 1))
+        .collect(),
      metadata: vec![
        (BITCOIN, b"Bitcoin".to_vec(), b"BTC".to_vec(), 8),
        // Reduce to 8 decimals to feasibly fit within u64 (instead of its native u256)
@ -47,14 +46,13 @@ fn testnet_genesis(
      ],
      accounts: vec![],
    },
-    transaction_payment: Default::default(),

-    validator_sets: ValidatorSetsConfig {
-      bond: Amount(1_000_000) * COIN,
-      coins: vec![BITCOIN, ETHER, DAI, MONERO],
-      participants: validators.iter().map(|name| address_from_name(name)).collect(),
-    },
    session: SessionConfig { keys: validators.iter().map(|name| session_key(*name)).collect() },
+    validator_sets: ValidatorSetsConfig {
+      bond: Amount(1_000_000 * 10_u64.pow(8)),
+      coins: vec![BITCOIN, ETHER, DAI, MONERO],
+      participants: validators.iter().map(|name| account_from_name(name)).collect(),
+    },
  }
 }

@ -72,18 +70,18 @@ pub fn development_config() -> Result<ChainSpec, &'static str> {
        wasm_binary,
        &["Alice"],
        vec![
-          address_from_name("Alice"),
-          address_from_name("Bob"),
-          address_from_name("Charlie"),
-          address_from_name("Dave"),
-          address_from_name("Eve"),
-          address_from_name("Ferdie"),
-          address_from_name("Alice//stash"),
-          address_from_name("Bob//stash"),
-          address_from_name("Charlie//stash"),
-          address_from_name("Dave//stash"),
-          address_from_name("Eve//stash"),
-          address_from_name("Ferdie//stash"),
+          account_from_name("Alice"),
+          account_from_name("Bob"),
+          account_from_name("Charlie"),
+          account_from_name("Dave"),
+          account_from_name("Eve"),
+          account_from_name("Ferdie"),
+          account_from_name("Alice//stash"),
+          account_from_name("Bob//stash"),
+          account_from_name("Charlie//stash"),
+          account_from_name("Dave//stash"),
+          account_from_name("Eve//stash"),
+          account_from_name("Ferdie//stash"),
        ],
      )
    },
@ -116,18 +114,18 @@ pub fn testnet_config() -> Result<ChainSpec, &'static str> {
        wasm_binary,
        &["Alice", "Bob", "Charlie"],
        vec![
-          address_from_name("Alice"),
-          address_from_name("Bob"),
-          address_from_name("Charlie"),
-          address_from_name("Dave"),
-          address_from_name("Eve"),
-          address_from_name("Ferdie"),
-          address_from_name("Alice//stash"),
-          address_from_name("Bob//stash"),
-          address_from_name("Charlie//stash"),
-          address_from_name("Dave//stash"),
-          address_from_name("Eve//stash"),
-          address_from_name("Ferdie//stash"),
+          account_from_name("Alice"),
+          account_from_name("Bob"),
+          account_from_name("Charlie"),
+          account_from_name("Dave"),
+          account_from_name("Eve"),
+          account_from_name("Ferdie"),
+          account_from_name("Alice//stash"),
+          account_from_name("Bob//stash"),
+          account_from_name("Charlie//stash"),
+          account_from_name("Dave//stash"),
+          account_from_name("Eve//stash"),
+          account_from_name("Ferdie//stash"),
        ],
      )
    },
--- a/substrate/node/src/command_helper.rs
+++ b/substrate/node/src/command_helper.rs
@ -67,7 +67,7 @@ pub fn create_benchmark_extrinsic(

  UncheckedExtrinsic::new_signed(
    call.clone(),
-    sender.public(),
+    sender.public().into(),
    SignedPayload::from_raw(
      call,
      extra.clone(),
--- a/substrate/node/src/rpc.rs
+++ b/substrate/node/src/rpc.rs
@ -6,7 +6,11 @@ use sp_blockchain::{Error as BlockchainError, HeaderBackend, HeaderMetadata};
 use sp_block_builder::BlockBuilder;
 use sp_api::ProvideRuntimeApi;

-use serai_runtime::{primitives::SeraiAddress, opaque::Block, Balance, Index};
+use serai_runtime::{
+  primitives::{SubstrateAmount, PublicKey},
+  opaque::Block,
+  Index,
+};

 pub use sc_rpc_api::DenyUnsafe;
 use sc_transaction_pool_api::TransactionPool;
@ -29,8 +33,8 @@ pub fn create_full<
  deps: FullDeps<C, P>,
 ) -> Result<RpcModule<()>, Box<dyn std::error::Error + Send + Sync>>
 where
-  C::Api: substrate_frame_rpc_system::AccountNonceApi<Block, SeraiAddress, Index>
-    + pallet_transaction_payment_rpc::TransactionPaymentRuntimeApi<Block, Balance>
+  C::Api: substrate_frame_rpc_system::AccountNonceApi<Block, PublicKey, Index>
+    + pallet_transaction_payment_rpc::TransactionPaymentRuntimeApi<Block, SubstrateAmount>
    + BlockBuilder<Block>,
 {
  use substrate_frame_rpc_system::{System, SystemApiServer};
--- a/substrate/node/src/service.rs
+++ b/substrate/node/src/service.rs
@ -76,9 +76,9 @@ impl TendermintClientMinimal for TendermintValidatorFirm {
  // guaranteed not to grow the block?
  const PROPOSED_BLOCK_SIZE_LIMIT: usize = { BLOCK_SIZE as usize };
  // 3 seconds
-  const BLOCK_PROCESSING_TIME_IN_SECONDS: u32 = { (TARGET_BLOCK_TIME / 2 / 1000) as u32 };
+  const BLOCK_PROCESSING_TIME_IN_SECONDS: u32 = { (TARGET_BLOCK_TIME / 2) as u32 };
  // 1 second
-  const LATENCY_TIME_IN_SECONDS: u32 = { (TARGET_BLOCK_TIME / 2 / 3 / 1000) as u32 };
+  const LATENCY_TIME_IN_SECONDS: u32 = { (TARGET_BLOCK_TIME / 2 / 3) as u32 };

  type Block = Block;
  type Backend = sc_client_db::Backend<Block>;
@ -101,7 +101,7 @@ impl TendermintValidator for TendermintValidatorFirm {
 pub fn new_partial(
  config: &Configuration,
 ) -> Result<(TendermintImport<TendermintValidatorFirm>, PartialComponents), ServiceError> {
-  debug_assert_eq!(TARGET_BLOCK_TIME, 6000);
+  debug_assert_eq!(TARGET_BLOCK_TIME, 6);

  if config.keystore_remote.is_some() {
    return Err(ServiceError::Other("Remote Keystores are not supported".to_string()));
--- a/substrate/runtime/Cargo.toml
+++ b/substrate/runtime/Cargo.toml
@ -41,6 +41,7 @@ pallet-balances = { git = "https://github.com/serai-dex/substrate", default-feat
 pallet-assets = { git = "https://github.com/serai-dex/substrate", default-features = false }
 pallet-transaction-payment = { git = "https://github.com/serai-dex/substrate", default-features = false }

+tokens-pallet = { path = "../tokens/pallet", default-features = false }
 in-instructions-pallet = { path = "../in-instructions/pallet", default-features = false }

 validator-sets-pallet = { path = "../validator-sets/pallet", default-features = false }
@ -78,9 +79,10 @@ std = [
  "serai-primitives/std",

  "pallet-balances/std",
-  "pallet-assets/std",
  "pallet-transaction-payment/std",

+  "pallet-assets/std",
+  "tokens-pallet/std",
  "in-instructions-pallet/std",

  "validator-sets-pallet/std",
--- a/substrate/runtime/src/lib.rs
+++ b/substrate/runtime/src/lib.rs
@ -16,6 +16,7 @@ pub use pallet_balances as balances;
 pub use pallet_transaction_payment as transaction_payment;

 pub use pallet_assets as assets;
+pub use tokens_pallet as tokens;
 pub use in_instructions_pallet as in_instructions;

 pub use validator_sets_pallet as validator_sets;
@ -33,15 +34,15 @@ use sp_version::NativeVersion;

 use sp_runtime::{
  create_runtime_str, generic, impl_opaque_keys, KeyTypeId,
-  traits::{Convert, OpaqueKeys, IdentityLookup, BlakeTwo256, Block as BlockT},
+  traits::{Convert, OpaqueKeys, BlakeTwo256, Block as BlockT},
  transaction_validity::{TransactionSource, TransactionValidity},
  ApplyExtrinsicResult, Perbill,
 };

-use primitives::{PublicKey, Signature, SeraiAddress, Coin};
+use primitives::{PublicKey, SeraiAddress, AccountLookup, Signature, SubstrateAmount, Coin};

 use support::{
-  traits::{ConstU8, ConstU32, ConstU64},
+  traits::{ConstU8, ConstU32, ConstU64, Contains},
  weights::{
    constants::{RocksDbWeight, WEIGHT_REF_TIME_PER_SECOND},
    IdentityFee, Weight,
@ -56,14 +57,6 @@ use session::PeriodicSessions;
 /// An index to a block.
 pub type BlockNumber = u32;

-/// Balance of an account.
-// Distinct from serai-primitives Amount due to Substrate's requirements on this type.
-// If Amount could be dropped in here, it would be.
-// While Amount could have all the necessary traits implemented, not only are they many, yet it'd
-// make Amount a larger type, providing more operations than desired.
-// The current type's minimalism sets clear bounds on usage.
-pub type Balance = u64;
-
 /// Index of a transaction in the chain, for a given account.
 pub type Index = u32;

@ -104,10 +97,10 @@ pub const VERSION: RuntimeVersion = RuntimeVersion {
 // 1 MB
 pub const BLOCK_SIZE: u32 = 1024 * 1024;
 // 6 seconds
-pub const TARGET_BLOCK_TIME: u64 = 6000;
+pub const TARGET_BLOCK_TIME: u64 = 6;

 /// Measured in blocks.
-pub const MINUTES: BlockNumber = 60_000 / (TARGET_BLOCK_TIME as BlockNumber);
+pub const MINUTES: BlockNumber = 60 / (TARGET_BLOCK_TIME as BlockNumber);
 pub const HOURS: BlockNumber = MINUTES * 60;
 pub const DAYS: BlockNumber = HOURS * 24;

@ -134,13 +127,44 @@ parameter_types! {
    );
 }

+pub struct CallFilter;
+impl Contains<RuntimeCall> for CallFilter {
+  fn contains(call: &RuntimeCall) -> bool {
+    if let RuntimeCall::Balances(call) = call {
+      return matches!(call, balances::Call::transfer { .. } | balances::Call::transfer_all { .. });
+    }
+
+    if let RuntimeCall::Assets(call) = call {
+      return matches!(
+        call,
+        assets::Call::approve_transfer { .. } |
+          assets::Call::cancel_approval { .. } |
+          assets::Call::transfer { .. } |
+          assets::Call::transfer_approved { .. }
+      );
+    }
+    if let RuntimeCall::Tokens(call) = call {
+      return matches!(call, tokens::Call::burn { .. });
+    }
+    if let RuntimeCall::InInstructions(call) = call {
+      return matches!(call, in_instructions::Call::update { .. });
+    }
+
+    if let RuntimeCall::ValidatorSets(call) = call {
+      return matches!(call, validator_sets::Call::vote { .. });
+    }
+
+    false
+  }
+}
+
 impl system::Config for Runtime {
-  type BaseCallFilter = support::traits::Everything;
+  type BaseCallFilter = CallFilter;
  type BlockWeights = BlockWeights;
  type BlockLength = BlockLength;
-  type AccountId = SeraiAddress;
+  type AccountId = PublicKey;
  type RuntimeCall = RuntimeCall;
-  type Lookup = IdentityLookup<SeraiAddress>;
+  type Lookup = AccountLookup;
  type Index = Index;
  type BlockNumber = BlockNumber;
  type Hash = Hash;
@ -157,7 +181,7 @@ impl system::Config for Runtime {
  type OnKilledAccount = ();
  type OnSetCode = ();

-  type AccountData = balances::AccountData<Balance>;
+  type AccountData = balances::AccountData<SubstrateAmount>;
  type SystemWeightInfo = ();
  type SS58Prefix = SS58Prefix; // TODO: Remove for Bech32m

@ -168,7 +192,7 @@ impl balances::Config for Runtime {
  type MaxLocks = ConstU32<50>;
  type MaxReserves = ();
  type ReserveIdentifier = [u8; 8];
-  type Balance = Balance;
+  type Balance = SubstrateAmount;
  type RuntimeEvent = RuntimeEvent;
  type DustRemoval = ();
  type ExistentialDeposit = ConstU64<500>;
@ -176,9 +200,18 @@ impl balances::Config for Runtime {
  type WeightInfo = balances::weights::SubstrateWeight<Runtime>;
 }

+impl transaction_payment::Config for Runtime {
+  type RuntimeEvent = RuntimeEvent;
+  type OnChargeTransaction = CurrencyAdapter<Balances, ()>;
+  type OperationalFeeMultiplier = ConstU8<5>;
+  type WeightToFee = IdentityFee<SubstrateAmount>;
+  type LengthToFee = IdentityFee<SubstrateAmount>;
+  type FeeMultiplierUpdate = ();
+}
+
 impl assets::Config for Runtime {
  type RuntimeEvent = RuntimeEvent;
-  type Balance = Balance;
+  type Balance = SubstrateAmount;
  type Currency = Balances;

  type AssetId = Coin;
@ -186,8 +219,8 @@ impl assets::Config for Runtime {
  type StringLimit = ConstU32<32>;

  // Don't allow anyone to create assets
-  type CreateOrigin = support::traits::AsEnsureOriginWithArg<system::EnsureNever<SeraiAddress>>;
-  type ForceOrigin = system::EnsureRoot<SeraiAddress>;
+  type CreateOrigin = support::traits::AsEnsureOriginWithArg<system::EnsureNever<PublicKey>>;
+  type ForceOrigin = system::EnsureRoot<PublicKey>;

  // Don't charge fees nor kill accounts
  type RemoveItemsLimit = ConstU32<0>;
@ -207,13 +240,8 @@ impl assets::Config for Runtime {
  type BenchmarkHelper = ();
 }

-impl transaction_payment::Config for Runtime {
+impl tokens::Config for Runtime {
  type RuntimeEvent = RuntimeEvent;
-  type OnChargeTransaction = CurrencyAdapter<Balances, ()>;
-  type OperationalFeeMultiplier = ConstU8<5>;
-  type WeightToFee = IdentityFee<Balance>;
-  type LengthToFee = IdentityFee<Balance>;
-  type FeeMultiplierUpdate = ();
 }

 impl in_instructions::Config for Runtime {
@ -236,7 +264,7 @@ impl validator_sets::Config for Runtime {

 impl session::Config for Runtime {
  type RuntimeEvent = RuntimeEvent;
-  type ValidatorId = SeraiAddress;
+  type ValidatorId = PublicKey;
  type ValidatorIdOf = IdentityValidatorIdOf;
  type ShouldEndSession = Sessions;
  type NextSessionRotation = Sessions;
@ -283,6 +311,7 @@ construct_runtime!(
    TransactionPayment: transaction_payment,

    Assets: assets,
+    Tokens: tokens,
    InInstructions: in_instructions,

    ValidatorSets: validator_sets,
@ -381,31 +410,31 @@ sp_api::impl_runtime_apis! {
    }

    fn validators() -> Vec<PublicKey> {
-      Session::validators()
+      Session::validators().drain(..).map(Into::into).collect()
    }
  }

-  impl frame_system_rpc_runtime_api::AccountNonceApi<Block, SeraiAddress, Index> for Runtime {
-    fn account_nonce(account: SeraiAddress) -> Index {
+  impl frame_system_rpc_runtime_api::AccountNonceApi<Block, PublicKey, Index> for Runtime {
+    fn account_nonce(account: PublicKey) -> Index {
      System::account_nonce(account)
    }
  }

  impl pallet_transaction_payment_rpc_runtime_api::TransactionPaymentApi<
    Block,
-    Balance
+    SubstrateAmount
  > for Runtime {
    fn query_info(
      uxt: <Block as BlockT>::Extrinsic,
      len: u32,
-    ) -> pallet_transaction_payment_rpc_runtime_api::RuntimeDispatchInfo<Balance> {
+    ) -> pallet_transaction_payment_rpc_runtime_api::RuntimeDispatchInfo<SubstrateAmount> {
      TransactionPayment::query_info(uxt, len)
    }

    fn query_fee_details(
      uxt: <Block as BlockT>::Extrinsic,
      len: u32,
-    ) -> transaction_payment::FeeDetails<Balance> {
+    ) -> transaction_payment::FeeDetails<SubstrateAmount> {
      TransactionPayment::query_fee_details(uxt, len)
    }
  }
--- a/substrate/serai/client/Cargo.toml
+++ b/substrate/serai/client/Cargo.toml
@ -15,19 +15,22 @@ rustdoc-args = ["--cfg", "docsrs"]
 [dependencies]
 thiserror = "1"

-serde = { version = "1", features = ["derive"] }
-
 scale = { package = "parity-scale-codec", version = "3" }
+scale-info = "2"
 scale-value = "0.6"
-subxt = "0.25"
+
+sp-core = { git = "https://github.com/serai-dex/substrate", version = "7" }

 serai-primitives = { path = "../primitives", version = "0.1" }
-in-instructions-primitives = { path = "../../in-instructions/primitives", version = "0.1" }
 serai-runtime = { path = "../../runtime", version = "0.1" }

+subxt = "0.25"
+
 [dev-dependencies]
 lazy_static = "1"

+rand_core = "0.6"
+
 tokio = "1"

 jsonrpsee-server = "0.16"
--- a/substrate/serai/client/metadata.json
+++ b/substrate/serai/client/metadata.json
--- a/substrate/serai/client/src/in_instructions.rs
+++ b/substrate/serai/client/src/in_instructions.rs
@ -1,15 +1,9 @@
-use scale::Decode;
-
-use serai_runtime::{
-  support::traits::PalletInfo as PalletInfoTrait, PalletInfo, in_instructions, InInstructions,
-  Runtime,
-};
-
-pub use in_instructions_primitives as primitives;
+use serai_runtime::{in_instructions, InInstructions, Runtime};
+pub use in_instructions::primitives;

 use crate::{
  primitives::{Coin, BlockNumber},
-  Serai, SeraiError,
+  Serai, SeraiError, scale_value,
 };

 const PALLET: &str = "InInstructions";
@ -21,22 +15,11 @@ impl Serai {
    &self,
    block: [u8; 32],
  ) -> Result<Vec<InInstructionsEvent>, SeraiError> {
-    let mut res = vec![];
-    for event in
-      self.0.events().at(Some(block.into())).await.map_err(|_| SeraiError::RpcError)?.iter()
-    {
-      let event = event.map_err(|_| SeraiError::InvalidRuntime)?;
-      if PalletInfo::index::<InInstructions>().unwrap() == usize::from(event.pallet_index()) {
-        let mut with_variant: &[u8] =
-          &[[event.variant_index()].as_ref(), event.field_bytes()].concat();
-        let event =
-          InInstructionsEvent::decode(&mut with_variant).map_err(|_| SeraiError::InvalidRuntime)?;
-        if matches!(event, InInstructionsEvent::Batch { .. }) {
-          res.push(event);
-        }
-      }
-    }
-    Ok(res)
+    self
+      .events::<InInstructions, _>(block, |event| {
+        matches!(event, InInstructionsEvent::Batch { .. })
+      })
+      .await
  }

  pub async fn get_coin_block_number(
@ -44,6 +27,11 @@ impl Serai {
    coin: Coin,
    block: [u8; 32],
  ) -> Result<BlockNumber, SeraiError> {
-    Ok(self.storage(PALLET, "BlockNumbers", Some(coin), block).await?.unwrap_or(BlockNumber(0)))
+    Ok(
+      self
+        .storage(PALLET, "BlockNumbers", Some(vec![scale_value(coin)]), block)
+        .await?
+        .unwrap_or(BlockNumber(0)),
+    )
  }
 }
--- a/substrate/serai/client/src/lib.rs
+++ b/substrate/serai/client/src/lib.rs
@ -1,19 +1,36 @@
 use thiserror::Error;

-use serde::Serialize;
-use scale::Decode;
+use scale::{Encode, Decode};
+mod scale_value;
+pub(crate) use crate::scale_value::{scale_value, scale_composite};
+use ::scale_value::Value;

-use subxt::{tx::BaseExtrinsicParams, Config as SubxtConfig, OnlineClient};
+use subxt::{
+  utils::Encoded,
+  tx::{
+    Signer, DynamicTxPayload, BaseExtrinsicParams, BaseExtrinsicParamsBuilder, TxClient,
+  },
+  Config as SubxtConfig, OnlineClient,
+};

 pub use serai_primitives as primitives;
 use primitives::{Signature, SeraiAddress};

-use serai_runtime::{system::Config, Runtime};
+use serai_runtime::{
+  system::Config, support::traits::PalletInfo as PalletInfoTrait, PalletInfo, Runtime,
+};

+pub mod tokens;
 pub mod in_instructions;

+#[derive(Clone, Copy, PartialEq, Eq, Default, Debug, Encode, Decode)]
+pub struct Tip {
+  #[codec(compact)]
+  pub tip: u64,
+}
+
 #[derive(Clone, Copy, PartialEq, Eq, Debug)]
-pub(crate) struct SeraiConfig;
+pub struct SeraiConfig;
 impl SubxtConfig for SeraiConfig {
  type BlockNumber = <Runtime as Config>::BlockNumber;

@ -28,7 +45,7 @@ impl SubxtConfig for SeraiConfig {
  type Header = <Runtime as Config>::Header;
  type Signature = Signature;

-  type ExtrinsicParams = BaseExtrinsicParams<SeraiConfig, ()>;
+  type ExtrinsicParams = BaseExtrinsicParams<SeraiConfig, Tip>;
 }

 #[derive(Clone, Error, Debug)]
@ -47,21 +64,16 @@ impl Serai {
    Ok(Serai(OnlineClient::<SeraiConfig>::from_url(url).await.map_err(|_| SeraiError::RpcError)?))
  }

-  async fn storage<K: Serialize, R: Decode>(
+  async fn storage<R: Decode>(
    &self,
    pallet: &'static str,
    name: &'static str,
-    key: Option<K>,
+    keys: Option<Vec<Value>>,
    block: [u8; 32],
  ) -> Result<Option<R>, SeraiError> {
-    let mut keys = vec![];
-    if let Some(key) = key {
-      keys.push(scale_value::serde::to_value(key).unwrap());
-    }
-
    let storage = self.0.storage();
-    let address = subxt::dynamic::storage(pallet, name, keys);
-    debug_assert!(storage.validate(&address).is_ok());
+    let address = subxt::dynamic::storage(pallet, name, keys.unwrap_or(vec![]));
+    debug_assert!(storage.validate(&address).is_ok(), "invalid storage address");

    storage
      .fetch(&address, Some(block.into()))
@ -71,7 +83,46 @@ impl Serai {
      .transpose()
  }

+  async fn events<P: 'static, E: Decode>(
+    &self,
+    block: [u8; 32],
+    filter: impl Fn(&E) -> bool,
+  ) -> Result<Vec<E>, SeraiError> {
+    let mut res = vec![];
+    for event in
+      self.0.events().at(Some(block.into())).await.map_err(|_| SeraiError::RpcError)?.iter()
+    {
+      let event = event.map_err(|_| SeraiError::InvalidRuntime)?;
+      if PalletInfo::index::<P>().unwrap() == usize::from(event.pallet_index()) {
+        let mut with_variant: &[u8] =
+          &[[event.variant_index()].as_ref(), event.field_bytes()].concat();
+        let event = E::decode(&mut with_variant).map_err(|_| SeraiError::InvalidRuntime)?;
+        if filter(&event) {
+          res.push(event);
+        }
+      }
+    }
+    Ok(res)
+  }
+
  pub async fn get_latest_block_hash(&self) -> Result<[u8; 32], SeraiError> {
    Ok(self.0.rpc().finalized_head().await.map_err(|_| SeraiError::RpcError)?.into())
  }
+
+  pub fn sign<S: Send + Sync + Signer<SeraiConfig>>(
+    &self,
+    signer: &S,
+    payload: &DynamicTxPayload<'static>,
+    nonce: u32,
+    params: BaseExtrinsicParamsBuilder<SeraiConfig, Tip>,
+  ) -> Result<Encoded, SeraiError> {
+    TxClient::new(self.0.offline())
+      .create_signed_with_nonce(payload, signer, nonce, params)
+      .map(|tx| Encoded(tx.into_encoded()))
+      .map_err(|_| SeraiError::InvalidRuntime)
+  }
+
+  pub async fn publish(&self, tx: &Encoded) -> Result<[u8; 32], SeraiError> {
+    self.0.rpc().submit_extrinsic(tx).await.map(Into::into).map_err(|_| SeraiError::RpcError)
+  }
 }
--- a/substrate/serai/client/src/scale_value.rs
+++ b/substrate/serai/client/src/scale_value.rs
@ -0,0 +1,18 @@
+use ::scale::Encode;
+use scale_info::{MetaType, TypeInfo, Registry, PortableRegistry};
+use scale_value::{Composite, ValueDef, Value, scale};
+
+pub(crate) fn scale_value<V: Encode + TypeInfo + 'static>(value: V) -> Value {
+  let mut registry = Registry::new();
+  let id = registry.register_type(&MetaType::new::<V>()).id();
+  let registry = PortableRegistry::from(registry);
+  scale::decode_as_type(&mut value.encode().as_ref(), id, &registry).unwrap().remove_context()
+}
+
+pub(crate) fn scale_composite<V: Encode + TypeInfo + 'static>(value: V) -> Composite<()> {
+  match scale_value(value).value {
+    ValueDef::Composite(composite) => composite,
+    ValueDef::Variant(variant) => variant.values,
+    _ => panic!("not composite"),
+  }
+}
--- a/substrate/serai/client/src/tokens.rs
+++ b/substrate/serai/client/src/tokens.rs
@ -0,0 +1,68 @@
+use serai_runtime::{
+  primitives::{SeraiAddress, SubstrateAmount, Amount, Coin, Balance},
+  assets::{AssetDetails, AssetAccount},
+  tokens, Tokens, Runtime,
+};
+pub use tokens::primitives;
+use primitives::OutInstruction;
+
+use subxt::tx::{self, DynamicTxPayload};
+
+use crate::{Serai, SeraiError, scale_value, scale_composite};
+
+const PALLET: &str = "Tokens";
+
+pub type TokensEvent = tokens::Event<Runtime>;
+
+impl Serai {
+  pub async fn get_mint_events(&self, block: [u8; 32]) -> Result<Vec<TokensEvent>, SeraiError> {
+    self.events::<Tokens, _>(block, |event| matches!(event, TokensEvent::Mint { .. })).await
+  }
+
+  pub async fn get_token_supply(&self, block: [u8; 32], coin: Coin) -> Result<Amount, SeraiError> {
+    Ok(Amount(
+      self
+        .storage::<AssetDetails<SubstrateAmount, SeraiAddress, SubstrateAmount>>(
+          "Assets",
+          "Asset",
+          Some(vec![scale_value(coin)]),
+          block,
+        )
+        .await?
+        .map(|token| token.supply)
+        .unwrap_or(0),
+    ))
+  }
+
+  pub async fn get_token_balance(
+    &self,
+    block: [u8; 32],
+    coin: Coin,
+    address: SeraiAddress,
+  ) -> Result<Amount, SeraiError> {
+    Ok(Amount(
+      self
+        .storage::<AssetAccount<SubstrateAmount, SubstrateAmount, ()>>(
+          "Assets",
+          "Account",
+          Some(vec![scale_value(coin), scale_value(address)]),
+          block,
+        )
+        .await?
+        .map(|account| account.balance)
+        .unwrap_or(0),
+    ))
+  }
+
+  pub fn burn(balance: Balance, instruction: OutInstruction) -> DynamicTxPayload<'static> {
+    tx::dynamic(
+      PALLET,
+      "burn",
+      scale_composite(tokens::Call::<Runtime>::burn { balance, instruction }),
+    )
+  }
+
+  pub async fn get_burn_events(&self, block: [u8; 32]) -> Result<Vec<TokensEvent>, SeraiError> {
+    self.events::<Tokens, _>(block, |event| matches!(event, TokensEvent::Burn { .. })).await
+  }
+}
--- a/substrate/serai/client/tests/burn.rs
+++ b/substrate/serai/client/tests/burn.rs
@ -0,0 +1,79 @@
+use core::time::Duration;
+
+use rand_core::{RngCore, OsRng};
+
+use sp_core::Pair;
+use serai_runtime::in_instructions::{Batch, Update};
+
+use tokio::time::sleep;
+
+use subxt::tx::{BaseExtrinsicParamsBuilder, PairSigner};
+
+use serai_client::{
+  primitives::{
+    BITCOIN, BlockNumber, BlockHash, SeraiAddress, Amount, WithAmount, Balance, Data,
+    ExternalAddress, insecure_pair_from_name,
+  },
+  in_instructions::primitives::InInstruction,
+  tokens::{primitives::OutInstruction, TokensEvent},
+  Serai,
+};
+
+mod runner;
+use runner::{URL, provide_updates};
+
+serai_test!(
+  async fn burn() {
+    let coin = BITCOIN;
+    let mut id = BlockHash([0; 32]);
+    OsRng.fill_bytes(&mut id.0);
+    let block_number = BlockNumber(u32::try_from(OsRng.next_u64() >> 32).unwrap());
+
+    let pair = insecure_pair_from_name("Alice");
+    let public = pair.public();
+    let address = SeraiAddress::from(public);
+
+    let amount = Amount(OsRng.next_u64());
+    let balance = Balance { coin, amount };
+
+    let mut rand_bytes = vec![0; 32];
+    OsRng.fill_bytes(&mut rand_bytes);
+    let external_address = ExternalAddress::new(rand_bytes).unwrap();
+
+    let mut rand_bytes = vec![0; 32];
+    OsRng.fill_bytes(&mut rand_bytes);
+    let data = Data::new(rand_bytes).unwrap();
+
+    let batch = Batch {
+      id,
+      instructions: vec![WithAmount { data: InInstruction::Transfer(address), amount }],
+    };
+    let update = Update { block_number, batches: vec![batch] };
+    let block = provide_updates(vec![Some(update)]).await;
+
+    let serai = Serai::new(URL).await.unwrap();
+    assert_eq!(serai.get_token_balance(block, coin, address).await.unwrap(), amount);
+
+    let out = OutInstruction { address: external_address, data: Some(data) };
+    let burn = Serai::burn(balance, out.clone());
+
+    let signer = PairSigner::new(pair);
+    serai
+      .publish(&serai.sign(&signer, &burn, 0, BaseExtrinsicParamsBuilder::new()).unwrap())
+      .await
+      .unwrap();
+
+    loop {
+      let block = serai.get_latest_block_hash().await.unwrap();
+      let events = serai.get_burn_events(block).await.unwrap();
+      if events.is_empty() {
+        sleep(Duration::from_millis(50)).await;
+        continue;
+      }
+      assert_eq!(events, vec![TokensEvent::Burn { address, balance, instruction: out }]);
+      assert_eq!(serai.get_token_supply(block, coin).await.unwrap(), Amount(0));
+      assert_eq!(serai.get_token_balance(block, coin, address).await.unwrap(), Amount(0));
+      break;
+    }
+  }
+);
--- a/substrate/serai/client/tests/runner.rs
+++ b/substrate/serai/client/tests/runner.rs
@ -1,6 +1,14 @@
+use core::time::Duration;
+use std::sync::Arc;
+
 use lazy_static::lazy_static;

-use tokio::sync::Mutex;
+use tokio::{sync::Mutex, time::sleep};
+
+use serai_runtime::in_instructions::Update;
+use serai_client::{primitives::Coin, in_instructions::InInstructionsEvent, Serai};
+
+use jsonrpsee_server::RpcModule;

 pub const URL: &str = "ws://127.0.0.1:9944";

@ -8,6 +16,73 @@ lazy_static! {
  pub static ref SEQUENTIAL: Mutex<()> = Mutex::new(());
 }

+#[allow(dead_code)]
+pub async fn provide_updates(updates: Vec<Option<Update>>) -> [u8; 32] {
+  let done = Arc::new(Mutex::new(false));
+  let done_clone = done.clone();
+  let updates_clone = updates.clone();
+
+  let mut rpc = RpcModule::new(());
+  rpc
+    .register_async_method("processor_coinUpdates", move |_, _| {
+      let done_clone = done_clone.clone();
+      let updates_clone = updates_clone.clone();
+      async move {
+        // Sleep to prevent a race condition where we submit the inherents for this block and the
+        // next one, then remove them, making them unverifiable, causing the node to panic for
+        // being self-malicious
+        sleep(Duration::from_millis(500)).await;
+        if !*done_clone.lock().await {
+          Ok(updates_clone)
+        } else {
+          Ok(vec![])
+        }
+      }
+    })
+    .unwrap();
+  let _handle = jsonrpsee_server::ServerBuilder::default()
+    .build("127.0.0.1:5134")
+    .await
+    .unwrap()
+    .start(rpc)
+    .unwrap();
+
+  let serai = Serai::new(URL).await.unwrap();
+  loop {
+    let latest = serai.get_latest_block_hash().await.unwrap();
+    let mut batches = serai.get_batch_events(latest).await.unwrap();
+    if batches.is_empty() {
+      sleep(Duration::from_millis(50)).await;
+      continue;
+    }
+    *done.lock().await = true;
+
+    for (index, update) in updates.iter().enumerate() {
+      if let Some(update) = update {
+        let coin_by_index = Coin(u32::try_from(index).unwrap() + 1);
+
+        for expected in &update.batches {
+          match batches.swap_remove(0) {
+            InInstructionsEvent::Batch { coin, id } => {
+              assert_eq!(coin, coin_by_index);
+              assert_eq!(expected.id, id);
+            }
+            _ => panic!("get_batches returned non-batch"),
+          }
+        }
+        assert_eq!(
+          serai.get_coin_block_number(coin_by_index, latest).await.unwrap(),
+          update.block_number
+        );
+      }
+    }
+    // This will fail if there were more batch events than expected
+    assert!(batches.is_empty());
+
+    return latest;
+  }
+}
+
 #[macro_export]
 macro_rules! serai_test {
  ($(async fn $name: ident() $body: block)*) => {
--- a/substrate/serai/client/tests/updates.rs
+++ b/substrate/serai/client/tests/updates.rs
@ -1,60 +1,45 @@
-use core::time::Duration;
-
-use tokio::time::sleep;
+use rand_core::{RngCore, OsRng};

 use serai_runtime::in_instructions::{Batch, Update};

-use jsonrpsee_server::RpcModule;
-
 use serai_client::{
-  primitives::{BlockNumber, BlockHash, SeraiAddress, BITCOIN},
+  primitives::{BITCOIN, BlockNumber, BlockHash, SeraiAddress, Amount, WithAmount, Balance},
+  tokens::TokensEvent,
  in_instructions::{primitives::InInstruction, InInstructionsEvent},
  Serai,
 };

 mod runner;
-use runner::URL;
+use runner::{URL, provide_updates};

 serai_test!(
-  async fn publish_update() {
-    let mut rpc = RpcModule::new(());
-    rpc
-      .register_async_method("processor_coinUpdates", |_, _| async move {
-        let batch = Batch {
-          id: BlockHash([0xaa; 32]),
-          instructions: vec![InInstruction::Transfer(SeraiAddress::from_raw([0xff; 32]))],
-        };
+  async fn publish_updates() {
+    let coin = BITCOIN;
+    let mut id = BlockHash([0; 32]);
+    OsRng.fill_bytes(&mut id.0);
+    let block_number = BlockNumber(u32::try_from(OsRng.next_u64() >> 32).unwrap());

-        Ok(vec![Some(Update { block_number: BlockNumber(123), batches: vec![batch] })])
-      })
-      .unwrap();
+    let mut address = SeraiAddress::new([0; 32]);
+    OsRng.fill_bytes(&mut address.0);
+    let amount = Amount(OsRng.next_u64());

-    let _handle = jsonrpsee_server::ServerBuilder::default()
-      .build("127.0.0.1:5134")
-      .await
-      .unwrap()
-      .start(rpc)
-      .unwrap();
+    let batch = Batch {
+      id,
+      instructions: vec![WithAmount { data: InInstruction::Transfer(address), amount }],
+    };
+    let update = Update { block_number, batches: vec![batch] };
+    let block = provide_updates(vec![Some(update)]).await;

    let serai = Serai::new(URL).await.unwrap();
-    loop {
-      let latest = serai.get_latest_block_hash().await.unwrap();
-      let batches = serai.get_batch_events(latest).await.unwrap();
-      if let Some(batch) = batches.get(0) {
-        match batch {
-          InInstructionsEvent::Batch { coin, id } => {
-            assert_eq!(coin, &BITCOIN);
-            assert_eq!(id, &BlockHash([0xaa; 32]));
-            assert_eq!(
-              serai.get_coin_block_number(BITCOIN, latest).await.unwrap(),
-              BlockNumber(123)
-            );
-            return;
-          }
-          _ => panic!("get_batches returned non-batch"),
-        }
-      }
-      sleep(Duration::from_millis(50)).await;
-    }
+    let batches = serai.get_batch_events(block).await.unwrap();
+    assert_eq!(batches, vec![InInstructionsEvent::Batch { coin, id }]);
+    assert_eq!(serai.get_coin_block_number(coin, block).await.unwrap(), block_number);
+
+    assert_eq!(
+      serai.get_mint_events(block).await.unwrap(),
+      vec![TokensEvent::Mint { address, balance: Balance { coin, amount } }]
+    );
+    assert_eq!(serai.get_token_supply(block, coin).await.unwrap(), amount);
+    assert_eq!(serai.get_token_balance(block, coin, address).await.unwrap(), amount);
  }
 );
--- a/substrate/serai/primitives/Cargo.toml
+++ b/substrate/serai/primitives/Cargo.toml
@ -18,7 +18,8 @@ scale-info = { version = "2", default-features = false, features = ["derive"] }
 serde = { version = "1", features = ["derive"], optional = true }

 sp-core = { git = "https://github.com/serai-dex/substrate", default-features = false }
+sp-runtime = { git = "https://github.com/serai-dex/substrate", default-features = false }

 [features]
-std = ["scale/std", "scale-info/std", "serde", "sp-core/std"]
+std = ["scale/std", "scale-info/std", "serde", "sp-core/std", "sp-runtime/std"]
 default = ["std"]
--- a/substrate/serai/primitives/src/account.rs
+++ b/substrate/serai/primitives/src/account.rs
@ -0,0 +1,93 @@
+use scale::{Encode, Decode, MaxEncodedLen};
+use scale_info::TypeInfo;
+#[cfg(feature = "std")]
+use serde::{Serialize, Deserialize};
+
+use sp_core::sr25519::{Public, Signature as RistrettoSignature};
+#[cfg(feature = "std")]
+use sp_core::{Pair as PairTrait, sr25519::Pair};
+
+use sp_runtime::traits::{LookupError, Lookup, StaticLookup};
+
+pub type PublicKey = Public;
+
+#[derive(
+  Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Debug, Encode, Decode, MaxEncodedLen, TypeInfo,
+)]
+#[cfg_attr(feature = "std", derive(Serialize, Deserialize))]
+pub struct SeraiAddress(pub [u8; 32]);
+impl SeraiAddress {
+  pub fn new(key: [u8; 32]) -> SeraiAddress {
+    SeraiAddress(key)
+  }
+}
+
+impl From<[u8; 32]> for SeraiAddress {
+  fn from(key: [u8; 32]) -> SeraiAddress {
+    SeraiAddress(key)
+  }
+}
+
+impl From<PublicKey> for SeraiAddress {
+  fn from(key: PublicKey) -> SeraiAddress {
+    SeraiAddress(key.0)
+  }
+}
+
+impl From<SeraiAddress> for PublicKey {
+  fn from(address: SeraiAddress) -> PublicKey {
+    PublicKey::from_raw(address.0)
+  }
+}
+
+#[cfg(feature = "std")]
+impl std::fmt::Display for SeraiAddress {
+  fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+    // TODO: Bech32
+    write!(f, "{:?}", self.0)
+  }
+}
+
+#[cfg(feature = "std")]
+pub fn insecure_pair_from_name(name: &'static str) -> Pair {
+  Pair::from_string(&format!("//{name}"), None).unwrap()
+}
+
+pub struct AccountLookup;
+impl Lookup for AccountLookup {
+  type Source = SeraiAddress;
+  type Target = PublicKey;
+  fn lookup(&self, source: SeraiAddress) -> Result<PublicKey, LookupError> {
+    Ok(PublicKey::from_raw(source.0))
+  }
+}
+impl StaticLookup for AccountLookup {
+  type Source = SeraiAddress;
+  type Target = PublicKey;
+  fn lookup(source: SeraiAddress) -> Result<PublicKey, LookupError> {
+    Ok(source.into())
+  }
+  fn unlookup(source: PublicKey) -> SeraiAddress {
+    source.into()
+  }
+}
+
+pub type Signature = RistrettoSignature;
+
+pub const fn pallet_address(pallet: &'static [u8]) -> SeraiAddress {
+  let mut address = [0; 32];
+  let mut set = false;
+  // Implement a while loop since we can't use a for loop
+  let mut i = 0;
+  while i < pallet.len() {
+    address[i] = pallet[i];
+    if address[i] != 0 {
+      set = true;
+    }
+    i += 1;
+  }
+  // Make sure this address isn't the identity point
+  // Doesn't do address != [0; 32] since that's not const
+  assert!(set, "address is the identity point");
+  SeraiAddress(address)
+}
--- a/substrate/serai/primitives/src/amount.rs
+++ b/substrate/serai/primitives/src/amount.rs
@ -1,20 +1,25 @@
-use core::ops::{Add, Sub, Mul};
+use core::{
+  ops::{Add, Sub, Mul},
+  fmt::Debug,
+};

 use scale::{Encode, Decode, MaxEncodedLen};
 use scale_info::TypeInfo;
 #[cfg(feature = "std")]
 use serde::{Serialize, Deserialize};

+/// The type used for amounts within Substrate.
+// Distinct from Amount due to Substrate's requirements on this type.
+// While Amount could have all the necessary traits implemented, not only are they many, it'd make
+// Amount a large type with a variety of misc functions.
+// The current type's minimalism sets clear bounds on usage.
+pub type SubstrateAmount = u64;
 /// The type used for amounts.
 #[derive(
  Clone, Copy, PartialEq, Eq, PartialOrd, Debug, Encode, Decode, MaxEncodedLen, TypeInfo,
 )]
 #[cfg_attr(feature = "std", derive(Serialize, Deserialize))]
-pub struct Amount(pub u64);
-
-/// One whole coin with eight decimals.
-#[allow(clippy::inconsistent_digit_grouping)]
-pub const COIN: Amount = Amount(1_000_000_00);
+pub struct Amount(pub SubstrateAmount);

 impl Add for Amount {
  type Output = Amount;
@ -37,3 +42,12 @@ impl Mul for Amount {
    Amount(self.0.checked_mul(other.0).unwrap())
  }
 }
+
+#[derive(Clone, PartialEq, Eq, Debug, Encode, Decode, MaxEncodedLen, TypeInfo)]
+#[cfg_attr(feature = "std", derive(Serialize, Deserialize))]
+pub struct WithAmount<
+  T: Clone + PartialEq + Eq + Debug + Encode + Decode + MaxEncodedLen + TypeInfo,
+> {
+  pub data: T,
+  pub amount: Amount,
+}
--- a/substrate/serai/primitives/src/balance.rs
+++ b/substrate/serai/primitives/src/balance.rs
@ -0,0 +1,37 @@
+use core::ops::{Add, Sub, Mul};
+
+use scale::{Encode, Decode, MaxEncodedLen};
+use scale_info::TypeInfo;
+#[cfg(feature = "std")]
+use serde::{Serialize, Deserialize};
+
+use crate::{Coin, Amount};
+
+/// The type used for balances (a Coin and Balance).
+#[derive(Clone, Copy, PartialEq, Eq, Debug, Encode, Decode, MaxEncodedLen, TypeInfo)]
+#[cfg_attr(feature = "std", derive(Serialize, Deserialize))]
+pub struct Balance {
+  pub coin: Coin,
+  pub amount: Amount,
+}
+
+impl Add<Amount> for Balance {
+  type Output = Balance;
+  fn add(self, other: Amount) -> Balance {
+    Balance { coin: self.coin, amount: self.amount + other }
+  }
+}
+
+impl Sub<Amount> for Balance {
+  type Output = Balance;
+  fn sub(self, other: Amount) -> Balance {
+    Balance { coin: self.coin, amount: self.amount - other }
+  }
+}
+
+impl Mul<Amount> for Balance {
+  type Output = Balance;
+  fn mul(self, other: Amount) -> Balance {
+    Balance { coin: self.coin, amount: self.amount * other }
+  }
+}
--- a/substrate/serai/primitives/src/block.rs
+++ b/substrate/serai/primitives/src/block.rs
@ -0,0 +1,46 @@
+use scale::{Encode, Decode, MaxEncodedLen};
+use scale_info::TypeInfo;
+#[cfg(feature = "std")]
+use serde::{Serialize, Deserialize};
+
+use sp_core::H256;
+
+/// The type used to identify block numbers.
+// Doesn't re-export tendermint-machine's due to traits.
+#[derive(
+  Clone, Copy, Default, PartialEq, Eq, Hash, Debug, Encode, Decode, MaxEncodedLen, TypeInfo,
+)]
+#[cfg_attr(feature = "std", derive(Serialize, Deserialize))]
+pub struct BlockNumber(pub u32);
+impl From<u32> for BlockNumber {
+  fn from(number: u32) -> BlockNumber {
+    BlockNumber(number)
+  }
+}
+
+/// The type used to identify block hashes.
+// This may not be universally compatible
+// If a block exists with a hash which isn't 32-bytes, it can be hashed into a value with 32-bytes
+// This would require the processor to maintain a mapping of 32-byte IDs to actual hashes, which
+// would be fine
+#[derive(Clone, Copy, PartialEq, Eq, Hash, Debug, Encode, Decode, MaxEncodedLen, TypeInfo)]
+#[cfg_attr(feature = "std", derive(Serialize, Deserialize))]
+pub struct BlockHash(pub [u8; 32]);
+
+impl AsRef<[u8]> for BlockHash {
+  fn as_ref(&self) -> &[u8] {
+    self.0.as_ref()
+  }
+}
+
+impl From<[u8; 32]> for BlockHash {
+  fn from(hash: [u8; 32]) -> BlockHash {
+    BlockHash(hash)
+  }
+}
+
+impl From<H256> for BlockHash {
+  fn from(hash: H256) -> BlockHash {
+    BlockHash(hash.into())
+  }
+}
--- a/substrate/serai/primitives/src/lib.rs
+++ b/substrate/serai/primitives/src/lib.rs
@ -7,57 +7,75 @@ use scale_info::TypeInfo;
 #[cfg(feature = "std")]
 use serde::{Serialize, Deserialize};

-use sp_core::{
-  H256,
-  sr25519::{Public, Signature as RistrettoSignature},
-};
+use sp_core::{ConstU32, bounded::BoundedVec};

 mod amount;
 pub use amount::*;

+mod block;
+pub use block::*;
+
 mod coins;
 pub use coins::*;

-pub type PublicKey = Public;
-pub type SeraiAddress = PublicKey;
-pub type Signature = RistrettoSignature;
+mod balance;
+pub use balance::*;

-/// The type used to identify block numbers.
-// Doesn't re-export tendermint-machine's due to traits.
-#[derive(
-  Clone, Copy, Default, PartialEq, Eq, Hash, Debug, Encode, Decode, MaxEncodedLen, TypeInfo,
-)]
+mod account;
+pub use account::*;
+
+// Monero, our current longest address candidate, has a longest address of featured with payment ID
+// 1 (enum) + 1 (flags) + 64 (two keys) + 8 (payment ID) = 74
+pub const MAX_ADDRESS_LEN: u32 = 74;
+
+#[derive(Clone, PartialEq, Eq, Debug, Encode, Decode, MaxEncodedLen, TypeInfo)]
 #[cfg_attr(feature = "std", derive(Serialize, Deserialize))]
-pub struct BlockNumber(pub u32);
-impl From<u32> for BlockNumber {
-  fn from(number: u32) -> BlockNumber {
-    BlockNumber(number)
+pub struct ExternalAddress(BoundedVec<u8, ConstU32<{ MAX_ADDRESS_LEN }>>);
+impl ExternalAddress {
+  #[cfg(feature = "std")]
+  pub fn new(address: Vec<u8>) -> Result<ExternalAddress, &'static str> {
+    Ok(ExternalAddress(address.try_into().map_err(|_| "address length exceeds {MAX_ADDRESS_LEN}")?))
+  }
+
+  pub fn address(&self) -> &[u8] {
+    self.0.as_ref()
+  }
+
+  #[cfg(feature = "std")]
+  pub fn consume(self) -> Vec<u8> {
+    self.0.into_inner()
  }
 }

-/// The type used to identify block hashes.
-// This may not be universally compatible
-// If a block exists with a hash which isn't 32-bytes, it can be hashed into a value with 32-bytes
-// This would require the processor to maintain a mapping of 32-byte IDs to actual hashes, which
-// would be fine
-#[derive(Clone, Copy, PartialEq, Eq, Hash, Debug, Encode, Decode, MaxEncodedLen, TypeInfo)]
-#[cfg_attr(feature = "std", derive(Serialize, Deserialize))]
-pub struct BlockHash(pub [u8; 32]);
-
-impl AsRef<[u8]> for BlockHash {
+impl AsRef<[u8]> for ExternalAddress {
  fn as_ref(&self) -> &[u8] {
    self.0.as_ref()
  }
 }

-impl From<[u8; 32]> for BlockHash {
-  fn from(hash: [u8; 32]) -> BlockHash {
-    BlockHash(hash)
+// Should be enough for a Uniswap v3 call
+pub const MAX_DATA_LEN: u32 = 512;
+#[derive(Clone, PartialEq, Eq, Debug, Encode, Decode, MaxEncodedLen, TypeInfo)]
+#[cfg_attr(feature = "std", derive(Serialize, Deserialize))]
+pub struct Data(BoundedVec<u8, ConstU32<{ MAX_DATA_LEN }>>);
+impl Data {
+  #[cfg(feature = "std")]
+  pub fn new(data: Vec<u8>) -> Result<Data, &'static str> {
+    Ok(Data(data.try_into().map_err(|_| "data length exceeds {MAX_DATA_LEN}")?))
+  }
+
+  pub fn data(&self) -> &[u8] {
+    self.0.as_ref()
+  }
+
+  #[cfg(feature = "std")]
+  pub fn consume(self) -> Vec<u8> {
+    self.0.into_inner()
  }
 }

-impl From<H256> for BlockHash {
-  fn from(hash: H256) -> BlockHash {
-    BlockHash(hash.into())
+impl AsRef<[u8]> for Data {
+  fn as_ref(&self) -> &[u8] {
+    self.0.as_ref()
  }
 }
--- a/substrate/tokens/pallet/Cargo.toml
+++ b/substrate/tokens/pallet/Cargo.toml
@ -0,0 +1,38 @@
+[package]
+name = "tokens-pallet"
+version = "0.1.0"
+description = "Mint and burn Serai tokens"
+license = "AGPL-3.0-only"
+authors = ["Luke Parker <lukeparker5132@gmail.com>"]
+edition = "2021"
+publish = false
+
+[package.metadata.docs.rs]
+all-features = true
+rustdoc-args = ["--cfg", "docsrs"]
+
+[dependencies]
+scale = { package = "parity-scale-codec", version = "3", default-features = false, features = ["derive", "max-encoded-len"] }
+scale-info = { version = "2", default-features = false, features = ["derive"] }
+
+frame-system = { git = "https://github.com/serai-dex/substrate", default-features = false }
+frame-support = { git = "https://github.com/serai-dex/substrate", default-features = false }
+
+pallet-assets = { git = "https://github.com/serai-dex/substrate", default-features = false }
+
+serai-primitives = { path = "../../serai/primitives", default-features = false }
+tokens-primitives = { path = "../primitives", default-features = false }
+
+[features]
+std = [
+  "scale/std",
+  "scale-info/std",
+
+  "frame-system/std",
+  "frame-support/std",
+
+  "pallet-assets/std",
+
+  "serai-primitives/std",
+]
+default = ["std"]
--- a/substrate/tokens/pallet/LICENSE
+++ b/substrate/tokens/pallet/LICENSE
@ -0,0 +1,15 @@
+AGPL-3.0-only license
+
+Copyright (c) 2023 Luke Parker
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU Affero General Public License Version 3 as
+published by the Free Software Foundation.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU Affero General Public License for more details.
+
+You should have received a copy of the GNU Affero General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
--- a/substrate/tokens/pallet/src/lib.rs
+++ b/substrate/tokens/pallet/src/lib.rs
@ -0,0 +1,83 @@
+#![cfg_attr(docsrs, feature(doc_cfg))]
+#![cfg_attr(docsrs, feature(doc_auto_cfg))]
+#![cfg_attr(not(feature = "std"), no_std)]
+
+pub use tokens_primitives as primitives;
+
+#[frame_support::pallet]
+pub mod pallet {
+  use frame_support::pallet_prelude::*;
+  use frame_system::{pallet_prelude::*, RawOrigin};
+
+  use pallet_assets::{Config as AssetsConfig, Pallet as AssetsPallet};
+
+  use serai_primitives::{SubstrateAmount, Coin, Balance, PublicKey, SeraiAddress, AccountLookup};
+  use primitives::{ADDRESS, OutInstruction};
+
+  use super::*;
+
+  #[pallet::config]
+  pub trait Config:
+    frame_system::Config<AccountId = PublicKey, Lookup = AccountLookup>
+    + AssetsConfig<AssetIdParameter = Coin, Balance = SubstrateAmount>
+  {
+    type RuntimeEvent: From<Event<Self>> + IsType<<Self as frame_system::Config>::RuntimeEvent>;
+  }
+
+  #[pallet::event]
+  #[pallet::generate_deposit(fn deposit_event)]
+  pub enum Event<T: Config> {
+    // Mint is technically redundant as the assets pallet has the exact same event already
+    // Providing our own definition here just helps consolidate code
+    Mint { address: SeraiAddress, balance: Balance },
+    Burn { address: SeraiAddress, balance: Balance, instruction: OutInstruction },
+  }
+
+  #[pallet::pallet]
+  #[pallet::generate_store(pub(crate) trait Store)]
+  pub struct Pallet<T>(PhantomData<T>);
+
+  impl<T: Config> Pallet<T> {
+    fn burn_internal(
+      address: SeraiAddress,
+      balance: Balance,
+      instruction: OutInstruction,
+    ) -> DispatchResult {
+      AssetsPallet::<T>::burn(
+        RawOrigin::Signed(ADDRESS.into()).into(),
+        balance.coin,
+        address,
+        balance.amount.0,
+      )?;
+      Pallet::<T>::deposit_event(Event::Burn { address, balance, instruction });
+      Ok(())
+    }
+
+    pub fn mint(address: SeraiAddress, balance: Balance) {
+      // TODO: Prevent minting when it'd cause an amount exceeding the bond
+      AssetsPallet::<T>::mint(
+        RawOrigin::Signed(ADDRESS.into()).into(),
+        balance.coin,
+        address,
+        balance.amount.0,
+      )
+      .unwrap();
+      Pallet::<T>::deposit_event(Event::Mint { address, balance });
+    }
+  }
+
+  #[pallet::call]
+  impl<T: Config> Pallet<T> {
+    #[pallet::call_index(0)]
+    #[pallet::weight((0, DispatchClass::Normal))] // TODO
+    pub fn burn(
+      origin: OriginFor<T>,
+      balance: Balance,
+      instruction: OutInstruction,
+    ) -> DispatchResult {
+      Self::burn_internal(ensure_signed(origin)?.into(), balance, instruction)
+    }
+  }
+}
+
+pub use pallet::*;
--- a/substrate/tokens/primitives/Cargo.toml
+++ b/substrate/tokens/primitives/Cargo.toml
@ -0,0 +1,26 @@
+[package]
+name = "tokens-primitives"
+version = "0.1.0"
+description = "Serai tokens primitives"
+license = "MIT"
+authors = ["Luke Parker <lukeparker5132@gmail.com>"]
+edition = "2021"
+
+[package.metadata.docs.rs]
+all-features = true
+rustdoc-args = ["--cfg", "docsrs"]
+
+[dependencies]
+scale = { package = "parity-scale-codec", version = "3", default-features = false, features = ["derive"] }
+scale-info = { version = "2", default-features = false, features = ["derive"] }
+
+serde = { version = "1", features = ["derive"], optional = true }
+
+serai-primitives = { path = "../../serai/primitives", default-features = false }
+
+[dev-dependencies]
+sp-runtime = { git = "https://github.com/serai-dex/substrate", default-features = false }
+
+[features]
+std = ["scale/std", "scale-info/std", "serde", "sp-runtime/std", "serai-primitives/std"]
+default = ["std"]
--- a/substrate/tokens/primitives/LICENSE
+++ b/substrate/tokens/primitives/LICENSE
@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2023 Luke Parker
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
--- a/substrate/tokens/primitives/src/lib.rs
+++ b/substrate/tokens/primitives/src/lib.rs
@ -0,0 +1,33 @@
+#![cfg_attr(docsrs, feature(doc_cfg))]
+#![cfg_attr(docsrs, feature(doc_auto_cfg))]
+#![cfg_attr(not(feature = "std"), no_std)]
+
+use scale::{Encode, Decode, MaxEncodedLen};
+use scale_info::TypeInfo;
+
+#[cfg(feature = "std")]
+use serde::{Serialize, Deserialize};
+
+use serai_primitives::{SeraiAddress, ExternalAddress, Data, pallet_address};
+
+pub const ADDRESS: SeraiAddress = pallet_address(b"Tokens");
+
+#[derive(Clone, PartialEq, Eq, Debug, Encode, Decode, MaxEncodedLen, TypeInfo)]
+#[cfg_attr(feature = "std", derive(Serialize, Deserialize))]
+pub struct OutInstruction {
+  pub address: ExternalAddress,
+  pub data: Option<Data>,
+}
+
+#[derive(Clone, PartialEq, Eq, Debug, Encode, Decode, MaxEncodedLen, TypeInfo)]
+#[cfg_attr(feature = "std", derive(Serialize, Deserialize))]
+pub enum Destination {
+  Native(SeraiAddress),
+  External(OutInstruction),
+}
+
+#[test]
+fn address() {
+  use sp_runtime::traits::TrailingZeroInput;
+  assert_eq!(ADDRESS, SeraiAddress::decode(&mut TrailingZeroInput::new(b"Tokens")).unwrap());
+}