diff --git a/crates/node/builder/src/rpc.rs b/crates/node/builder/src/rpc.rs
index 70adcc83d69..ed0a3fb64d4 100644
--- a/crates/node/builder/src/rpc.rs
+++ b/crates/node/builder/src/rpc.rs
@@ -23,8 +23,8 @@ use reth_node_core::{
     version::{version_metadata, CLIENT_CODE},
 };
 use reth_payload_builder::{PayloadBuilderHandle, PayloadStore};
-use reth_rpc::eth::{core::EthRpcConverterFor, EthApiTypes, FullEthApiServer};
-use reth_rpc_api::{eth::helpers::AddDevSigners, IntoEngineApiRpcModule};
+use reth_rpc::eth::{core::EthRpcConverterFor, DevSigner, EthApiTypes, FullEthApiServer};
+use reth_rpc_api::{eth::helpers::EthTransactions, IntoEngineApiRpcModule};
 use reth_rpc_builder::{
     auth::{AuthRpcModule, AuthServerHandle},
     config::RethRpcServerConfig,
@@ -991,7 +991,8 @@ where
 
         // in dev mode we generate 20 random dev-signer accounts
         if config.dev.dev {
-            registry.eth_api().with_dev_accounts();
+            let signers = DevSigner::from_mnemonic(config.dev.dev_mnemonic.as_str(), 20);
+            registry.eth_api().signers().write().extend(signers);
         }
 
         let mut registry = RpcRegistry { registry };
@@ -1163,7 +1164,6 @@ pub trait EthApiBuilder<N: FullNodeComponents>: Default + Send + 'static {
     /// The Ethapi implementation this builder will build.
     type EthApi: EthApiTypes
         + FullEthApiServer<Provider = N::Provider, Pool = N::Pool>
-        + AddDevSigners
         + Unpin
         + 'static;
 
diff --git a/crates/node/core/src/args/dev.rs b/crates/node/core/src/args/dev.rs
index b6a01745257..d62ff1c5dce 100644
--- a/crates/node/core/src/args/dev.rs
+++ b/crates/node/core/src/args/dev.rs
@@ -5,8 +5,10 @@ use std::time::Duration;
 use clap::Args;
 use humantime::parse_duration;
 
+const DEFAULT_MNEMONIC: &str = "test test test test test test test test test test test junk";
+
 /// Parameters for Dev testnet configuration
-#[derive(Debug, Args, PartialEq, Eq, Default, Clone, Copy)]
+#[derive(Debug, Args, PartialEq, Eq, Clone)]
 #[command(next_help_heading = "Dev testnet")]
 pub struct DevArgs {
     /// Start the node in dev mode
@@ -39,6 +41,28 @@ pub struct DevArgs {
         verbatim_doc_comment
     )]
     pub block_time: Option<Duration>,
+
+    /// Derive dev accounts from a fixed mnemonic instead of random ones.
+    #[arg(
+        long = "dev.mnemonic",
+        help_heading = "Dev testnet",
+        value_name = "MNEMONIC",
+        requires = "dev",
+        verbatim_doc_comment,
+        default_value = DEFAULT_MNEMONIC
+    )]
+    pub dev_mnemonic: String,
+}
+
+impl Default for DevArgs {
+    fn default() -> Self {
+        Self {
+            dev: false,
+            block_max_transactions: None,
+            block_time: None,
+            dev_mnemonic: DEFAULT_MNEMONIC.to_string(),
+        }
+    }
 }
 
 #[cfg(test)]
@@ -56,13 +80,37 @@ mod tests {
     #[test]
     fn test_parse_dev_args() {
         let args = CommandParser::<DevArgs>::parse_from(["reth"]).args;
-        assert_eq!(args, DevArgs { dev: false, block_max_transactions: None, block_time: None });
+        assert_eq!(
+            args,
+            DevArgs {
+                dev: false,
+                block_max_transactions: None,
+                block_time: None,
+                dev_mnemonic: DEFAULT_MNEMONIC.to_string(),
+            }
+        );
 
         let args = CommandParser::<DevArgs>::parse_from(["reth", "--dev"]).args;
-        assert_eq!(args, DevArgs { dev: true, block_max_transactions: None, block_time: None });
+        assert_eq!(
+            args,
+            DevArgs {
+                dev: true,
+                block_max_transactions: None,
+                block_time: None,
+                dev_mnemonic: DEFAULT_MNEMONIC.to_string(),
+            }
+        );
 
         let args = CommandParser::<DevArgs>::parse_from(["reth", "--auto-mine"]).args;
-        assert_eq!(args, DevArgs { dev: true, block_max_transactions: None, block_time: None });
+        assert_eq!(
+            args,
+            DevArgs {
+                dev: true,
+                block_max_transactions: None,
+                block_time: None,
+                dev_mnemonic: DEFAULT_MNEMONIC.to_string(),
+            }
+        );
 
         let args = CommandParser::<DevArgs>::parse_from([
             "reth",
@@ -71,7 +119,15 @@ mod tests {
             "2",
         ])
         .args;
-        assert_eq!(args, DevArgs { dev: true, block_max_transactions: Some(2), block_time: None });
+        assert_eq!(
+            args,
+            DevArgs {
+                dev: true,
+                block_max_transactions: Some(2),
+                block_time: None,
+                dev_mnemonic: DEFAULT_MNEMONIC.to_string(),
+            }
+        );
 
         let args =
             CommandParser::<DevArgs>::parse_from(["reth", "--dev", "--dev.block-time", "1s"]).args;
@@ -80,7 +136,8 @@ mod tests {
             DevArgs {
                 dev: true,
                 block_max_transactions: None,
-                block_time: Some(std::time::Duration::from_secs(1))
+                block_time: Some(std::time::Duration::from_secs(1)),
+                dev_mnemonic: DEFAULT_MNEMONIC.to_string(),
             }
         );
     }
diff --git a/crates/node/core/src/node_config.rs b/crates/node/core/src/node_config.rs
index 94dbecb649c..7b487a1fa71 100644
--- a/crates/node/core/src/node_config.rs
+++ b/crates/node/core/src/node_config.rs
@@ -272,7 +272,7 @@ impl<ChainSpec> NodeConfig<ChainSpec> {
     }
 
     /// Set the dev args for the node
-    pub const fn with_dev(mut self, dev: DevArgs) -> Self {
+    pub fn with_dev(mut self, dev: DevArgs) -> Self {
         self.dev = dev;
         self
     }
@@ -519,7 +519,7 @@ impl<ChainSpec> Clone for NodeConfig<ChainSpec> {
             builder: self.builder.clone(),
             debug: self.debug.clone(),
             db: self.db,
-            dev: self.dev,
+            dev: self.dev.clone(),
             pruning: self.pruning.clone(),
             datadir: self.datadir.clone(),
             engine: self.engine.clone(),
diff --git a/crates/optimism/rpc/src/eth/mod.rs b/crates/optimism/rpc/src/eth/mod.rs
index e10c5152473..04887d98f4c 100644
--- a/crates/optimism/rpc/src/eth/mod.rs
+++ b/crates/optimism/rpc/src/eth/mod.rs
@@ -26,19 +26,19 @@ use reth_optimism_flashblocks::{
     ExecutionPayloadBaseV1, FlashBlockBuildInfo, FlashBlockCompleteSequenceRx, FlashBlockService,
     InProgressFlashBlockRx, PendingBlockRx, PendingFlashBlock, WsFlashBlockStream,
 };
-use reth_rpc::eth::{core::EthApiInner, DevSigner};
+use reth_rpc::eth::core::EthApiInner;
 use reth_rpc_eth_api::{
     helpers::{
-        pending_block::BuildPendingEnv, AddDevSigners, EthApiSpec, EthFees, EthState, LoadFee,
-        LoadPendingBlock, LoadState, SpawnBlocking, Trace,
+        pending_block::BuildPendingEnv, EthApiSpec, EthFees, EthState, LoadFee, LoadPendingBlock,
+        LoadState, SpawnBlocking, Trace,
     },
     EthApiTypes, FromEvmError, FullEthApiServer, RpcConvert, RpcConverter, RpcNodeCore,
-    RpcNodeCoreExt, RpcTypes, SignableTxRequest,
+    RpcNodeCoreExt, RpcTypes,
 };
 use reth_rpc_eth_types::{
     EthStateCache, FeeHistoryCache, GasPriceOracle, PendingBlock, PendingBlockEnvOrigin,
 };
-use reth_storage_api::{ProviderHeader, ProviderTx};
+use reth_storage_api::ProviderHeader;
 use reth_tasks::{
     pool::{BlockingTaskGuard, BlockingTaskPool},
     TaskSpawner,
@@ -335,18 +335,6 @@ where
 {
 }
 
-impl<N, Rpc> AddDevSigners for OpEthApi<N, Rpc>
-where
-    N: RpcNodeCore,
-    Rpc: RpcConvert<
-        Network: RpcTypes<TransactionRequest: SignableTxRequest<ProviderTx<N::Provider>>>,
-    >,
-{
-    fn with_dev_accounts(&self) {
-        *self.inner.eth_api.signers().write() = DevSigner::random_signers(20)
-    }
-}
-
 impl<N: RpcNodeCore, Rpc: RpcConvert> fmt::Debug for OpEthApi<N, Rpc> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         f.debug_struct("OpEthApi").finish_non_exhaustive()
@@ -483,7 +471,7 @@ where
     NetworkT: RpcTypes,
     OpRpcConvert<N, NetworkT>: RpcConvert<Network = NetworkT>,
     OpEthApi<N, OpRpcConvert<N, NetworkT>>:
-        FullEthApiServer<Provider = N::Provider, Pool = N::Pool> + AddDevSigners,
+        FullEthApiServer<Provider = N::Provider, Pool = N::Pool>,
 {
     type EthApi = OpEthApi<N, OpRpcConvert<N, NetworkT>>;
 
diff --git a/crates/rpc/rpc-convert/src/transaction.rs b/crates/rpc/rpc-convert/src/transaction.rs
index a89104bcbaf..046acbda544 100644
--- a/crates/rpc/rpc-convert/src/transaction.rs
+++ b/crates/rpc/rpc-convert/src/transaction.rs
@@ -2,7 +2,7 @@
 
 use crate::{
     fees::{CallFees, CallFeesError},
-    RpcHeader, RpcReceipt, RpcTransaction, RpcTxReq, RpcTypes,
+    RpcHeader, RpcReceipt, RpcTransaction, RpcTxReq, RpcTypes, SignableTxRequest,
 };
 use alloy_consensus::{
     error::ValueError, transaction::Recovered, EthereumTxEnvelope, Sealable, TxEip4844,
@@ -128,7 +128,7 @@ pub trait RpcConvert: Send + Sync + Unpin + Debug + DynClone + 'static {
 
     /// Associated upper layer JSON-RPC API network requests and responses to convert from and into
     /// types of [`Self::Primitives`].
-    type Network: RpcTypes + Send + Sync + Unpin + Clone + Debug;
+    type Network: RpcTypes<TransactionRequest: SignableTxRequest<TxTy<Self::Primitives>>>;
 
     /// An associated RPC conversion error.
     type Error: error::Error + Into<jsonrpsee_types::ErrorObject<'static>>;
@@ -901,7 +901,7 @@ impl<N, Network, Evm, Receipt, Header, Map, SimTx, RpcTx, TxEnv> RpcConvert
     for RpcConverter<Network, Evm, Receipt, Header, Map, SimTx, RpcTx, TxEnv>
 where
     N: NodePrimitives,
-    Network: RpcTypes + Send + Sync + Unpin + Clone + Debug,
+    Network: RpcTypes<TransactionRequest: SignableTxRequest<N::SignedTx>>,
     Evm: ConfigureEvm<Primitives = N> + 'static,
     Receipt: ReceiptConverter<
             N,
diff --git a/crates/rpc/rpc-eth-api/src/helpers/mod.rs b/crates/rpc/rpc-eth-api/src/helpers/mod.rs
index 29223d78913..19a72ccafb7 100644
--- a/crates/rpc/rpc-eth-api/src/helpers/mod.rs
+++ b/crates/rpc/rpc-eth-api/src/helpers/mod.rs
@@ -34,7 +34,7 @@ pub use call::{Call, EthCall};
 pub use fee::{EthFees, LoadFee};
 pub use pending_block::LoadPendingBlock;
 pub use receipt::LoadReceipt;
-pub use signer::{AddDevSigners, EthSigner};
+pub use signer::EthSigner;
 pub use spec::EthApiSpec;
 pub use state::{EthState, LoadState};
 pub use trace::Trace;
diff --git a/crates/rpc/rpc-eth-api/src/helpers/signer.rs b/crates/rpc/rpc-eth-api/src/helpers/signer.rs
index 4060be138e0..c54c8943c0a 100644
--- a/crates/rpc/rpc-eth-api/src/helpers/signer.rs
+++ b/crates/rpc/rpc-eth-api/src/helpers/signer.rs
@@ -32,11 +32,3 @@ pub trait EthSigner<T, TxReq = TransactionRequest>: Send + Sync + DynClone {
 }
 
 dyn_clone::clone_trait_object!(<T> EthSigner<T>);
-
-/// Adds 20 random dev signers for access via the API. Used in dev mode.
-#[auto_impl::auto_impl(&)]
-pub trait AddDevSigners {
-    /// Generates 20 random developer accounts.
-    /// Used in DEV mode.
-    fn with_dev_accounts(&self);
-}
diff --git a/crates/rpc/rpc-eth-api/src/types.rs b/crates/rpc/rpc-eth-api/src/types.rs
index 22100520016..ed4fcfa5c80 100644
--- a/crates/rpc/rpc-eth-api/src/types.rs
+++ b/crates/rpc/rpc-eth-api/src/types.rs
@@ -2,11 +2,9 @@
 
 use crate::{AsEthApiError, FromEthApiError, RpcNodeCore};
 use alloy_rpc_types_eth::Block;
-use reth_chain_state::CanonStateSubscriptions;
-use reth_rpc_convert::RpcConvert;
+use reth_rpc_convert::{RpcConvert, SignableTxRequest};
 pub use reth_rpc_convert::{RpcTransaction, RpcTxReq, RpcTypes};
-use reth_storage_api::{ProviderTx, ReceiptProvider, TransactionsProvider};
-use reth_transaction_pool::{PoolTransaction, TransactionPool};
+use reth_storage_api::ProviderTx;
 use std::{
     error::Error,
     fmt::{self},
@@ -52,12 +50,11 @@ pub type RpcError<T> = <T as EthApiTypes>::Error;
 /// Helper trait holds necessary trait bounds on [`EthApiTypes`] to implement `eth` API.
 pub trait FullEthApiTypes
 where
-    Self: RpcNodeCore<
-            Provider: TransactionsProvider + ReceiptProvider + CanonStateSubscriptions,
-            Pool: TransactionPool<
-                Transaction: PoolTransaction<Consensus = ProviderTx<Self::Provider>>,
+    Self: RpcNodeCore
+        + EthApiTypes<
+            NetworkTypes: RpcTypes<
+                TransactionRequest: SignableTxRequest<ProviderTx<Self::Provider>>,
             >,
-        > + EthApiTypes<
             RpcConvert: RpcConvert<
                 Primitives = Self::Primitives,
                 Network = Self::NetworkTypes,
@@ -68,12 +65,11 @@ where
 }
 
 impl<T> FullEthApiTypes for T where
-    T: RpcNodeCore<
-            Provider: TransactionsProvider + ReceiptProvider + CanonStateSubscriptions,
-            Pool: TransactionPool<
-                Transaction: PoolTransaction<Consensus = ProviderTx<Self::Provider>>,
+    T: RpcNodeCore
+        + EthApiTypes<
+            NetworkTypes: RpcTypes<
+                TransactionRequest: SignableTxRequest<ProviderTx<Self::Provider>>,
             >,
-        > + EthApiTypes<
             RpcConvert: RpcConvert<
                 Primitives = <Self as RpcNodeCore>::Primitives,
                 Network = Self::NetworkTypes,
diff --git a/crates/rpc/rpc/Cargo.toml b/crates/rpc/rpc/Cargo.toml
index c47c383f057..e028e47448d 100644
--- a/crates/rpc/rpc/Cargo.toml
+++ b/crates/rpc/rpc/Cargo.toml
@@ -45,7 +45,7 @@ reth-trie-common.workspace = true
 alloy-evm = { workspace = true, features = ["overrides"] }
 alloy-consensus.workspace = true
 alloy-signer.workspace = true
-alloy-signer-local.workspace = true
+alloy-signer-local = { workspace = true, features = ["mnemonic"] }
 alloy-eips = { workspace = true, features = ["kzg"] }
 alloy-dyn-abi.workspace = true
 alloy-genesis.workspace = true
diff --git a/crates/rpc/rpc/src/eth/helpers/signer.rs b/crates/rpc/rpc/src/eth/helpers/signer.rs
index 60d6a151f9b..2c18245d542 100644
--- a/crates/rpc/rpc/src/eth/helpers/signer.rs
+++ b/crates/rpc/rpc/src/eth/helpers/signer.rs
@@ -1,33 +1,14 @@
 //! An abstraction over ethereum signers.
 
-use std::collections::HashMap;
-
-use crate::EthApi;
 use alloy_dyn_abi::TypedData;
 use alloy_eips::eip2718::Decodable2718;
 use alloy_primitives::{eip191_hash_message, Address, Signature, B256};
 use alloy_signer::SignerSync;
-use alloy_signer_local::PrivateKeySigner;
-use reth_rpc_convert::{RpcConvert, RpcTypes, SignableTxRequest};
-use reth_rpc_eth_api::{
-    helpers::{signer::Result, AddDevSigners, EthSigner},
-    FromEvmError, RpcNodeCore,
-};
-use reth_rpc_eth_types::{EthApiError, SignError};
-use reth_storage_api::ProviderTx;
-
-impl<N, Rpc> AddDevSigners for EthApi<N, Rpc>
-where
-    N: RpcNodeCore,
-    EthApiError: FromEvmError<N::Evm>,
-    Rpc: RpcConvert<
-        Network: RpcTypes<TransactionRequest: SignableTxRequest<ProviderTx<N::Provider>>>,
-    >,
-{
-    fn with_dev_accounts(&self) {
-        *self.inner.signers().write() = DevSigner::random_signers(20)
-    }
-}
+use alloy_signer_local::{coins_bip39::English, MnemonicBuilder, PrivateKeySigner};
+use reth_rpc_convert::SignableTxRequest;
+use reth_rpc_eth_api::helpers::{signer::Result, EthSigner};
+use reth_rpc_eth_types::SignError;
+use std::collections::HashMap;
 
 /// Holds developer keys
 #[derive(Debug, Clone)]
@@ -55,6 +36,32 @@ impl DevSigner {
         signers
     }
 
+    /// Generates dev signers deterministically from a fixed mnemonic.
+    /// Uses the Ethereum derivation path: `m/44'/60'/0'/0/{index}`
+    pub fn from_mnemonic<T: Decodable2718, TxReq: SignableTxRequest<T>>(
+        mnemonic: &str,
+        num: u32,
+    ) -> Vec<Box<dyn EthSigner<T, TxReq> + 'static>> {
+        let mut signers = Vec::with_capacity(num as usize);
+
+        for i in 0..num {
+            let sk = MnemonicBuilder::<English>::default()
+                .phrase(mnemonic)
+                .index(i)
+                .expect("invalid derivation path")
+                .build()
+                .expect("failed to build signer from mnemonic");
+
+            let address = sk.address();
+            let addresses = vec![address];
+            let accounts = HashMap::from([(address, sk)]);
+
+            signers.push(Box::new(Self { addresses, accounts }) as Box<dyn EthSigner<T, TxReq>>);
+        }
+
+        signers
+    }
+
     fn get_key(&self, account: Address) -> Result<&PrivateKeySigner> {
         self.accounts.get(&account).ok_or(SignError::NoAccount)
     }
diff --git a/docs/vocs/docs/pages/cli/reth/node.mdx b/docs/vocs/docs/pages/cli/reth/node.mdx
index 9b46593a3de..5d07845a8e1 100644
--- a/docs/vocs/docs/pages/cli/reth/node.mdx
+++ b/docs/vocs/docs/pages/cli/reth/node.mdx
@@ -734,6 +734,11 @@ Dev testnet:
           Parses strings using [`humantime::parse_duration`]
           --dev.block-time 12s
 
+      --dev.mnemonic <MNEMONIC>
+          Derive dev accounts from a fixed mnemonic instead of random ones.
+
+          [default: "test test test test test test test test test test test junk"]
+
 Pruning:
       --full
           Run full node. Only the most recent [`MINIMUM_PRUNING_DISTANCE`] block states are stored