diff --git a/Cargo.toml b/Cargo.toml
index d89a973..a419ffe 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -4,7 +4,7 @@ name = "init4-bin-base"
 description = "Internal utilities for binaries produced by the init4 team"
 keywords = ["init4", "bin", "base"]
 
-version = "0.12.4"
+version = "0.12.5"
 edition = "2021"
 rust-version = "1.83"
 authors = ["init4", "James Prestwich", "evalir"]
diff --git a/src/utils/calc.rs b/src/utils/calc.rs
index 733e947..7197b04 100644
--- a/src/utils/calc.rs
+++ b/src/utils/calc.rs
@@ -263,7 +263,7 @@ impl SlotCalculator {
 }
 
 impl FromEnv for SlotCalculator {
-    type Error = FromEnvErr<ParseIntError>;
+    type Error = ParseIntError;
 
     fn inventory() -> Vec<&'static EnvItemInfo> {
         vec![
diff --git a/src/utils/from_env.rs b/src/utils/from_env.rs
index 357c37d..c2d429f 100644
--- a/src/utils/from_env.rs
+++ b/src/utils/from_env.rs
@@ -1,5 +1,5 @@
 use signet_constants::{
-    HostConstants, RollupConstants, SignetConstants, SignetEnvironmentConstants,
+    HostConstants, ParseChainError, RollupConstants, SignetConstants, SignetEnvironmentConstants,
     SignetSystemConstants,
 };
 use std::{convert::Infallible, env::VarError, num::ParseIntError, str::FromStr};
@@ -670,6 +670,23 @@ impl FromEnvVar for tracing::Level {
     }
 }
 
+impl FromEnv for SignetSystemConstants {
+    type Error = ParseChainError;
+
+    fn inventory() -> Vec<&'static EnvItemInfo> {
+        vec![&EnvItemInfo {
+            var: "CHAIN_NAME",
+            description:
+                "The name of the chain. If set, the other environment variables are ignored.",
+            optional: true,
+        }]
+    }
+
+    fn from_env() -> Result<Self, FromEnvErr<Self::Error>> {
+        SignetSystemConstants::from_env_var("CHAIN_NAME")
+    }
+}
+
 #[cfg(test)]
 mod test {
     use std::{borrow::Cow, time::Duration};