---
tags: hard_fork_1
---

# Altair(HF1) Official Tracking

## ⭐ Beacon Chain
### New objects in Altair format
#### Protobuf definitions EthereumAPI
- [ ] Beacon block body (type: Altair)
- [ ] Beacon state v1 (type: Altair)
- [ ] Sync aggregate
- [ ] Sync committee

#### Protobuf definitions Eth2API
- [ ] Beacon block body v1 (type: Altair)
- [ ] Beacon state v1 (type: Altair)
- [ ] Sync aggregate
- [ ] Sync committee

#### Custom type
- [ ] Go-bitfield: Bitvector[SYNC_COMMITTEE_SIZE]
- [ ] Eth2-type: ParticipationFlags

### New beacon state pkg for Altair
- [ ] Revamp beacon state phase0 pkg in anticipation of v1
- [ ] Implement beacon state v1 pkg

### Core processing pkgs
- [ ] Sync committees to support light clients
- [ ] New accounting reform
- [ ] Attestation rewards to increase incentive compatibility
- [ ] Per validator inactivity leak
- [ ] Penalty parameter updates toward maximally punitive parameters

### DB pkg
- [ ] Signed beacon block v1 (type: Altair)
- [ ] Beacon state v1 (type: Altair)
### Cache pkg
- [ ] Signed beacon block v1 (type: Altair)
- [ ] Beacon state v1 (type: Altair)
### Networking
- [ ] Gossip blocks to have a higher slot than their parent
- [ ] Beacon block gossip topic for new Altair type
- [ ] Gossip topics and validations for sync committee messages
- [ ] Path for Req/Resp domain to handle cross-fork types

### RPC
- [ ] Validator sync committee assignments
- [ ] Sync committee aggregates in beacon blocks
- [ ] Block proposal for Altair

### Fork logic
- [ ] Switch over Phase 0 beacon state to an Altair beacon state

### Weak subjectivity
- [ ] New weak subjectivity period calculations and sample values

## ⭐ Validator
- [ ] Sync committee aggregates in beacon blocks
- [ ] Validator sync committee assignments
- [ ] Fork awareness

## ⭐ Testing
- [ ] Altair spec tests
- [ ] E2E tests to cover the switch over in various hard fork combinations

## ⭐ References
### Spec
`v1.1.0-alpha.1` is the first Altair pre-release
https://github.com/ethereum/eth2.0-specs/releases/tag/v1.1.0-alpha.1
### Explaners
https://bisontrails.co/eth2/012/