Cairo-lang

**Starknet**
* Performance optimizations in the gateway, the computation of the Patricia storage root and block hash
* Support `secp256r1` syscalls in the Starknet OS. Thanks to Braavos for adapting the `secp256k1` code to `secp256r1`!
* Restriction for `__validate__` and the constructor of `DeployAccount` transactions:
* Restrict access to `sequencer_address` in the `get_execution_info` syscall - return zero values
* Restrict access to some syscalls:
* Cairo contracts: `get_block_hash`
* CairoZero contracts: `get_sequencer_address`

**CairoZero**
* Move structs that are common to `secp256k1` and `secp256r1` to a separate file

**Starknet**
* Performance optimizations in the gateway and the computation of the Patricia storage root
* Support `secp256r1` syscalls in the Starknet OS. Thanks to Braavos for adapting the `secp256k1` code to `secp256r1`!
* Restriction for `__validate__` and the constructor of `DeployAccount` transactions:
* Restrict access to `block_number`, `block_timestamp` and `sequencer_address` in the `get_execution_info` syscall - return zero values
* Restrict access to some syscalls:
* Cairo contracts: `get_block_hash`
* CairoZero contracts: `get_block_number`, `get_block_timestamp`, `get_sequencer_address`

**CairoZero**
* Move structs that are common to `secp256k1` and `secp256r1` to a separate file

**Starknet**

* Add sequencer signature on block hash and state diff, using the following API (see [here](https://community.starknet.io/t/introducing-p2p-authentication-and-mismatch-resolution-in-v0-12-2/97993)):
* `get_signature` - returns the signature on the data
* `get_public_key` - returns the public key used to sign blocks
* Increase the maximum number of steps in a single transaction from 1M to 3M
* Add `0x` prefix in the API responses for state roots
* Add an optional parameter to `get_state_update` API - `includeBlock` which adds block information to the response (see [here](https://community.starknet.io/t/introducing-p2p-authentication-and-mismatch-resolution-in-v0-12-2/97993#combined-state-diff-and-block-endpoint-4))
* An improvement to the max throughput

**Starknet**

* Add sequencer signature on block hash and state diff, using the following API (see [here](https://community.starknet.io/t/introducing-p2p-authentication-and-mismatch-resolution-in-v0-12-2/97993)):
* `get_signature` - returns the signature on the data
* `get_public_key` - returns the public key used to sign blocks
* Increase the maximum number of steps in a single transaction from 1M to 3M
* Add `0x` prefix in the API responses for state roots
* Add an optional parameter to `get_state_update` API - `includeBlock` which adds block information to the response (see [here](https://community.starknet.io/t/introducing-p2p-authentication-and-mismatch-resolution-in-v0-12-2/97993#combined-state-diff-and-block-endpoint-4))
* An improvement to the max throughput

**Starknet**
* Take fee for reverted transactions. At this phase, the Starknet OS doesn't prove that the transactions failed. This will change once the move to Sierra is complete
* Early rejection of transactions that (1) do not pass `validate` (2) have an old nonce or (3) do not pay enough fee
* See [here](https://community.starknet.io/t/efficient-utilization-of-sequencer-capacity-in-starknet-v0-12-1/95607) for more information
* Support of `keccak` and `Secp256k1`
* Fixed a bug where transactions that changed the ETH balance of a user were charged twice for it (once because of reducing the fee and once because of the transaction itself)

**Starknet**
* Take fee for reverted transactions. At this phase, the Starknet OS doesn't prove that the transactions failed. This will change once the move to Sierra is complete
* Early rejection of transactions that (1) do not pass `validate` (2) have an old nonce or (3) do not pay enough fee
* See [here](https://community.starknet.io/t/efficient-utilization-of-sequencer-capacity-in-starknet-v0-12-1/95607) for more information
* Support of keccak and Secp256k1
* Fixed a bug where transactions that changed the ETH balance of a user were charged twice for it (once because of reducing the fee and once because of the transaction itself)