Move Shared/Params Into Config/Params (#9642)

* config params into pkg * gaz Co-authored-by: prylabs-bulldozer[bot] <58059840+prylabs-bulldozer[bot]@users.noreply.github.com>
2026-01-09 21:38:05 -05:00 · 2021-09-21 14:59:25 -05:00
parent 26893bcb8c
commit f3d6dbcc1e
547 changed files with 589 additions and 589 deletions
--- a/config/features/BUILD.bazel
+++ b/config/features/BUILD.bazel
@@ -11,7 +11,7 @@ go_library(
    importpath = "github.com/prysmaticlabs/prysm/config/features",
    visibility = ["//visibility:public"],
    deps = [
-        "//shared/params:go_default_library",
+        "//config/params:go_default_library",
        "@com_github_sirupsen_logrus//:go_default_library",
        "@com_github_urfave_cli_v2//:go_default_library",
    ],
--- a/config/features/config.go
+++ b/config/features/config.go
@@ -23,7 +23,7 @@ import (
 	"sync"
 	"time"

-	"github.com/prysmaticlabs/prysm/shared/params"
+	"github.com/prysmaticlabs/prysm/config/params"
 	"github.com/sirupsen/logrus"
 	"github.com/urfave/cli/v2"
 )
--- a/config/params/BUILD.bazel
+++ b/config/params/BUILD.bazel
@@ -0,0 +1,59 @@
+load("@prysm//tools/go:def.bzl", "go_library", "go_test")
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "config.go",
+        "config_utils_develop.go",  # keep
+        "config_utils_prod.go",
+        "io_config.go",
+        "loader.go",
+        "mainnet_config.go",
+        "minimal_config.go",
+        "network_config.go",
+        "testnet_e2e_config.go",
+        "testnet_prater_config.go",
+        "testnet_pyrmont_config.go",
+        "testutils.go",
+        "values.go",
+    ],
+    importpath = "github.com/prysmaticlabs/prysm/config/params",
+    visibility = ["//visibility:public"],
+    deps = [
+        "//math:go_default_library",
+        "//shared/bytesutil:go_default_library",
+        "@com_github_ethereum_go_ethereum//params:go_default_library",
+        "@com_github_mohae_deepcopy//:go_default_library",
+        "@com_github_prysmaticlabs_eth2_types//:go_default_library",
+        "@com_github_sirupsen_logrus//:go_default_library",
+        "@in_gopkg_yaml_v2//:go_default_library",
+    ],
+)
+
+go_test(
+    name = "go_default_test",
+    size = "small",
+    srcs = [
+        "checktags_test.go",
+        "config_test.go",
+        "loader_test.go",
+        "testnet_config_test.go",
+        "testnet_prater_config_test.go",
+    ],
+    data = glob(["*.yaml"]) + [
+        "@consensus_spec//:spec_data",
+        "@consensus_spec_tests_mainnet//:test_data",
+        "@consensus_spec_tests_minimal//:test_data",
+        "@eth2_networks//:configs",
+    ],
+    gotags = ["develop"],
+    race = "on",
+    deps = [
+        ":go_default_library",
+        "//shared/testutil/assert:go_default_library",
+        "//shared/testutil/require:go_default_library",
+        "@com_github_sirupsen_logrus//:go_default_library",
+        "@in_gopkg_yaml_v2//:go_default_library",
+        "@io_bazel_rules_go//go/tools/bazel:go_default_library",
+    ],
+)
--- a/config/params/checktags_test.go
+++ b/config/params/checktags_test.go
@@ -0,0 +1,11 @@
+// +build !develop
+
+package params_test
+
+import (
+	log "github.com/sirupsen/logrus"
+)
+
+func init() {
+	log.Fatal("Tests in this package require extra build tag: re-run with `-tags develop`")
+}
--- a/config/params/config.go
+++ b/config/params/config.go
@@ -0,0 +1,185 @@
+// Package params defines important constants that are essential to Prysm services.
+package params
+
+import (
+	"time"
+
+	types "github.com/prysmaticlabs/eth2-types"
+	"github.com/prysmaticlabs/prysm/shared/bytesutil"
+)
+
+// BeaconChainConfig contains constant configs for node to participate in beacon chain.
+type BeaconChainConfig struct {
+	// Constants (non-configurable)
+	GenesisSlot              types.Slot  `yaml:"GENESIS_SLOT"`                // GenesisSlot represents the first canonical slot number of the beacon chain.
+	GenesisEpoch             types.Epoch `yaml:"GENESIS_EPOCH"`               // GenesisEpoch represents the first canonical epoch number of the beacon chain.
+	FarFutureEpoch           types.Epoch `yaml:"FAR_FUTURE_EPOCH"`            // FarFutureEpoch represents a epoch extremely far away in the future used as the default penalization epoch for validators.
+	FarFutureSlot            types.Slot  `yaml:"FAR_FUTURE_SLOT"`             // FarFutureSlot represents a slot extremely far away in the future.
+	BaseRewardsPerEpoch      uint64      `yaml:"BASE_REWARDS_PER_EPOCH"`      // BaseRewardsPerEpoch is used to calculate the per epoch rewards.
+	DepositContractTreeDepth uint64      `yaml:"DEPOSIT_CONTRACT_TREE_DEPTH"` // DepositContractTreeDepth depth of the Merkle trie of deposits in the validator deposit contract on the PoW chain.
+	JustificationBitsLength  uint64      `yaml:"JUSTIFICATION_BITS_LENGTH"`   // JustificationBitsLength defines number of epochs to track when implementing k-finality in Casper FFG.
+
+	// Misc constants.
+	PresetBase                     string `yaml:"PRESET_BASE" spec:"true"`                        // PresetBase represents the underlying spec preset this config is based on.
+	ConfigName                     string `yaml:"CONFIG_NAME" spec:"true"`                        // ConfigName for allowing an easy human-readable way of knowing what chain is being used.
+	TargetCommitteeSize            uint64 `yaml:"TARGET_COMMITTEE_SIZE" spec:"true"`              // TargetCommitteeSize is the number of validators in a committee when the chain is healthy.
+	MaxValidatorsPerCommittee      uint64 `yaml:"MAX_VALIDATORS_PER_COMMITTEE" spec:"true"`       // MaxValidatorsPerCommittee defines the upper bound of the size of a committee.
+	MaxCommitteesPerSlot           uint64 `yaml:"MAX_COMMITTEES_PER_SLOT" spec:"true"`            // MaxCommitteesPerSlot defines the max amount of committee in a single slot.
+	MinPerEpochChurnLimit          uint64 `yaml:"MIN_PER_EPOCH_CHURN_LIMIT" spec:"true"`          // MinPerEpochChurnLimit is the minimum amount of churn allotted for validator rotations.
+	ChurnLimitQuotient             uint64 `yaml:"CHURN_LIMIT_QUOTIENT" spec:"true"`               // ChurnLimitQuotient is used to determine the limit of how many validators can rotate per epoch.
+	ShuffleRoundCount              uint64 `yaml:"SHUFFLE_ROUND_COUNT" spec:"true"`                // ShuffleRoundCount is used for retrieving the permuted index.
+	MinGenesisActiveValidatorCount uint64 `yaml:"MIN_GENESIS_ACTIVE_VALIDATOR_COUNT" spec:"true"` // MinGenesisActiveValidatorCount defines how many validator deposits needed to kick off beacon chain.
+	MinGenesisTime                 uint64 `yaml:"MIN_GENESIS_TIME" spec:"true"`                   // MinGenesisTime is the time that needed to pass before kicking off beacon chain.
+	TargetAggregatorsPerCommittee  uint64 `yaml:"TARGET_AGGREGATORS_PER_COMMITTEE" spec:"true"`   // TargetAggregatorsPerCommittee defines the number of aggregators inside one committee.
+	HysteresisQuotient             uint64 `yaml:"HYSTERESIS_QUOTIENT" spec:"true"`                // HysteresisQuotient defines the hysteresis quotient for effective balance calculations.
+	HysteresisDownwardMultiplier   uint64 `yaml:"HYSTERESIS_DOWNWARD_MULTIPLIER" spec:"true"`     // HysteresisDownwardMultiplier defines the hysteresis downward multiplier for effective balance calculations.
+	HysteresisUpwardMultiplier     uint64 `yaml:"HYSTERESIS_UPWARD_MULTIPLIER" spec:"true"`       // HysteresisUpwardMultiplier defines the hysteresis upward multiplier for effective balance calculations.
+
+	// Gwei value constants.
+	MinDepositAmount          uint64 `yaml:"MIN_DEPOSIT_AMOUNT" spec:"true"`          // MinDepositAmount is the minimum amount of Gwei a validator can send to the deposit contract at once (lower amounts will be reverted).
+	MaxEffectiveBalance       uint64 `yaml:"MAX_EFFECTIVE_BALANCE" spec:"true"`       // MaxEffectiveBalance is the maximal amount of Gwei that is effective for staking.
+	EjectionBalance           uint64 `yaml:"EJECTION_BALANCE" spec:"true"`            // EjectionBalance is the minimal GWei a validator needs to have before ejected.
+	EffectiveBalanceIncrement uint64 `yaml:"EFFECTIVE_BALANCE_INCREMENT" spec:"true"` // EffectiveBalanceIncrement is used for converting the high balance into the low balance for validators.
+
+	// Initial value constants.
+	BLSWithdrawalPrefixByte byte     `yaml:"BLS_WITHDRAWAL_PREFIX" spec:"true"` // BLSWithdrawalPrefixByte is used for BLS withdrawal and it's the first byte.
+	ZeroHash                [32]byte // ZeroHash is used to represent a zeroed out 32 byte array.
+
+	// Time parameters constants.
+	GenesisDelay                     uint64      `yaml:"GENESIS_DELAY" spec:"true"`                   // GenesisDelay is the minimum number of seconds to delay starting the Ethereum Beacon Chain genesis. Must be at least 1 second.
+	MinAttestationInclusionDelay     types.Slot  `yaml:"MIN_ATTESTATION_INCLUSION_DELAY" spec:"true"` // MinAttestationInclusionDelay defines how many slots validator has to wait to include attestation for beacon block.
+	SecondsPerSlot                   uint64      `yaml:"SECONDS_PER_SLOT" spec:"true"`                // SecondsPerSlot is how many seconds are in a single slot.
+	SlotsPerEpoch                    types.Slot  `yaml:"SLOTS_PER_EPOCH" spec:"true"`                 // SlotsPerEpoch is the number of slots in an epoch.
+	SqrRootSlotsPerEpoch             types.Slot  // SqrRootSlotsPerEpoch is a hard coded value where we take the square root of `SlotsPerEpoch` and round down.
+	MinSeedLookahead                 types.Epoch `yaml:"MIN_SEED_LOOKAHEAD" spec:"true"`                  // MinSeedLookahead is the duration of randao look ahead seed.
+	MaxSeedLookahead                 types.Epoch `yaml:"MAX_SEED_LOOKAHEAD" spec:"true"`                  // MaxSeedLookahead is the duration a validator has to wait for entry and exit in epoch.
+	EpochsPerEth1VotingPeriod        types.Epoch `yaml:"EPOCHS_PER_ETH1_VOTING_PERIOD" spec:"true"`       // EpochsPerEth1VotingPeriod defines how often the merkle root of deposit receipts get updated in beacon node on per epoch basis.
+	SlotsPerHistoricalRoot           types.Slot  `yaml:"SLOTS_PER_HISTORICAL_ROOT" spec:"true"`           // SlotsPerHistoricalRoot defines how often the historical root is saved.
+	MinValidatorWithdrawabilityDelay types.Epoch `yaml:"MIN_VALIDATOR_WITHDRAWABILITY_DELAY" spec:"true"` // MinValidatorWithdrawabilityDelay is the shortest amount of time a validator has to wait to withdraw.
+	ShardCommitteePeriod             types.Epoch `yaml:"SHARD_COMMITTEE_PERIOD" spec:"true"`              // ShardCommitteePeriod is the minimum amount of epochs a validator must participate before exiting.
+	MinEpochsToInactivityPenalty     types.Epoch `yaml:"MIN_EPOCHS_TO_INACTIVITY_PENALTY" spec:"true"`    // MinEpochsToInactivityPenalty defines the minimum amount of epochs since finality to begin penalizing inactivity.
+	Eth1FollowDistance               uint64      `yaml:"ETH1_FOLLOW_DISTANCE" spec:"true"`                // Eth1FollowDistance is the number of eth1.0 blocks to wait before considering a new deposit for voting. This only applies after the chain as been started.
+	SafeSlotsToUpdateJustified       types.Slot  `yaml:"SAFE_SLOTS_TO_UPDATE_JUSTIFIED" spec:"true"`      // SafeSlotsToUpdateJustified is the minimal slots needed to update justified check point.
+	SecondsPerETH1Block              uint64      `yaml:"SECONDS_PER_ETH1_BLOCK" spec:"true"`              // SecondsPerETH1Block is the approximate time for a single eth1 block to be produced.
+
+	// Ethereum PoW parameters.
+	DepositChainID         uint64 `yaml:"DEPOSIT_CHAIN_ID" spec:"true"`         // DepositChainID of the eth1 network. This used for replay protection.
+	DepositNetworkID       uint64 `yaml:"DEPOSIT_NETWORK_ID" spec:"true"`       // DepositNetworkID of the eth1 network. This used for replay protection.
+	DepositContractAddress string `yaml:"DEPOSIT_CONTRACT_ADDRESS" spec:"true"` // DepositContractAddress is the address of the deposit contract.
+
+	// Validator parameters.
+	RandomSubnetsPerValidator         uint64 `yaml:"RANDOM_SUBNETS_PER_VALIDATOR" spec:"true"`          // RandomSubnetsPerValidator specifies the amount of subnets a validator has to be subscribed to at one time.
+	EpochsPerRandomSubnetSubscription uint64 `yaml:"EPOCHS_PER_RANDOM_SUBNET_SUBSCRIPTION" spec:"true"` // EpochsPerRandomSubnetSubscription specifies the minimum duration a validator is connected to their subnet.
+
+	// State list lengths
+	EpochsPerHistoricalVector types.Epoch `yaml:"EPOCHS_PER_HISTORICAL_VECTOR" spec:"true"` // EpochsPerHistoricalVector defines max length in epoch to store old historical stats in beacon state.
+	EpochsPerSlashingsVector  types.Epoch `yaml:"EPOCHS_PER_SLASHINGS_VECTOR" spec:"true"`  // EpochsPerSlashingsVector defines max length in epoch to store old stats to recompute slashing witness.
+	HistoricalRootsLimit      uint64      `yaml:"HISTORICAL_ROOTS_LIMIT" spec:"true"`       // HistoricalRootsLimit defines max historical roots that can be saved in state before roll over.
+	ValidatorRegistryLimit    uint64      `yaml:"VALIDATOR_REGISTRY_LIMIT" spec:"true"`     // ValidatorRegistryLimit defines the upper bound of validators can participate in eth2.
+
+	// Reward and penalty quotients constants.
+	BaseRewardFactor               uint64 `yaml:"BASE_REWARD_FACTOR" spec:"true"`               // BaseRewardFactor is used to calculate validator per-slot interest rate.
+	WhistleBlowerRewardQuotient    uint64 `yaml:"WHISTLEBLOWER_REWARD_QUOTIENT" spec:"true"`    // WhistleBlowerRewardQuotient is used to calculate whistle blower reward.
+	ProposerRewardQuotient         uint64 `yaml:"PROPOSER_REWARD_QUOTIENT" spec:"true"`         // ProposerRewardQuotient is used to calculate the reward for proposers.
+	InactivityPenaltyQuotient      uint64 `yaml:"INACTIVITY_PENALTY_QUOTIENT" spec:"true"`      // InactivityPenaltyQuotient is used to calculate the penalty for a validator that is offline.
+	MinSlashingPenaltyQuotient     uint64 `yaml:"MIN_SLASHING_PENALTY_QUOTIENT" spec:"true"`    // MinSlashingPenaltyQuotient is used to calculate the minimum penalty to prevent DoS attacks.
+	ProportionalSlashingMultiplier uint64 `yaml:"PROPORTIONAL_SLASHING_MULTIPLIER" spec:"true"` // ProportionalSlashingMultiplier is used as a multiplier on slashed penalties.
+
+	// Max operations per block constants.
+	MaxProposerSlashings uint64 `yaml:"MAX_PROPOSER_SLASHINGS" spec:"true"` // MaxProposerSlashings defines the maximum number of slashings of proposers possible in a block.
+	MaxAttesterSlashings uint64 `yaml:"MAX_ATTESTER_SLASHINGS" spec:"true"` // MaxAttesterSlashings defines the maximum number of casper FFG slashings possible in a block.
+	MaxAttestations      uint64 `yaml:"MAX_ATTESTATIONS" spec:"true"`       // MaxAttestations defines the maximum allowed attestations in a beacon block.
+	MaxDeposits          uint64 `yaml:"MAX_DEPOSITS" spec:"true"`           // MaxDeposits defines the maximum number of validator deposits in a block.
+	MaxVoluntaryExits    uint64 `yaml:"MAX_VOLUNTARY_EXITS" spec:"true"`    // MaxVoluntaryExits defines the maximum number of validator exits in a block.
+
+	// BLS domain values.
+	DomainBeaconProposer              [4]byte `yaml:"DOMAIN_BEACON_PROPOSER" spec:"true"`                // DomainBeaconProposer defines the BLS signature domain for beacon proposal verification.
+	DomainRandao                      [4]byte `yaml:"DOMAIN_RANDAO" spec:"true"`                         // DomainRandao defines the BLS signature domain for randao verification.
+	DomainBeaconAttester              [4]byte `yaml:"DOMAIN_BEACON_ATTESTER" spec:"true"`                // DomainBeaconAttester defines the BLS signature domain for attestation verification.
+	DomainDeposit                     [4]byte `yaml:"DOMAIN_DEPOSIT" spec:"true"`                        // DomainDeposit defines the BLS signature domain for deposit verification.
+	DomainVoluntaryExit               [4]byte `yaml:"DOMAIN_VOLUNTARY_EXIT" spec:"true"`                 // DomainVoluntaryExit defines the BLS signature domain for exit verification.
+	DomainSelectionProof              [4]byte `yaml:"DOMAIN_SELECTION_PROOF" spec:"true"`                // DomainSelectionProof defines the BLS signature domain for selection proof.
+	DomainAggregateAndProof           [4]byte `yaml:"DOMAIN_AGGREGATE_AND_PROOF" spec:"true"`            // DomainAggregateAndProof defines the BLS signature domain for aggregate and proof.
+	DomainSyncCommittee               [4]byte `yaml:"DOMAIN_SYNC_COMMITTEE" spec:"true"`                 // DomainVoluntaryExit defines the BLS signature domain for sync committee.
+	DomainSyncCommitteeSelectionProof [4]byte `yaml:"DOMAIN_SYNC_COMMITTEE_SELECTION_PROOF" spec:"true"` // DomainSelectionProof defines the BLS signature domain for sync committee selection proof.
+	DomainContributionAndProof        [4]byte `yaml:"DOMAIN_CONTRIBUTION_AND_PROOF" spec:"true"`         // DomainAggregateAndProof defines the BLS signature domain for contribution and proof.
+
+	// Prysm constants.
+	GweiPerEth                  uint64        // GweiPerEth is the amount of gwei corresponding to 1 eth.
+	BLSSecretKeyLength          int           // BLSSecretKeyLength defines the expected length of BLS secret keys in bytes.
+	BLSPubkeyLength             int           // BLSPubkeyLength defines the expected length of BLS public keys in bytes.
+	BLSSignatureLength          int           // BLSSignatureLength defines the expected length of BLS signatures in bytes.
+	DefaultBufferSize           int           // DefaultBufferSize for channels across the Prysm repository.
+	ValidatorPrivkeyFileName    string        // ValidatorPrivKeyFileName specifies the string name of a validator private key file.
+	WithdrawalPrivkeyFileName   string        // WithdrawalPrivKeyFileName specifies the string name of a withdrawal private key file.
+	RPCSyncCheck                time.Duration // Number of seconds to query the sync service, to find out if the node is synced or not.
+	EmptySignature              [96]byte      // EmptySignature is used to represent a zeroed out BLS Signature.
+	DefaultPageSize             int           // DefaultPageSize defines the default page size for RPC server request.
+	MaxPeersToSync              int           // MaxPeersToSync describes the limit for number of peers in round robin sync.
+	SlotsPerArchivedPoint       types.Slot    // SlotsPerArchivedPoint defines the number of slots per one archived point.
+	GenesisCountdownInterval    time.Duration // How often to log the countdown until the genesis time is reached.
+	BeaconStateFieldCount       int           // BeaconStateFieldCount defines how many fields are in beacon state.
+	BeaconStateAltairFieldCount int           // BeaconStateAltairFieldCount defines how many fields are in beacon state hard fork 1.
+
+	// Slasher constants.
+	WeakSubjectivityPeriod    types.Epoch // WeakSubjectivityPeriod defines the time period expressed in number of epochs were proof of stake network should validate block headers and attestations for slashable events.
+	PruneSlasherStoragePeriod types.Epoch // PruneSlasherStoragePeriod defines the time period expressed in number of epochs were proof of stake network should prune attestation and block header store.
+
+	// Slashing protection constants.
+	SlashingProtectionPruningEpochs types.Epoch // SlashingProtectionPruningEpochs defines a period after which all prior epochs are pruned in the validator database.
+
+	// Fork-related values.
+	GenesisForkVersion          []byte                  `yaml:"GENESIS_FORK_VERSION" spec:"true"`  // GenesisForkVersion is used to track fork version between state transitions.
+	AltairForkVersion           []byte                  `yaml:"ALTAIR_FORK_VERSION" spec:"true"`   // AltairForkVersion is used to represent the fork version for altair.
+	AltairForkEpoch             types.Epoch             `yaml:"ALTAIR_FORK_EPOCH" spec:"true"`     // AltairForkEpoch is used to represent the assigned fork epoch for altair.
+	MergeForkVersion            []byte                  `yaml:"MERGE_FORK_VERSION" spec:"true"`    // MergeForkVersion is used to represent the fork version for the merge.
+	MergeForkEpoch              types.Epoch             `yaml:"MERGE_FORK_EPOCH" spec:"true"`      // MergeForkEpoch is used to represent the assigned fork epoch for the merge.
+	ShardingForkVersion         []byte                  `yaml:"SHARDING_FORK_VERSION" spec:"true"` // ShardingForkVersion is used to represent the fork version for sharding.
+	ShardingForkEpoch           types.Epoch             `yaml:"SHARDING_FORK_EPOCH" spec:"true"`   // ShardingForkEpoch is used to represent the assigned fork epoch for sharding.
+	ForkVersionSchedule         map[[4]byte]types.Epoch // Schedule of fork epochs by version.
+	MinAnchorPowBlockDifficulty uint64                  `yaml:"MIN_ANCHOR_POW_BLOCK_DIFFICULTY" spec:"true"` // MinAnchorPowBlockDifficulty specifies the target chain difficulty at the time of the merge.
+	TransitionTotalDifficulty   uint64                  `yaml:"TRANSITION_TOTAL_DIFFICULTY" spec:"true"`     // TransitionTotalDifficulty is part of the experimental merge spec. This value is not used (yet) and is expected to be a uint256.
+
+	// Weak subjectivity values.
+	SafetyDecay uint64 // SafetyDecay is defined as the loss in the 1/3 consensus safety margin of the casper FFG mechanism.
+
+	// New values introduced in Altair hard fork 1.
+	// Participation flag indices.
+	TimelySourceFlagIndex uint8 `yaml:"TIMELY_SOURCE_FLAG_INDEX" spec:"true"` // TimelySourceFlagIndex is the source flag position of the participation bits.
+	TimelyTargetFlagIndex uint8 `yaml:"TIMELY_TARGET_FLAG_INDEX" spec:"true"` // TimelyTargetFlagIndex is the target flag position of the participation bits.
+	TimelyHeadFlagIndex   uint8 `yaml:"TIMELY_HEAD_FLAG_INDEX" spec:"true"`   // TimelyHeadFlagIndex is the head flag position of the participation bits.
+
+	// Incentivization weights.
+	TimelySourceWeight uint64 `yaml:"TIMELY_SOURCE_WEIGHT" spec:"true"` // TimelySourceWeight is the factor of how much source rewards receives.
+	TimelyTargetWeight uint64 `yaml:"TIMELY_TARGET_WEIGHT" spec:"true"` // TimelyTargetWeight is the factor of how much target rewards receives.
+	TimelyHeadWeight   uint64 `yaml:"TIMELY_HEAD_WEIGHT" spec:"true"`   // TimelyHeadWeight is the factor of how much head rewards receives.
+	SyncRewardWeight   uint64 `yaml:"SYNC_REWARD_WEIGHT" spec:"true"`   // SyncRewardWeight is the factor of how much sync committee rewards receives.
+	WeightDenominator  uint64 `yaml:"WEIGHT_DENOMINATOR" spec:"true"`   // WeightDenominator accounts for total rewards denomination.
+	ProposerWeight     uint64 `yaml:"PROPOSER_WEIGHT" spec:"true"`      // ProposerWeight is the factor of how much proposer rewards receives.
+
+	// Validator related.
+	TargetAggregatorsPerSyncSubcommittee uint64 `yaml:"TARGET_AGGREGATORS_PER_SYNC_SUBCOMMITTEE" spec:"true"` // TargetAggregatorsPerSyncSubcommittee for aggregating in sync committee.
+	SyncCommitteeSubnetCount             uint64 `yaml:"SYNC_COMMITTEE_SUBNET_COUNT" spec:"true"`              // SyncCommitteeSubnetCount for sync committee subnet count.
+
+	// Misc.
+	SyncCommitteeSize            uint64      `yaml:"SYNC_COMMITTEE_SIZE" spec:"true"`              // SyncCommitteeSize for light client sync committee size.
+	InactivityScoreBias          uint64      `yaml:"INACTIVITY_SCORE_BIAS" spec:"true"`            // InactivityScoreBias for calculating score bias penalties during inactivity
+	InactivityScoreRecoveryRate  uint64      `yaml:"INACTIVITY_SCORE_RECOVERY_RATE" spec:"true"`   // InactivityScoreRecoveryRate for recovering score bias penalties during inactivity.
+	EpochsPerSyncCommitteePeriod types.Epoch `yaml:"EPOCHS_PER_SYNC_COMMITTEE_PERIOD" spec:"true"` // EpochsPerSyncCommitteePeriod defines how many epochs per sync committee period.
+
+	// Updated penalty values. This moves penalty parameters toward their final, maximum security values.
+	// Note: We do not override previous configuration values but instead creates new values and replaces usage throughout.
+	InactivityPenaltyQuotientAltair      uint64 `yaml:"INACTIVITY_PENALTY_QUOTIENT_ALTAIR" spec:"true"`      // InactivityPenaltyQuotientAltair for penalties during inactivity post Altair hard fork.
+	MinSlashingPenaltyQuotientAltair     uint64 `yaml:"MIN_SLASHING_PENALTY_QUOTIENT_ALTAIR" spec:"true"`    // MinSlashingPenaltyQuotientAltair for slashing penalties post Altair hard fork.
+	ProportionalSlashingMultiplierAltair uint64 `yaml:"PROPORTIONAL_SLASHING_MULTIPLIER_ALTAIR" spec:"true"` // ProportionalSlashingMultiplierAltair for slashing penalties multiplier post Alair hard fork.
+}
+
+// InitializeForkSchedule initializes the schedules forks baked into the config.
+func (b *BeaconChainConfig) InitializeForkSchedule() {
+	// Reset Fork Version Schedule.
+	b.ForkVersionSchedule = map[[4]byte]types.Epoch{}
+	// Set Genesis fork data.
+	b.ForkVersionSchedule[bytesutil.ToBytes4(b.GenesisForkVersion)] = b.GenesisEpoch
+	// Set Altair fork data.
+	b.ForkVersionSchedule[bytesutil.ToBytes4(b.AltairForkVersion)] = b.AltairForkEpoch
+}
--- a/config/params/config_test.go
+++ b/config/params/config_test.go
@@ -0,0 +1,46 @@
+package params_test
+
+import (
+	"testing"
+
+	"github.com/prysmaticlabs/prysm/config/params"
+)
+
+// Test cases can be executed in an arbitrary order. TestOverrideBeaconConfigTestTeardown checks
+// that there's no state mutation leak from the previous test, therefore we need a sentinel flag,
+// to make sure that previous test case has already been completed and check can be run.
+var testOverrideBeaconConfigExecuted bool
+
+func TestConfig_OverrideBeaconConfig(t *testing.T) {
+	// Ensure that param modifications are safe.
+	params.SetupTestConfigCleanup(t)
+	cfg := params.BeaconConfig()
+	cfg.SlotsPerEpoch = 5
+	params.OverrideBeaconConfig(cfg)
+	if c := params.BeaconConfig(); c.SlotsPerEpoch != 5 {
+		t.Errorf("Shardcount in BeaconConfig incorrect. Wanted %d, got %d", 5, c.SlotsPerEpoch)
+	}
+	testOverrideBeaconConfigExecuted = true
+}
+
+func TestConfig_OverrideBeaconConfigTestTeardown(t *testing.T) {
+	if !testOverrideBeaconConfigExecuted {
+		t.Skip("State leak can occur only if state mutating test has already completed")
+	}
+	cfg := params.BeaconConfig()
+	if cfg.SlotsPerEpoch == 5 {
+		t.Fatal("Parameter update has been leaked out of previous test")
+	}
+}
+
+func TestConfig_DataRace(t *testing.T) {
+	for i := 0; i < 10; i++ {
+		go func() {
+			cfg := params.BeaconConfig()
+			params.OverrideBeaconConfig(cfg)
+		}()
+		go func() uint64 {
+			return params.BeaconConfig().MaxDeposits
+		}()
+	}
+}
--- a/config/params/config_utils_develop.go
+++ b/config/params/config_utils_develop.go
@@ -0,0 +1,40 @@
+// +build develop
+
+package params
+
+import (
+	"sync"
+
+	"github.com/mohae/deepcopy"
+)
+
+var beaconConfig = MainnetConfig()
+var beaconConfigLock sync.RWMutex
+
+// BeaconConfig retrieves beacon chain config.
+func BeaconConfig() *BeaconChainConfig {
+	beaconConfigLock.RLock()
+	defer beaconConfigLock.RUnlock()
+	return beaconConfig
+}
+
+// OverrideBeaconConfig by replacing the config. The preferred pattern is to
+// call BeaconConfig(), change the specific parameters, and then call
+// OverrideBeaconConfig(c). Any subsequent calls to params.BeaconConfig() will
+// return this new configuration.
+func OverrideBeaconConfig(c *BeaconChainConfig) {
+	beaconConfigLock.Lock()
+	defer beaconConfigLock.Unlock()
+	beaconConfig = c
+}
+
+// Copy returns a copy of the config object.
+func (c *BeaconChainConfig) Copy() *BeaconChainConfig {
+	beaconConfigLock.RLock()
+	defer beaconConfigLock.RUnlock()
+	config, ok := deepcopy.Copy(*c).(BeaconChainConfig)
+	if !ok {
+		config = *beaconConfig
+	}
+	return &config
+}
--- a/config/params/config_utils_prod.go
+++ b/config/params/config_utils_prod.go
@@ -0,0 +1,31 @@
+// +build !develop
+
+package params
+
+import (
+	"github.com/mohae/deepcopy"
+)
+
+var beaconConfig = MainnetConfig()
+
+// BeaconConfig retrieves beacon chain config.
+func BeaconConfig() *BeaconChainConfig {
+	return beaconConfig
+}
+
+// OverrideBeaconConfig by replacing the config. The preferred pattern is to
+// call BeaconConfig(), change the specific parameters, and then call
+// OverrideBeaconConfig(c). Any subsequent calls to params.BeaconConfig() will
+// return this new configuration.
+func OverrideBeaconConfig(c *BeaconChainConfig) {
+	beaconConfig = c
+}
+
+// Copy returns a copy of the config object.
+func (c *BeaconChainConfig) Copy() *BeaconChainConfig {
+	config, ok := deepcopy.Copy(*c).(BeaconChainConfig)
+	if !ok {
+		config = *beaconConfig
+	}
+	return &config
+}
--- a/config/params/io_config.go
+++ b/config/params/io_config.go
@@ -0,0 +1,35 @@
+package params
+
+import (
+	"os"
+	"runtime"
+	"time"
+)
+
+// IoConfig defines the shared io parameters.
+type IoConfig struct {
+	ReadWritePermissions        os.FileMode
+	ReadWriteExecutePermissions os.FileMode
+	BoltTimeout                 time.Duration
+}
+
+var defaultIoConfig = &IoConfig{
+	ReadWritePermissions:        0600,            //-rw------- Read and Write permissions for user
+	ReadWriteExecutePermissions: 0700,            //-rwx------ Read Write and Execute (traverse) permissions for user
+	BoltTimeout:                 1 * time.Second, // 1 second for the bolt DB to timeout.
+}
+
+var defaultWindowsIoConfig = &IoConfig{
+	ReadWritePermissions:        0666,
+	ReadWriteExecutePermissions: 0777,
+	BoltTimeout:                 1 * time.Second,
+}
+
+// BeaconIoConfig returns the current io config for
+// the beacon chain.
+func BeaconIoConfig() *IoConfig {
+	if runtime.GOOS == "windows" {
+		return defaultWindowsIoConfig
+	}
+	return defaultIoConfig
+}
--- a/config/params/loader.go
+++ b/config/params/loader.go
@@ -0,0 +1,136 @@
+package params
+
+import (
+	"encoding/hex"
+	"io/ioutil"
+	"strings"
+
+	types "github.com/prysmaticlabs/eth2-types"
+	"github.com/prysmaticlabs/prysm/math"
+	log "github.com/sirupsen/logrus"
+	"gopkg.in/yaml.v2"
+)
+
+// LoadChainConfigFile load, convert hex values into valid param yaml format,
+// unmarshal , and apply beacon chain config file.
+func LoadChainConfigFile(chainConfigFileName string) {
+	yamlFile, err := ioutil.ReadFile(chainConfigFileName) // #nosec G304
+	if err != nil {
+		log.WithError(err).Fatal("Failed to read chain config file.")
+	}
+	// Default to using mainnet.
+	conf := MainnetConfig().Copy()
+	// Convert 0x hex inputs to fixed bytes arrays
+	lines := strings.Split(string(yamlFile), "\n")
+	for i, line := range lines {
+		// No need to convert the deposit contract address to byte array (as config expects a string).
+		if strings.HasPrefix(line, "DEPOSIT_CONTRACT_ADDRESS") {
+			continue
+		}
+		if strings.HasPrefix(line, "PRESET_BASE: 'minimal'") || strings.HasPrefix(line, "# Minimal preset") {
+			conf = MinimalSpecConfig().Copy()
+		}
+
+		if !strings.HasPrefix(line, "#") && strings.Contains(line, "0x") {
+			parts := ReplaceHexStringWithYAMLFormat(line)
+			lines[i] = strings.Join(parts, "\n")
+		}
+	}
+	yamlFile = []byte(strings.Join(lines, "\n"))
+	if err := yaml.UnmarshalStrict(yamlFile, conf); err != nil {
+		if _, ok := err.(*yaml.TypeError); !ok {
+			log.WithError(err).Fatal("Failed to parse chain config yaml file.")
+		} else {
+			log.WithError(err).Error("There were some issues parsing the config from a yaml file")
+		}
+	}
+	// recompute SqrRootSlotsPerEpoch constant to handle non-standard values of SlotsPerEpoch
+	conf.SqrRootSlotsPerEpoch = types.Slot(math.IntegerSquareRoot(uint64(conf.SlotsPerEpoch)))
+	log.Debugf("Config file values: %+v", conf)
+	OverrideBeaconConfig(conf)
+}
+
+// ReplaceHexStringWithYAMLFormat will replace hex strings that the yaml parser will understand.
+func ReplaceHexStringWithYAMLFormat(line string) []string {
+	parts := strings.Split(line, "0x")
+	decoded, err := hex.DecodeString(parts[1])
+	if err != nil {
+		log.WithError(err).Error("Failed to decode hex string.")
+	}
+	switch l := len(decoded); {
+	case l == 1:
+		var b byte
+		b = decoded[0]
+		fixedByte, err := yaml.Marshal(b)
+		if err != nil {
+			log.WithError(err).Error("Failed to marshal config file.")
+		}
+		parts[0] += string(fixedByte)
+		parts = parts[:1]
+	case l > 1 && l <= 4:
+		var arr [4]byte
+		copy(arr[:], decoded)
+		fixedByte, err := yaml.Marshal(arr)
+		if err != nil {
+			log.WithError(err).Error("Failed to marshal config file.")
+		}
+		parts[1] = string(fixedByte)
+	case l > 4 && l <= 8:
+		var arr [8]byte
+		copy(arr[:], decoded)
+		fixedByte, err := yaml.Marshal(arr)
+		if err != nil {
+			log.WithError(err).Error("Failed to marshal config file.")
+		}
+		parts[1] = string(fixedByte)
+	case l > 8 && l <= 16:
+		var arr [16]byte
+		copy(arr[:], decoded)
+		fixedByte, err := yaml.Marshal(arr)
+		if err != nil {
+			log.WithError(err).Error("Failed to marshal config file.")
+		}
+		parts[1] = string(fixedByte)
+	case l > 16 && l <= 20:
+		var arr [20]byte
+		copy(arr[:], decoded)
+		fixedByte, err := yaml.Marshal(arr)
+		if err != nil {
+			log.WithError(err).Error("Failed to marshal config file.")
+		}
+		parts[1] = string(fixedByte)
+	case l > 20 && l <= 32:
+		var arr [32]byte
+		copy(arr[:], decoded)
+		fixedByte, err := yaml.Marshal(arr)
+		if err != nil {
+			log.WithError(err).Error("Failed to marshal config file.")
+		}
+		parts[1] = string(fixedByte)
+	case l > 32 && l <= 48:
+		var arr [48]byte
+		copy(arr[:], decoded)
+		fixedByte, err := yaml.Marshal(arr)
+		if err != nil {
+			log.WithError(err).Error("Failed to marshal config file.")
+		}
+		parts[1] = string(fixedByte)
+	case l > 48 && l <= 64:
+		var arr [64]byte
+		copy(arr[:], decoded)
+		fixedByte, err := yaml.Marshal(arr)
+		if err != nil {
+			log.WithError(err).Error("Failed to marshal config file.")
+		}
+		parts[1] = string(fixedByte)
+	case l > 64 && l <= 96:
+		var arr [96]byte
+		copy(arr[:], decoded)
+		fixedByte, err := yaml.Marshal(arr)
+		if err != nil {
+			log.WithError(err).Error("Failed to marshal config file.")
+		}
+		parts[1] = string(fixedByte)
+	}
+	return parts
+}
--- a/config/params/loader_test.go
+++ b/config/params/loader_test.go
@@ -0,0 +1,270 @@
+package params_test
+
+import (
+	"io/ioutil"
+	"path"
+	"reflect"
+	"strings"
+	"testing"
+
+	"github.com/bazelbuild/rules_go/go/tools/bazel"
+	"github.com/prysmaticlabs/prysm/config/params"
+	"github.com/prysmaticlabs/prysm/shared/testutil/assert"
+	"github.com/prysmaticlabs/prysm/shared/testutil/require"
+	"gopkg.in/yaml.v2"
+)
+
+func TestLoadConfigFileMainnet(t *testing.T) {
+	// See https://media.githubusercontent.com/media/ethereum/consensus-spec-tests/master/tests/minimal/config/phase0.yaml
+	assertVals := func(name string, fields []string, c1, c2 *params.BeaconChainConfig) {
+		//  Misc params.
+		assert.Equal(t, c1.MaxCommitteesPerSlot, c2.MaxCommitteesPerSlot, "%s: MaxCommitteesPerSlot", name)
+		assert.Equal(t, c1.TargetCommitteeSize, c2.TargetCommitteeSize, "%s: TargetCommitteeSize", name)
+		assert.Equal(t, c1.MaxValidatorsPerCommittee, c2.MaxValidatorsPerCommittee, "%s: MaxValidatorsPerCommittee", name)
+		assert.Equal(t, c1.MinPerEpochChurnLimit, c2.MinPerEpochChurnLimit, "%s: MinPerEpochChurnLimit", name)
+		assert.Equal(t, c1.ChurnLimitQuotient, c2.ChurnLimitQuotient, "%s: ChurnLimitQuotient", name)
+		assert.Equal(t, c1.ShuffleRoundCount, c2.ShuffleRoundCount, "%s: ShuffleRoundCount", name)
+		assert.Equal(t, c1.MinGenesisActiveValidatorCount, c2.MinGenesisActiveValidatorCount, "%s: MinGenesisActiveValidatorCount", name)
+		assert.Equal(t, c1.MinGenesisTime, c2.MinGenesisTime, "%s: MinGenesisTime", name)
+		assert.Equal(t, c1.HysteresisQuotient, c2.HysteresisQuotient, "%s: HysteresisQuotient", name)
+		assert.Equal(t, c1.HysteresisDownwardMultiplier, c2.HysteresisDownwardMultiplier, "%s: HysteresisDownwardMultiplier", name)
+		assert.Equal(t, c1.HysteresisUpwardMultiplier, c2.HysteresisUpwardMultiplier, "%s: HysteresisUpwardMultiplier", name)
+
+		// Fork Choice params.
+		assert.Equal(t, c1.SafeSlotsToUpdateJustified, c2.SafeSlotsToUpdateJustified, "%s: SafeSlotsToUpdateJustified", name)
+
+		// Validator params.
+		assert.Equal(t, c1.Eth1FollowDistance, c2.Eth1FollowDistance, "%s: Eth1FollowDistance", name)
+		assert.Equal(t, c1.TargetAggregatorsPerCommittee, c2.TargetAggregatorsPerCommittee, "%s: TargetAggregatorsPerCommittee", name)
+		assert.Equal(t, c1.RandomSubnetsPerValidator, c2.RandomSubnetsPerValidator, "%s: RandomSubnetsPerValidator", name)
+		assert.Equal(t, c1.EpochsPerRandomSubnetSubscription, c2.EpochsPerRandomSubnetSubscription, "%s: EpochsPerRandomSubnetSubscription", name)
+		assert.Equal(t, c1.SecondsPerETH1Block, c2.SecondsPerETH1Block, "%s: SecondsPerETH1Block", name)
+
+		// Deposit contract.
+		assert.Equal(t, c1.DepositChainID, c2.DepositChainID, "%s: DepositChainID", name)
+		assert.Equal(t, c1.DepositNetworkID, c2.DepositNetworkID, "%s: DepositNetworkID", name)
+		assert.Equal(t, c1.DepositContractAddress, c2.DepositContractAddress, "%s: DepositContractAddress", name)
+
+		// Gwei values.
+		assert.Equal(t, c1.MinDepositAmount, c2.MinDepositAmount, "%s: MinDepositAmount", name)
+		assert.Equal(t, c1.MaxEffectiveBalance, c2.MaxEffectiveBalance, "%s: MaxEffectiveBalance", name)
+		assert.Equal(t, c1.EjectionBalance, c2.EjectionBalance, "%s: EjectionBalance", name)
+		assert.Equal(t, c1.EffectiveBalanceIncrement, c2.EffectiveBalanceIncrement, "%s: EffectiveBalanceIncrement", name)
+
+		// Initial values.
+		assert.DeepEqual(t, c1.GenesisForkVersion, c2.GenesisForkVersion, "%s: GenesisForkVersion", name)
+		assert.DeepEqual(t, c1.BLSWithdrawalPrefixByte, c2.BLSWithdrawalPrefixByte, "%s: BLSWithdrawalPrefixByte", name)
+
+		// Time parameters.
+		assert.Equal(t, c1.GenesisDelay, c2.GenesisDelay, "%s: GenesisDelay", name)
+		assert.Equal(t, c1.SecondsPerSlot, c2.SecondsPerSlot, "%s: SecondsPerSlot", name)
+		assert.Equal(t, c1.MinAttestationInclusionDelay, c2.MinAttestationInclusionDelay, "%s: MinAttestationInclusionDelay", name)
+		assert.Equal(t, c1.SlotsPerEpoch, c2.SlotsPerEpoch, "%s: SlotsPerEpoch", name)
+		assert.Equal(t, c1.MinSeedLookahead, c2.MinSeedLookahead, "%s: MinSeedLookahead", name)
+		assert.Equal(t, c1.MaxSeedLookahead, c2.MaxSeedLookahead, "%s: MaxSeedLookahead", name)
+		assert.Equal(t, c1.EpochsPerEth1VotingPeriod, c2.EpochsPerEth1VotingPeriod, "%s: EpochsPerEth1VotingPeriod", name)
+		assert.Equal(t, c1.SlotsPerHistoricalRoot, c2.SlotsPerHistoricalRoot, "%s: SlotsPerHistoricalRoot", name)
+		assert.Equal(t, c1.MinValidatorWithdrawabilityDelay, c2.MinValidatorWithdrawabilityDelay, "%s: MinValidatorWithdrawabilityDelay", name)
+		assert.Equal(t, c1.ShardCommitteePeriod, c2.ShardCommitteePeriod, "%s: ShardCommitteePeriod", name)
+		assert.Equal(t, c1.MinEpochsToInactivityPenalty, c2.MinEpochsToInactivityPenalty, "%s: MinEpochsToInactivityPenalty", name)
+
+		// State vector lengths.
+		assert.Equal(t, c1.EpochsPerHistoricalVector, c2.EpochsPerHistoricalVector, "%s: EpochsPerHistoricalVector", name)
+		assert.Equal(t, c1.EpochsPerSlashingsVector, c2.EpochsPerSlashingsVector, "%s: EpochsPerSlashingsVector", name)
+		assert.Equal(t, c1.HistoricalRootsLimit, c2.HistoricalRootsLimit, "%s: HistoricalRootsLimit", name)
+		assert.Equal(t, c1.ValidatorRegistryLimit, c2.ValidatorRegistryLimit, "%s: ValidatorRegistryLimit", name)
+
+		// Reward and penalty quotients.
+		assert.Equal(t, c1.BaseRewardFactor, c2.BaseRewardFactor, "%s: BaseRewardFactor", name)
+		assert.Equal(t, c1.WhistleBlowerRewardQuotient, c2.WhistleBlowerRewardQuotient, "%s: WhistleBlowerRewardQuotient", name)
+		assert.Equal(t, c1.ProposerRewardQuotient, c2.ProposerRewardQuotient, "%s: ProposerRewardQuotient", name)
+		assert.Equal(t, c1.InactivityPenaltyQuotient, c2.InactivityPenaltyQuotient, "%s: InactivityPenaltyQuotient", name)
+		assert.Equal(t, c1.InactivityPenaltyQuotientAltair, c2.InactivityPenaltyQuotientAltair, "%s: InactivityPenaltyQuotientAltair", name)
+		assert.Equal(t, c1.MinSlashingPenaltyQuotient, c2.MinSlashingPenaltyQuotient, "%s: MinSlashingPenaltyQuotient", name)
+		assert.Equal(t, c1.MinSlashingPenaltyQuotientAltair, c2.MinSlashingPenaltyQuotientAltair, "%s: MinSlashingPenaltyQuotientAltair", name)
+		assert.Equal(t, c1.ProportionalSlashingMultiplier, c2.ProportionalSlashingMultiplier, "%s: ProportionalSlashingMultiplier", name)
+		assert.Equal(t, c1.ProportionalSlashingMultiplierAltair, c2.ProportionalSlashingMultiplierAltair, "%s: ProportionalSlashingMultiplierAltair", name)
+
+		// Max operations per block.
+		assert.Equal(t, c1.MaxProposerSlashings, c2.MaxProposerSlashings, "%s: MaxProposerSlashings", name)
+		assert.Equal(t, c1.MaxAttesterSlashings, c2.MaxAttesterSlashings, "%s: MaxAttesterSlashings", name)
+		assert.Equal(t, c1.MaxAttestations, c2.MaxAttestations, "%s: MaxAttestations", name)
+		assert.Equal(t, c1.MaxDeposits, c2.MaxDeposits, "%s: MaxDeposits", name)
+		assert.Equal(t, c1.MaxVoluntaryExits, c2.MaxVoluntaryExits, "%s: MaxVoluntaryExits", name)
+
+		// Signature domains.
+		assert.Equal(t, c1.DomainBeaconProposer, c2.DomainBeaconProposer, "%s: DomainBeaconProposer", name)
+		assert.Equal(t, c1.DomainBeaconAttester, c2.DomainBeaconAttester, "%s: DomainBeaconAttester", name)
+		assert.Equal(t, c1.DomainRandao, c2.DomainRandao, "%s: DomainRandao", name)
+		assert.Equal(t, c1.DomainDeposit, c2.DomainDeposit, "%s: DomainDeposit", name)
+		assert.Equal(t, c1.DomainVoluntaryExit, c2.DomainVoluntaryExit, "%s: DomainVoluntaryExit", name)
+		assert.Equal(t, c1.DomainSelectionProof, c2.DomainSelectionProof, "%s: DomainSelectionProof", name)
+		assert.Equal(t, c1.DomainAggregateAndProof, c2.DomainAggregateAndProof, "%s: DomainAggregateAndProof", name)
+
+		assertYamlFieldsMatch(t, name, fields, c1, c2)
+	}
+
+	t.Run("mainnet", func(t *testing.T) {
+		mainnetConfigFile := presetsFilePath(t, "mainnet")
+		params.LoadChainConfigFile(mainnetConfigFile)
+		fields := fieldsFromYaml(t, mainnetConfigFile)
+		assertVals("mainnet", fields, params.MainnetConfig(), params.BeaconConfig())
+	})
+
+	t.Run("minimal", func(t *testing.T) {
+		minimalConfigFile := presetsFilePath(t, "minimal")
+		params.LoadChainConfigFile(minimalConfigFile)
+		fields := fieldsFromYaml(t, minimalConfigFile)
+		assertVals("minimal", fields, params.MinimalSpecConfig(), params.BeaconConfig())
+	})
+}
+
+func TestLoadConfigFile_OverwriteCorrectly(t *testing.T) {
+	file, err := ioutil.TempFile("", "")
+	require.NoError(t, err)
+	// Set current config to minimal config
+	params.OverrideBeaconConfig(params.MinimalSpecConfig())
+
+	// load empty config file, so that it defaults to mainnet values
+	params.LoadChainConfigFile(file.Name())
+	if params.BeaconConfig().MinGenesisTime != params.MainnetConfig().MinGenesisTime {
+		t.Errorf("Expected MinGenesisTime to be set to mainnet value: %d found: %d",
+			params.MainnetConfig().MinGenesisTime,
+			params.BeaconConfig().MinGenesisTime)
+	}
+	if params.BeaconConfig().SlotsPerEpoch != params.MainnetConfig().SlotsPerEpoch {
+		t.Errorf("Expected SlotsPerEpoch to be set to mainnet value: %d found: %d",
+			params.MainnetConfig().SlotsPerEpoch,
+			params.BeaconConfig().SlotsPerEpoch)
+	}
+}
+
+func Test_replaceHexStringWithYAMLFormat(t *testing.T) {
+
+	testLines := []struct {
+		line   string
+		wanted string
+	}{
+		{
+			line:   "ONE_BYTE: 0x41",
+			wanted: "ONE_BYTE: 65\n",
+		},
+		{
+			line:   "FOUR_BYTES: 0x41414141",
+			wanted: "FOUR_BYTES: \n- 65\n- 65\n- 65\n- 65\n",
+		},
+		{
+			line:   "THREE_BYTES: 0x414141",
+			wanted: "THREE_BYTES: \n- 65\n- 65\n- 65\n- 0\n",
+		},
+		{
+			line:   "EIGHT_BYTES: 0x4141414141414141",
+			wanted: "EIGHT_BYTES: \n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n",
+		},
+		{
+			line: "SIXTEEN_BYTES: 0x41414141414141414141414141414141",
+			wanted: "SIXTEEN_BYTES: \n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n" +
+				"- 65\n- 65\n- 65\n- 65\n",
+		},
+		{
+			line: "TWENTY_BYTES: 0x4141414141414141414141414141414141414141",
+			wanted: "TWENTY_BYTES: \n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n" +
+				"- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n",
+		},
+		{
+			line: "THIRTY_TWO_BYTES: 0x4141414141414141414141414141414141414141414141414141414141414141",
+			wanted: "THIRTY_TWO_BYTES: \n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n" +
+				"- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n" +
+				"- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n",
+		},
+		{
+			line: "FORTY_EIGHT_BYTES: 0x41414141414141414141414141414141414141414141414141414141414141414141" +
+				"4141414141414141414141414141",
+			wanted: "FORTY_EIGHT_BYTES: \n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n" +
+				"- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n" +
+				"- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n" +
+				"- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n",
+		},
+		{
+			line: "NINETY_SIX_BYTES: 0x414141414141414141414141414141414141414141414141414141414141414141414141" +
+				"4141414141414141414141414141414141414141414141414141414141414141414141414141414141414141414141" +
+				"41414141414141414141414141",
+			wanted: "NINETY_SIX_BYTES: \n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n" +
+				"- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n" +
+				"- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n" +
+				"- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n" +
+				"- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n" +
+				"- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n" +
+				"- 65\n- 65\n- 65\n- 65\n- 65\n- 65\n",
+		},
+	}
+	for _, line := range testLines {
+		parts := params.ReplaceHexStringWithYAMLFormat(line.line)
+		res := strings.Join(parts, "\n")
+
+		if res != line.wanted {
+			t.Errorf("expected conversion to be: %v got: %v", line.wanted, res)
+		}
+	}
+}
+
+// configFilePath sets the proper config and returns the relevant
+// config file path from eth2-spec-tests directory.
+func configFilePath(t *testing.T, config string) string {
+	filepath, err := bazel.Runfile("external/consensus_spec")
+	require.NoError(t, err)
+	configFilePath := path.Join(filepath, "configs", config+".yaml")
+	return configFilePath
+}
+
+// presetsFilePath sets the proper preset and returns the relevant
+// preset file path from eth2-spec-tests directory.
+func presetsFilePath(t *testing.T, config string) string {
+	filepath, err := bazel.Runfile("external/consensus_spec")
+	require.NoError(t, err)
+	configFilePath := path.Join(filepath, "presets", config, "phase0.yaml")
+	return configFilePath
+}
+
+func fieldsFromYaml(t *testing.T, fp string) []string {
+	yamlFile, err := ioutil.ReadFile(fp)
+	require.NoError(t, err)
+	m := make(map[string]interface{})
+	require.NoError(t, yaml.Unmarshal(yamlFile, &m))
+
+	var keys []string
+	for k := range m {
+		keys = append(keys, k)
+	}
+
+	if len(keys) == 0 {
+		t.Errorf("No fields loaded from yaml file %s", fp)
+	}
+
+	return keys
+}
+
+func assertYamlFieldsMatch(t *testing.T, name string, fields []string, c1, c2 *params.BeaconChainConfig) {
+	// Ensure all fields from the yaml file exist, were set, and correctly match the expected value.
+	ft1 := reflect.TypeOf(*c1)
+	for _, field := range fields {
+		var found bool
+		for i := 0; i < ft1.NumField(); i++ {
+			v, ok := ft1.Field(i).Tag.Lookup("yaml")
+			if ok && v == field {
+				found = true
+				v1 := reflect.ValueOf(*c1).Field(i).Interface()
+				v2 := reflect.ValueOf(*c2).Field(i).Interface()
+				if reflect.ValueOf(v1).Kind() == reflect.Slice {
+					assert.DeepEqual(t, v1, v2, "%s: %s", name, field)
+				} else {
+					assert.Equal(t, v1, v2, "%s: %s", name, field)
+				}
+				break
+			}
+		}
+		if !found {
+			t.Errorf("No struct tag found `yaml:%s`", field)
+		}
+	}
+}
--- a/config/params/mainnet_config.go
+++ b/config/params/mainnet_config.go
@@ -0,0 +1,231 @@
+package params
+
+import (
+	"math"
+	"time"
+
+	types "github.com/prysmaticlabs/eth2-types"
+	"github.com/prysmaticlabs/prysm/shared/bytesutil"
+)
+
+// MainnetConfig returns the configuration to be used in the main network.
+func MainnetConfig() *BeaconChainConfig {
+	return mainnetBeaconConfig
+}
+
+// UseMainnetConfig for beacon chain services.
+func UseMainnetConfig() {
+	beaconConfig = MainnetConfig()
+}
+
+const (
+	// Genesis Fork Epoch for the mainnet config.
+	genesisForkEpoch = 0
+	// Altair Fork Epoch for mainnet config.
+	// Placeholder until fork epoch is decided.
+	mainnetAltairForkEpoch = math.MaxUint64
+)
+
+var mainnetNetworkConfig = &NetworkConfig{
+	GossipMaxSize:                   1 << 20, // 1 MiB
+	MaxChunkSize:                    1 << 20, // 1 MiB
+	AttestationSubnetCount:          64,
+	AttestationPropagationSlotRange: 32,
+	MaxRequestBlocks:                1 << 10, // 1024
+	TtfbTimeout:                     5 * time.Second,
+	RespTimeout:                     10 * time.Second,
+	MaximumGossipClockDisparity:     500 * time.Millisecond,
+	MessageDomainInvalidSnappy:      [4]byte{00, 00, 00, 00},
+	MessageDomainValidSnappy:        [4]byte{01, 00, 00, 00},
+	ETH2Key:                         "eth2",
+	AttSubnetKey:                    "attnets",
+	SyncCommsSubnetKey:              "syncnets",
+	MinimumPeersInSubnetSearch:      20,
+	ContractDeploymentBlock:         11184524, // Note: contract was deployed in block 11052984 but no transactions were sent until 11184524.
+	BootstrapNodes: []string{
+		// Teku team's bootnode
+		"enr:-KG4QOtcP9X1FbIMOe17QNMKqDxCpm14jcX5tiOE4_TyMrFqbmhPZHK_ZPG2Gxb1GE2xdtodOfx9-cgvNtxnRyHEmC0ghGV0aDKQ9aX9QgAAAAD__________4JpZIJ2NIJpcIQDE8KdiXNlY3AyNTZrMaEDhpehBDbZjM_L9ek699Y7vhUJ-eAdMyQW_Fil522Y0fODdGNwgiMog3VkcIIjKA",
+		"enr:-KG4QDyytgmE4f7AnvW-ZaUOIi9i79qX4JwjRAiXBZCU65wOfBu-3Nb5I7b_Rmg3KCOcZM_C3y5pg7EBU5XGrcLTduQEhGV0aDKQ9aX9QgAAAAD__________4JpZIJ2NIJpcIQ2_DUbiXNlY3AyNTZrMaEDKnz_-ps3UUOfHWVYaskI5kWYO_vtYMGYCQRAR3gHDouDdGNwgiMog3VkcIIjKA",
+		// Prylab team's bootnodes
+		"enr:-Ku4QImhMc1z8yCiNJ1TyUxdcfNucje3BGwEHzodEZUan8PherEo4sF7pPHPSIB1NNuSg5fZy7qFsjmUKs2ea1Whi0EBh2F0dG5ldHOIAAAAAAAAAACEZXRoMpD1pf1CAAAAAP__________gmlkgnY0gmlwhBLf22SJc2VjcDI1NmsxoQOVphkDqal4QzPMksc5wnpuC3gvSC8AfbFOnZY_On34wIN1ZHCCIyg",
+		"enr:-Ku4QP2xDnEtUXIjzJ_DhlCRN9SN99RYQPJL92TMlSv7U5C1YnYLjwOQHgZIUXw6c-BvRg2Yc2QsZxxoS_pPRVe0yK8Bh2F0dG5ldHOIAAAAAAAAAACEZXRoMpD1pf1CAAAAAP__________gmlkgnY0gmlwhBLf22SJc2VjcDI1NmsxoQMeFF5GrS7UZpAH2Ly84aLK-TyvH-dRo0JM1i8yygH50YN1ZHCCJxA",
+		"enr:-Ku4QPp9z1W4tAO8Ber_NQierYaOStqhDqQdOPY3bB3jDgkjcbk6YrEnVYIiCBbTxuar3CzS528d2iE7TdJsrL-dEKoBh2F0dG5ldHOIAAAAAAAAAACEZXRoMpD1pf1CAAAAAP__________gmlkgnY0gmlwhBLf22SJc2VjcDI1NmsxoQMw5fqqkw2hHC4F5HZZDPsNmPdB1Gi8JPQK7pRc9XHh-oN1ZHCCKvg",
+		// Lighthouse team's bootnodes
+		"enr:-IS4QLkKqDMy_ExrpOEWa59NiClemOnor-krjp4qoeZwIw2QduPC-q7Kz4u1IOWf3DDbdxqQIgC4fejavBOuUPy-HE4BgmlkgnY0gmlwhCLzAHqJc2VjcDI1NmsxoQLQSJfEAHZApkm5edTCZ_4qps_1k_ub2CxHFxi-gr2JMIN1ZHCCIyg",
+		"enr:-IS4QDAyibHCzYZmIYZCjXwU9BqpotWmv2BsFlIq1V31BwDDMJPFEbox1ijT5c2Ou3kvieOKejxuaCqIcjxBjJ_3j_cBgmlkgnY0gmlwhAMaHiCJc2VjcDI1NmsxoQJIdpj_foZ02MXz4It8xKD7yUHTBx7lVFn3oeRP21KRV4N1ZHCCIyg",
+		// EF bootnodes
+		"enr:-Ku4QHqVeJ8PPICcWk1vSn_XcSkjOkNiTg6Fmii5j6vUQgvzMc9L1goFnLKgXqBJspJjIsB91LTOleFmyWWrFVATGngBh2F0dG5ldHOIAAAAAAAAAACEZXRoMpC1MD8qAAAAAP__________gmlkgnY0gmlwhAMRHkWJc2VjcDI1NmsxoQKLVXFOhp2uX6jeT0DvvDpPcU8FWMjQdR4wMuORMhpX24N1ZHCCIyg",
+		"enr:-Ku4QG-2_Md3sZIAUebGYT6g0SMskIml77l6yR-M_JXc-UdNHCmHQeOiMLbylPejyJsdAPsTHJyjJB2sYGDLe0dn8uYBh2F0dG5ldHOIAAAAAAAAAACEZXRoMpC1MD8qAAAAAP__________gmlkgnY0gmlwhBLY-NyJc2VjcDI1NmsxoQORcM6e19T1T9gi7jxEZjk_sjVLGFscUNqAY9obgZaxbIN1ZHCCIyg",
+		"enr:-Ku4QPn5eVhcoF1opaFEvg1b6JNFD2rqVkHQ8HApOKK61OIcIXD127bKWgAtbwI7pnxx6cDyk_nI88TrZKQaGMZj0q0Bh2F0dG5ldHOIAAAAAAAAAACEZXRoMpC1MD8qAAAAAP__________gmlkgnY0gmlwhDayLMaJc2VjcDI1NmsxoQK2sBOLGcUb4AwuYzFuAVCaNHA-dy24UuEKkeFNgCVCsIN1ZHCCIyg",
+		"enr:-Ku4QEWzdnVtXc2Q0ZVigfCGggOVB2Vc1ZCPEc6j21NIFLODSJbvNaef1g4PxhPwl_3kax86YPheFUSLXPRs98vvYsoBh2F0dG5ldHOIAAAAAAAAAACEZXRoMpC1MD8qAAAAAP__________gmlkgnY0gmlwhDZBrP2Jc2VjcDI1NmsxoQM6jr8Rb1ktLEsVcKAPa08wCsKUmvoQ8khiOl_SLozf9IN1ZHCCIyg",
+	},
+}
+
+var mainnetBeaconConfig = &BeaconChainConfig{
+	// Constants (Non-configurable)
+	FarFutureEpoch:           1<<64 - 1,
+	FarFutureSlot:            1<<64 - 1,
+	BaseRewardsPerEpoch:      4,
+	DepositContractTreeDepth: 32,
+	GenesisDelay:             604800, // 1 week.
+
+	// Misc constant.
+	TargetCommitteeSize:            128,
+	MaxValidatorsPerCommittee:      2048,
+	MaxCommitteesPerSlot:           64,
+	MinPerEpochChurnLimit:          4,
+	ChurnLimitQuotient:             1 << 16,
+	ShuffleRoundCount:              90,
+	MinGenesisActiveValidatorCount: 16384,
+	MinGenesisTime:                 1606824000, // Dec 1, 2020, 12pm UTC.
+	TargetAggregatorsPerCommittee:  16,
+	HysteresisQuotient:             4,
+	HysteresisDownwardMultiplier:   1,
+	HysteresisUpwardMultiplier:     5,
+
+	// Gwei value constants.
+	MinDepositAmount:          1 * 1e9,
+	MaxEffectiveBalance:       32 * 1e9,
+	EjectionBalance:           16 * 1e9,
+	EffectiveBalanceIncrement: 1 * 1e9,
+
+	// Initial value constants.
+	BLSWithdrawalPrefixByte: byte(0),
+	ZeroHash:                [32]byte{},
+
+	// Time parameter constants.
+	MinAttestationInclusionDelay:     1,
+	SecondsPerSlot:                   12,
+	SlotsPerEpoch:                    32,
+	SqrRootSlotsPerEpoch:             5,
+	MinSeedLookahead:                 1,
+	MaxSeedLookahead:                 4,
+	EpochsPerEth1VotingPeriod:        64,
+	SlotsPerHistoricalRoot:           8192,
+	MinValidatorWithdrawabilityDelay: 256,
+	ShardCommitteePeriod:             256,
+	MinEpochsToInactivityPenalty:     4,
+	Eth1FollowDistance:               2048,
+	SafeSlotsToUpdateJustified:       8,
+
+	// Ethereum PoW parameters.
+	DepositChainID:         1, // Chain ID of eth1 mainnet.
+	DepositNetworkID:       1, // Network ID of eth1 mainnet.
+	DepositContractAddress: "0x00000000219ab540356cBB839Cbe05303d7705Fa",
+
+	// Validator params.
+	RandomSubnetsPerValidator:         1 << 0,
+	EpochsPerRandomSubnetSubscription: 1 << 8,
+
+	// While eth1 mainnet block times are closer to 13s, we must conform with other clients in
+	// order to vote on the correct eth1 blocks.
+	//
+	// Additional context: https://github.com/ethereum/consensus-specs/issues/2132
+	// Bug prompting this change: https://github.com/prysmaticlabs/prysm/issues/7856
+	// Future optimization: https://github.com/prysmaticlabs/prysm/issues/7739
+	SecondsPerETH1Block: 14,
+
+	// State list length constants.
+	EpochsPerHistoricalVector: 65536,
+	EpochsPerSlashingsVector:  8192,
+	HistoricalRootsLimit:      16777216,
+	ValidatorRegistryLimit:    1099511627776,
+
+	// Reward and penalty quotients constants.
+	BaseRewardFactor:               64,
+	WhistleBlowerRewardQuotient:    512,
+	ProposerRewardQuotient:         8,
+	InactivityPenaltyQuotient:      67108864,
+	MinSlashingPenaltyQuotient:     128,
+	ProportionalSlashingMultiplier: 1,
+
+	// Max operations per block constants.
+	MaxProposerSlashings: 16,
+	MaxAttesterSlashings: 2,
+	MaxAttestations:      128,
+	MaxDeposits:          16,
+	MaxVoluntaryExits:    16,
+
+	// BLS domain values.
+	DomainBeaconProposer:              bytesutil.ToBytes4(bytesutil.Bytes4(0)),
+	DomainBeaconAttester:              bytesutil.ToBytes4(bytesutil.Bytes4(1)),
+	DomainRandao:                      bytesutil.ToBytes4(bytesutil.Bytes4(2)),
+	DomainDeposit:                     bytesutil.ToBytes4(bytesutil.Bytes4(3)),
+	DomainVoluntaryExit:               bytesutil.ToBytes4(bytesutil.Bytes4(4)),
+	DomainSelectionProof:              bytesutil.ToBytes4(bytesutil.Bytes4(5)),
+	DomainAggregateAndProof:           bytesutil.ToBytes4(bytesutil.Bytes4(6)),
+	DomainSyncCommittee:               bytesutil.ToBytes4(bytesutil.Bytes4(7)),
+	DomainSyncCommitteeSelectionProof: bytesutil.ToBytes4(bytesutil.Bytes4(8)),
+	DomainContributionAndProof:        bytesutil.ToBytes4(bytesutil.Bytes4(9)),
+
+	// Prysm constants.
+	GweiPerEth:                  1000000000,
+	BLSSecretKeyLength:          32,
+	BLSPubkeyLength:             48,
+	BLSSignatureLength:          96,
+	DefaultBufferSize:           10000,
+	WithdrawalPrivkeyFileName:   "/shardwithdrawalkey",
+	ValidatorPrivkeyFileName:    "/validatorprivatekey",
+	RPCSyncCheck:                1,
+	EmptySignature:              [96]byte{},
+	DefaultPageSize:             250,
+	MaxPeersToSync:              15,
+	SlotsPerArchivedPoint:       2048,
+	GenesisCountdownInterval:    time.Minute,
+	ConfigName:                  ConfigNames[Mainnet],
+	PresetBase:                  "mainnet",
+	BeaconStateFieldCount:       21,
+	BeaconStateAltairFieldCount: 24,
+
+	// Slasher related values.
+	WeakSubjectivityPeriod:          54000,
+	PruneSlasherStoragePeriod:       10,
+	SlashingProtectionPruningEpochs: 512,
+
+	// Weak subjectivity values.
+	SafetyDecay: 10,
+
+	// Fork related values.
+	GenesisForkVersion:          []byte{0, 0, 0, 0},
+	AltairForkVersion:           []byte{1, 0, 0, 0},
+	AltairForkEpoch:             mainnetAltairForkEpoch,
+	MergeForkVersion:            []byte{2, 0, 0, 0},
+	MergeForkEpoch:              math.MaxUint64,
+	ShardingForkVersion:         []byte{3, 0, 0, 0},
+	ShardingForkEpoch:           math.MaxUint64,
+	MinAnchorPowBlockDifficulty: 4294967296,
+	ForkVersionSchedule: map[[4]byte]types.Epoch{
+		{0, 0, 0, 0}: genesisForkEpoch,
+		{1, 0, 0, 0}: mainnetAltairForkEpoch,
+		// Any further forks must be specified here by their epoch number.
+	},
+
+	// New values introduced in Altair hard fork 1.
+	// Participation flag indices.
+	TimelySourceFlagIndex: 0,
+	TimelyTargetFlagIndex: 1,
+	TimelyHeadFlagIndex:   2,
+
+	// Incentivization weight values.
+	TimelySourceWeight: 14,
+	TimelyTargetWeight: 26,
+	TimelyHeadWeight:   14,
+	SyncRewardWeight:   2,
+	ProposerWeight:     8,
+	WeightDenominator:  64,
+
+	// Validator related values.
+	TargetAggregatorsPerSyncSubcommittee: 16,
+	SyncCommitteeSubnetCount:             4,
+
+	// Misc values.
+	SyncCommitteeSize:            512,
+	InactivityScoreBias:          4,
+	InactivityScoreRecoveryRate:  16,
+	EpochsPerSyncCommitteePeriod: 256,
+
+	// Updated penalty values.
+	InactivityPenaltyQuotientAltair:      3 * 1 << 24, //50331648
+	MinSlashingPenaltyQuotientAltair:     64,
+	ProportionalSlashingMultiplierAltair: 2,
+}
--- a/config/params/minimal_config.go
+++ b/config/params/minimal_config.go
@@ -0,0 +1,113 @@
+package params
+
+import (
+	"math"
+
+	types "github.com/prysmaticlabs/eth2-types"
+	"github.com/prysmaticlabs/prysm/shared/bytesutil"
+)
+
+// UseMinimalConfig for beacon chain services.
+func UseMinimalConfig() {
+	beaconConfig = MinimalSpecConfig()
+}
+
+// MinimalSpecConfig retrieves the minimal config used in spec tests.
+func MinimalSpecConfig() *BeaconChainConfig {
+	minimalConfig := mainnetBeaconConfig.Copy()
+	// Misc
+	minimalConfig.MaxCommitteesPerSlot = 4
+	minimalConfig.TargetCommitteeSize = 4
+	minimalConfig.MaxValidatorsPerCommittee = 2048
+	minimalConfig.MinPerEpochChurnLimit = 4
+	minimalConfig.ChurnLimitQuotient = 32
+	minimalConfig.ShuffleRoundCount = 10
+	minimalConfig.MinGenesisActiveValidatorCount = 64
+	minimalConfig.MinGenesisTime = 1578009600
+	minimalConfig.GenesisDelay = 300 // 5 minutes
+	minimalConfig.TargetAggregatorsPerCommittee = 16
+
+	// Gwei values
+	minimalConfig.MinDepositAmount = 1e9
+	minimalConfig.MaxEffectiveBalance = 32e9
+	minimalConfig.EjectionBalance = 16e9
+	minimalConfig.EffectiveBalanceIncrement = 1e9
+
+	// Initial values
+	minimalConfig.BLSWithdrawalPrefixByte = byte(0)
+
+	// Time parameters
+	minimalConfig.SecondsPerSlot = 6
+	minimalConfig.MinAttestationInclusionDelay = 1
+	minimalConfig.SlotsPerEpoch = 8
+	minimalConfig.SqrRootSlotsPerEpoch = 2
+	minimalConfig.MinSeedLookahead = 1
+	minimalConfig.MaxSeedLookahead = 4
+	minimalConfig.EpochsPerEth1VotingPeriod = 4
+	minimalConfig.SlotsPerHistoricalRoot = 64
+	minimalConfig.MinValidatorWithdrawabilityDelay = 256
+	minimalConfig.ShardCommitteePeriod = 64
+	minimalConfig.MinEpochsToInactivityPenalty = 4
+	minimalConfig.Eth1FollowDistance = 16
+	minimalConfig.SafeSlotsToUpdateJustified = 2
+	minimalConfig.SecondsPerETH1Block = 14
+
+	// State vector lengths
+	minimalConfig.EpochsPerHistoricalVector = 64
+	minimalConfig.EpochsPerSlashingsVector = 64
+	minimalConfig.HistoricalRootsLimit = 16777216
+	minimalConfig.ValidatorRegistryLimit = 1099511627776
+
+	// Reward and penalty quotients
+	minimalConfig.BaseRewardFactor = 64
+	minimalConfig.WhistleBlowerRewardQuotient = 512
+	minimalConfig.ProposerRewardQuotient = 8
+	minimalConfig.InactivityPenaltyQuotient = 33554432
+	minimalConfig.MinSlashingPenaltyQuotient = 64
+	minimalConfig.ProportionalSlashingMultiplier = 2
+
+	// Max operations per block
+	minimalConfig.MaxProposerSlashings = 16
+	minimalConfig.MaxAttesterSlashings = 2
+	minimalConfig.MaxAttestations = 128
+	minimalConfig.MaxDeposits = 16
+	minimalConfig.MaxVoluntaryExits = 16
+
+	// Signature domains
+	minimalConfig.DomainBeaconProposer = bytesutil.ToBytes4(bytesutil.Bytes4(0))
+	minimalConfig.DomainBeaconAttester = bytesutil.ToBytes4(bytesutil.Bytes4(1))
+	minimalConfig.DomainRandao = bytesutil.ToBytes4(bytesutil.Bytes4(2))
+	minimalConfig.DomainDeposit = bytesutil.ToBytes4(bytesutil.Bytes4(3))
+	minimalConfig.DomainVoluntaryExit = bytesutil.ToBytes4(bytesutil.Bytes4(4))
+	minimalConfig.GenesisForkVersion = []byte{0, 0, 0, 1}
+
+	minimalConfig.DepositContractTreeDepth = 32
+	minimalConfig.FarFutureEpoch = 1<<64 - 1
+	minimalConfig.FarFutureSlot = 1<<64 - 1
+
+	// New Altair params
+	minimalConfig.AltairForkVersion = []byte{1, 0, 0, 1} // Highest byte set to 0x01 to avoid collisions with mainnet versioning
+	minimalConfig.AltairForkEpoch = math.MaxUint64
+	minimalConfig.MergeForkVersion = []byte{2, 0, 0, 1}
+	minimalConfig.MergeForkEpoch = math.MaxUint64
+	minimalConfig.ShardingForkVersion = []byte{3, 0, 0, 1}
+	minimalConfig.ShardingForkEpoch = math.MaxUint64
+	// Manually set fork version schedule here.
+	minimalConfig.ForkVersionSchedule = map[[4]byte]types.Epoch{
+		{0, 0, 0, 1}: 0,
+		{1, 0, 0, 1}: math.MaxUint64,
+	}
+	minimalConfig.SyncCommitteeSize = 32
+	minimalConfig.InactivityScoreBias = 4
+	minimalConfig.EpochsPerSyncCommitteePeriod = 8
+
+	// Ethereum PoW parameters.
+	minimalConfig.DepositChainID = 5   // Chain ID of eth1 goerli.
+	minimalConfig.DepositNetworkID = 5 // Network ID of eth1 goerli.
+	minimalConfig.DepositContractAddress = "0x1234567890123456789012345678901234567890"
+
+	minimalConfig.ConfigName = ConfigNames[Minimal]
+	minimalConfig.PresetBase = "minimal"
+
+	return minimalConfig
+}
--- a/config/params/network_config.go
+++ b/config/params/network_config.go
@@ -0,0 +1,55 @@
+package params
+
+import (
+	"time"
+
+	"github.com/mohae/deepcopy"
+	types "github.com/prysmaticlabs/eth2-types"
+)
+
+// NetworkConfig defines the spec based network parameters.
+type NetworkConfig struct {
+	GossipMaxSize                   uint64        `yaml:"GOSSIP_MAX_SIZE"`                    // GossipMaxSize is the maximum allowed size of uncompressed gossip messages.
+	MaxChunkSize                    uint64        `yaml:"MAX_CHUNK_SIZE"`                     // MaxChunkSize is the the maximum allowed size of uncompressed req/resp chunked responses.
+	AttestationSubnetCount          uint64        `yaml:"ATTESTATION_SUBNET_COUNT"`           // AttestationSubnetCount is the number of attestation subnets used in the gossipsub protocol.
+	AttestationPropagationSlotRange types.Slot    `yaml:"ATTESTATION_PROPAGATION_SLOT_RANGE"` // AttestationPropagationSlotRange is the maximum number of slots during which an attestation can be propagated.
+	MaxRequestBlocks                uint64        `yaml:"MAX_REQUEST_BLOCKS"`                 // MaxRequestBlocks is the maximum number of blocks in a single request.
+	TtfbTimeout                     time.Duration `yaml:"TTFB_TIMEOUT"`                       // TtfbTimeout is the maximum time to wait for first byte of request response (time-to-first-byte).
+	RespTimeout                     time.Duration `yaml:"RESP_TIMEOUT"`                       // RespTimeout is the maximum time for complete response transfer.
+	MaximumGossipClockDisparity     time.Duration `yaml:"MAXIMUM_GOSSIP_CLOCK_DISPARITY"`     // MaximumGossipClockDisparity is the maximum milliseconds of clock disparity assumed between honest nodes.
+	MessageDomainInvalidSnappy      [4]byte       `yaml:"MESSAGE_DOMAIN_INVALID_SNAPPY"`      // MessageDomainInvalidSnappy is the 4-byte domain for gossip message-id isolation of invalid snappy messages.
+	MessageDomainValidSnappy        [4]byte       `yaml:"MESSAGE_DOMAIN_VALID_SNAPPY"`        // MessageDomainValidSnappy is the 4-byte domain for gossip message-id isolation of valid snappy messages.
+
+	// DiscoveryV5 Config
+	ETH2Key                    string // ETH2Key is the ENR key of the Ethereum consensus object in an enr.
+	AttSubnetKey               string // AttSubnetKey is the ENR key of the subnet bitfield in the enr.
+	SyncCommsSubnetKey         string // SyncCommsSubnetKey is the ENR key of the sync committee subnet bitfield in the enr.
+	MinimumPeersInSubnetSearch uint64 // PeersInSubnetSearch is the required amount of peers that we need to be able to lookup in a subnet search.
+
+	// Chain Network Config
+	ContractDeploymentBlock uint64   // ContractDeploymentBlock is the eth1 block in which the deposit contract is deployed.
+	BootstrapNodes          []string // BootstrapNodes are the addresses of the bootnodes.
+}
+
+var networkConfig = mainnetNetworkConfig
+
+// BeaconNetworkConfig returns the current network config for
+// the beacon chain.
+func BeaconNetworkConfig() *NetworkConfig {
+	return networkConfig
+}
+
+// OverrideBeaconNetworkConfig will override the network
+// config with the added argument.
+func OverrideBeaconNetworkConfig(cfg *NetworkConfig) {
+	networkConfig = cfg.Copy()
+}
+
+// Copy returns Copy of the config object.
+func (c *NetworkConfig) Copy() *NetworkConfig {
+	config, ok := deepcopy.Copy(*c).(NetworkConfig)
+	if !ok {
+		config = *networkConfig
+	}
+	return &config
+}
--- a/config/params/testnet_config_test.go
+++ b/config/params/testnet_config_test.go
@@ -0,0 +1,16 @@
+package params_test
+
+import (
+	"path"
+	"testing"
+
+	"github.com/bazelbuild/rules_go/go/tools/bazel"
+	"github.com/prysmaticlabs/prysm/shared/testutil/require"
+)
+
+func testnetConfigFilePath(t *testing.T, network string) string {
+	filepath, err := bazel.Runfile("external/eth2_networks")
+	require.NoError(t, err)
+	configFilePath := path.Join(filepath, "shared", network, "config.yaml")
+	return configFilePath
+}
--- a/config/params/testnet_e2e_config.go
+++ b/config/params/testnet_e2e_config.go
@@ -0,0 +1,44 @@
+package params
+
+const AltairE2EForkEpoch = 6
+
+// UseE2EConfig for beacon chain services.
+func UseE2EConfig() {
+	beaconConfig = E2ETestConfig()
+
+	cfg := BeaconNetworkConfig().Copy()
+	OverrideBeaconNetworkConfig(cfg)
+}
+
+// E2ETestConfig retrieves the configurations made specifically for E2E testing.
+// Warning: This config is only for testing, it is not meant for use outside of E2E.
+func E2ETestConfig() *BeaconChainConfig {
+	e2eConfig := MinimalSpecConfig()
+
+	// Misc.
+	e2eConfig.MinGenesisActiveValidatorCount = 256
+	e2eConfig.GenesisDelay = 10 // 10 seconds so E2E has enough time to process deposits and get started.
+	e2eConfig.ChurnLimitQuotient = 65536
+
+	// Time parameters.
+	e2eConfig.SecondsPerSlot = 10
+	e2eConfig.SlotsPerEpoch = 6
+	e2eConfig.SqrRootSlotsPerEpoch = 2
+	e2eConfig.SecondsPerETH1Block = 2
+	e2eConfig.Eth1FollowDistance = 4
+	e2eConfig.EpochsPerEth1VotingPeriod = 2
+	e2eConfig.ShardCommitteePeriod = 4
+	e2eConfig.MaxSeedLookahead = 1
+
+	// PoW parameters.
+	e2eConfig.DepositChainID = 1337   // Chain ID of eth1 dev net.
+	e2eConfig.DepositNetworkID = 1337 // Network ID of eth1 dev net.
+
+	// Altair Fork Parameters.
+	e2eConfig.AltairForkEpoch = AltairE2EForkEpoch
+
+	// Prysm constants.
+	e2eConfig.ConfigName = ConfigNames[EndToEnd]
+
+	return e2eConfig
+}
--- a/config/params/testnet_prater_config.go
+++ b/config/params/testnet_prater_config.go
@@ -0,0 +1,49 @@
+package params
+
+import (
+	eth1Params "github.com/ethereum/go-ethereum/params"
+)
+
+// UsePraterNetworkConfig uses the Prater specific
+// network config.
+func UsePraterNetworkConfig() {
+	cfg := BeaconNetworkConfig().Copy()
+	cfg.ContractDeploymentBlock = 4367322
+	cfg.BootstrapNodes = []string{
+		// Prysm's bootnode
+		"enr:-Ku4QFmUkNp0g9bsLX2PfVeIyT-9WO-PZlrqZBNtEyofOOfLMScDjaTzGxIb1Ns9Wo5Pm_8nlq-SZwcQfTH2cgO-s88Bh2F0dG5ldHOIAAAAAAAAAACEZXRoMpDkvpOTAAAQIP__________gmlkgnY0gmlwhBLf22SJc2VjcDI1NmsxoQLV_jMOIxKbjHFKgrkFvwDvpexo6Nd58TK5k7ss4Vt0IoN1ZHCCG1g",
+		// Lighthouse's bootnode by Afri
+		"enr:-LK4QH1xnjotgXwg25IDPjrqRGFnH1ScgNHA3dv1Z8xHCp4uP3N3Jjl_aYv_WIxQRdwZvSukzbwspXZ7JjpldyeVDzMCh2F0dG5ldHOIAAAAAAAAAACEZXRoMpB53wQoAAAQIP__________gmlkgnY0gmlwhIe1te-Jc2VjcDI1NmsxoQOkcGXqbCJYbcClZ3z5f6NWhX_1YPFRYRRWQpJjwSHpVIN0Y3CCIyiDdWRwgiMo",
+		// Lighthouse's bootnode by Sigp
+		"enr:-LK4QLINdtobGquK7jukLDAKmsrH2ZuHM4k0TklY5jDTD4ZgfxR9weZmo5Jwu81hlKu3qPAvk24xHGBDjYs4o8f1gZ0Bh2F0dG5ldHOIAAAAAAAAAACEZXRoMpB53wQoAAAQIP__________gmlkgnY0gmlwhDRN_P6Jc2VjcDI1NmsxoQJuNujTgsJUHUgVZML3pzrtgNtYg7rQ4K1tkWERgl0DdoN0Y3CCIyiDdWRwgiMo",
+		// Teku's bootnode By Afri
+		"enr:-KG4QCIzJZTY_fs_2vqWEatJL9RrtnPwDCv-jRBuO5FQ2qBrfJubWOWazri6s9HsyZdu-fRUfEzkebhf1nvO42_FVzwDhGV0aDKQed8EKAAAECD__________4JpZIJ2NIJpcISHtbYziXNlY3AyNTZrMaED4m9AqVs6F32rSCGsjtYcsyfQE2K8nDiGmocUY_iq-TSDdGNwgiMog3VkcIIjKA",
+	}
+	OverrideBeaconNetworkConfig(cfg)
+}
+
+// UsePraterConfig sets the main beacon chain
+// config for Prater.
+func UsePraterConfig() {
+	beaconConfig = PraterConfig()
+}
+
+// PraterConfig defines the config for the
+// Prater testnet.
+func PraterConfig() *BeaconChainConfig {
+	cfg := MainnetConfig().Copy()
+	cfg.MinGenesisTime = 1614588812
+	cfg.GenesisDelay = 1919188
+	cfg.ConfigName = ConfigNames[Prater]
+	cfg.GenesisForkVersion = []byte{0x00, 0x00, 0x10, 0x20}
+	cfg.SecondsPerETH1Block = 14
+	cfg.DepositChainID = eth1Params.GoerliChainConfig.ChainID.Uint64()
+	cfg.DepositNetworkID = eth1Params.GoerliChainConfig.ChainID.Uint64()
+	cfg.AltairForkEpoch = 36660
+	cfg.AltairForkVersion = []byte{0x1, 0x0, 0x10, 0x20}
+	cfg.ShardingForkVersion = []byte{0x3, 0x0, 0x10, 0x20}
+	cfg.MergeForkVersion = []byte{0x2, 0x0, 0x10, 0x20}
+	cfg.TransitionTotalDifficulty = 4294967296
+	cfg.DepositContractAddress = "0xff50ed3d0ec03aC01D4C79aAd74928BFF48a7b2b"
+	return cfg
+}
--- a/config/params/testnet_prater_config_test.go
+++ b/config/params/testnet_prater_config_test.go
@@ -0,0 +1,14 @@
+package params_test
+
+import (
+	"testing"
+
+	"github.com/prysmaticlabs/prysm/config/params"
+)
+
+func TestPraterConfigMatchesUpstreamYaml(t *testing.T) {
+	configFP := testnetConfigFilePath(t, "prater")
+	params.LoadChainConfigFile(configFP)
+	fields := fieldsFromYaml(t, configFP)
+	assertYamlFieldsMatch(t, "prater", fields, params.BeaconConfig(), params.PraterConfig())
+}
--- a/config/params/testnet_pyrmont_config.go
+++ b/config/params/testnet_pyrmont_config.go
@@ -0,0 +1,42 @@
+package params
+
+import "math"
+
+// UsePyrmontNetworkConfig uses the Pyrmont specific
+// network config.
+func UsePyrmontNetworkConfig() {
+	cfg := BeaconNetworkConfig().Copy()
+	cfg.ContractDeploymentBlock = 3743587
+	cfg.BootstrapNodes = []string{
+		"enr:-Ku4QOA5OGWObY8ep_x35NlGBEj7IuQULTjkgxC_0G1AszqGEA0Wn2RNlyLFx9zGTNB1gdFBA6ZDYxCgIza1uJUUOj4Dh2F0dG5ldHOIAAAAAAAAAACEZXRoMpDVTPWXAAAgCf__________gmlkgnY0gmlwhDQPSjiJc2VjcDI1NmsxoQM6yTQB6XGWYJbI7NZFBjp4Yb9AYKQPBhVrfUclQUobb4N1ZHCCIyg",
+		"enr:-Ku4QOksdA2tabOGrfOOr6NynThMoio6Ggka2oDPqUuFeWCqcRM2alNb8778O_5bK95p3EFt0cngTUXm2H7o1jkSJ_8Dh2F0dG5ldHOIAAAAAAAAAACEZXRoMpDVTPWXAAAgCf__________gmlkgnY0gmlwhDaa13aJc2VjcDI1NmsxoQKdNQJvnohpf0VO0ZYCAJxGjT0uwJoAHbAiBMujGjK0SoN1ZHCCIyg",
+	}
+	OverrideBeaconNetworkConfig(cfg)
+}
+
+// UsePyrmontConfig sets the main beacon chain
+// config for Pyrmont.
+func UsePyrmontConfig() {
+	beaconConfig = PyrmontConfig()
+}
+
+// PyrmontConfig defines the config for the
+// Pyrmont testnet.
+func PyrmontConfig() *BeaconChainConfig {
+	cfg := MainnetConfig().Copy()
+	cfg.MinGenesisTime = 1605700800
+	cfg.GenesisDelay = 432000
+	cfg.ConfigName = ConfigNames[Pyrmont]
+	cfg.GenesisForkVersion = []byte{0x00, 0x00, 0x20, 0x09}
+	cfg.AltairForkVersion = []byte{0x01, 0x00, 0x20, 0x09}
+	cfg.AltairForkEpoch = 61650
+	cfg.MergeForkVersion = []byte{0x02, 0x00, 0x20, 0x09}
+	cfg.MergeForkEpoch = math.MaxUint64
+	cfg.ShardingForkVersion = []byte{0x03, 0x00, 0x20, 0x09}
+	cfg.ShardingForkEpoch = math.MaxUint64
+	cfg.SecondsPerETH1Block = 14
+	cfg.DepositChainID = 5
+	cfg.DepositNetworkID = 5
+	cfg.DepositContractAddress = "0x8c5fecdC472E27Bc447696F431E425D02dd46a8c"
+	return cfg
+}
--- a/config/params/testutils.go
+++ b/config/params/testutils.go
@@ -0,0 +1,16 @@
+package params
+
+import "testing"
+
+// SetupTestConfigCleanup preserves configurations allowing to modify them within tests without any
+// restrictions, everything is restored after the test.
+func SetupTestConfigCleanup(t testing.TB) {
+	prevDefaultBeaconConfig := mainnetBeaconConfig.Copy()
+	prevBeaconConfig := beaconConfig.Copy()
+	prevNetworkCfg := networkConfig.Copy()
+	t.Cleanup(func() {
+		mainnetBeaconConfig = prevDefaultBeaconConfig
+		beaconConfig = prevBeaconConfig
+		networkConfig = prevNetworkCfg
+	})
+}
--- a/config/params/values.go
+++ b/config/params/values.go
@@ -0,0 +1,21 @@
+package params
+
+const (
+	Mainnet ConfigName = iota
+	Minimal
+	EndToEnd
+	Pyrmont
+	Prater
+)
+
+// ConfigNames provides network configuration names.
+var ConfigNames = map[ConfigName]string{
+	Mainnet:  "mainnet",
+	Minimal:  "minimal",
+	EndToEnd: "end-to-end",
+	Pyrmont:  "pyrmont",
+	Prater:   "prater",
+}
+
+// ConfigName enum describes the type of known network in use.
+type ConfigName = int