diff --git a/crates/aiken-lang/src/ast.rs b/crates/aiken-lang/src/ast.rs
index 885c2576..dae941c2 100644
--- a/crates/aiken-lang/src/ast.rs
+++ b/crates/aiken-lang/src/ast.rs
@@ -21,6 +21,9 @@ pub const BACKPASS_VARIABLE: &str = "_backpass";
 pub const CAPTURE_VARIABLE: &str = "_capture";
 pub const PIPE_VARIABLE: &str = "_pipe";
 
+pub const ENV_MODULE: &str = "env";
+pub const DEFAULT_ENV_MODULE: &str = "default";
+
 pub type TypedModule = Module<TypeInfo, TypedDefinition>;
 pub type UntypedModule = Module<(), UntypedDefinition>;
 
diff --git a/crates/aiken-lang/src/lib.rs b/crates/aiken-lang/src/lib.rs
index 2910c3f3..c0ed6894 100644
--- a/crates/aiken-lang/src/lib.rs
+++ b/crates/aiken-lang/src/lib.rs
@@ -49,6 +49,7 @@ macro_rules! aiken_fn {
                 $module_types,
                 $crate::ast::Tracing::silent(),
                 &mut warnings,
+                None,
             )
             .unwrap();
 
diff --git a/crates/aiken-lang/src/tests/check.rs b/crates/aiken-lang/src/tests/check.rs
index ecf1c528..906240e7 100644
--- a/crates/aiken-lang/src/tests/check.rs
+++ b/crates/aiken-lang/src/tests/check.rs
@@ -38,6 +38,7 @@ fn check_module(
                 &module_types,
                 Tracing::All(TraceLevel::Verbose),
                 &mut warnings,
+                None,
             )
             .expect("extra dependency did not compile");
         module_types.insert(package.clone(), typed_module.type_info.clone());
@@ -50,6 +51,7 @@ fn check_module(
         &module_types,
         tracing,
         &mut warnings,
+        None,
     );
 
     result
diff --git a/crates/aiken-lang/src/tipo/environment.rs b/crates/aiken-lang/src/tipo/environment.rs
index 564afa19..4548bc7a 100644
--- a/crates/aiken-lang/src/tipo/environment.rs
+++ b/crates/aiken-lang/src/tipo/environment.rs
@@ -7,7 +7,7 @@ use super::{
 };
 use crate::{
     ast::{
-        Annotation, CallArg, DataType, Definition, Function, ModuleConstant, ModuleKind,
+        self, Annotation, CallArg, DataType, Definition, Function, ModuleConstant, ModuleKind,
         RecordConstructor, RecordConstructorArg, Span, TypeAlias, TypedDefinition, TypedFunction,
         TypedPattern, UnqualifiedImport, UntypedArg, UntypedDefinition, UntypedFunction, Use,
         Validator, PIPE_VARIABLE,
@@ -80,11 +80,33 @@ pub struct Environment<'a> {
     /// A mapping from known annotations to their resolved type.
     pub annotations: HashMap<Annotation, Rc<Type>>,
 
+    /// The user-defined target environment referred to as the module 'env'.
+    pub target_env: Option<&'a str>,
+
     /// Warnings
     pub warnings: &'a mut Vec<Warning>,
 }
 
 impl<'a> Environment<'a> {
+    pub fn find_module(&self, fragments: &[String], location: Span) -> Result<&'a TypeInfo, Error> {
+        let mut name = fragments.join("/");
+
+        if name == ast::ENV_MODULE {
+            name = self
+                .target_env
+                .unwrap_or(ast::DEFAULT_ENV_MODULE)
+                .to_string()
+        }
+
+        self.importable_modules
+            .get(&name)
+            .ok_or_else(|| Error::UnknownModule {
+                location,
+                name,
+                imported_modules: self.imported_modules.keys().cloned().collect(),
+            })
+    }
+
     pub fn close_scope(&mut self, data: ScopeResetData) {
         let unused = self
             .entity_usages
@@ -705,6 +727,7 @@ impl<'a> Environment<'a> {
         current_kind: &'a ModuleKind,
         importable_modules: &'a HashMap<String, TypeInfo>,
         warnings: &'a mut Vec<Warning>,
+        target_env: Option<&'a str>,
     ) -> Self {
         let prelude = importable_modules
             .get("aiken")
@@ -731,6 +754,7 @@ impl<'a> Environment<'a> {
             annotations: HashMap::new(),
             warnings,
             entity_usages: vec![HashMap::new()],
+            target_env,
         }
     }
 
@@ -772,17 +796,7 @@ impl<'a> Environment<'a> {
                 location,
                 package: _,
             }) => {
-                let name = module.join("/");
-
-                // Find imported module
-                let module_info =
-                    self.importable_modules
-                        .get(&name)
-                        .ok_or_else(|| Error::UnknownModule {
-                            location: *location,
-                            name: name.clone(),
-                            imported_modules: self.imported_modules.keys().cloned().collect(),
-                        })?;
+                let module_info = self.find_module(module, *location)?;
 
                 if module_info.kind.is_validator()
                     && (self.current_kind.is_lib()
@@ -791,7 +805,7 @@ impl<'a> Environment<'a> {
                 {
                     return Err(Error::ValidatorImported {
                         location: *location,
-                        name,
+                        name: module.join("/"),
                     });
                 }
 
diff --git a/crates/aiken-lang/src/tipo/infer.rs b/crates/aiken-lang/src/tipo/infer.rs
index b9a35b0e..8f9a37a6 100644
--- a/crates/aiken-lang/src/tipo/infer.rs
+++ b/crates/aiken-lang/src/tipo/infer.rs
@@ -19,6 +19,7 @@ use crate::{
 use std::{borrow::Borrow, collections::HashMap, ops::Deref, rc::Rc};
 
 impl UntypedModule {
+    #[allow(clippy::too_many_arguments)]
     pub fn infer(
         mut self,
         id_gen: &IdGenerator,
@@ -27,11 +28,12 @@ impl UntypedModule {
         modules: &HashMap<String, TypeInfo>,
         tracing: Tracing,
         warnings: &mut Vec<Warning>,
+        env: Option<&str>,
     ) -> Result<TypedModule, Error> {
         let module_name = self.name.clone();
         let docs = std::mem::take(&mut self.docs);
         let mut environment =
-            Environment::new(id_gen.clone(), &module_name, &kind, modules, warnings);
+            Environment::new(id_gen.clone(), &module_name, &kind, modules, warnings, env);
 
         let mut type_names = HashMap::with_capacity(self.definitions.len());
         let mut value_names = HashMap::with_capacity(self.definitions.len());
@@ -574,18 +576,7 @@ fn infer_definition(
             unqualified,
             package: _,
         }) => {
-            let name = module.join("/");
-
-            // Find imported module
-            let module_info =
-                environment
-                    .importable_modules
-                    .get(&name)
-                    .ok_or_else(|| Error::UnknownModule {
-                        location,
-                        name,
-                        imported_modules: environment.imported_modules.keys().cloned().collect(),
-                    })?;
+            let module_info = environment.find_module(&module, location)?;
 
             Ok(Definition::Use(Use {
                 location,
diff --git a/crates/aiken-lsp/src/server/lsp_project.rs b/crates/aiken-lsp/src/server/lsp_project.rs
index eda2d020..efd36ab6 100644
--- a/crates/aiken-lsp/src/server/lsp_project.rs
+++ b/crates/aiken-lsp/src/server/lsp_project.rs
@@ -40,6 +40,7 @@ impl LspProject {
             u32::default(),
             PropertyTest::DEFAULT_MAX_SUCCESS,
             Tracing::silent(),
+            None,
         );
 
         self.project.restore(checkpoint);
diff --git a/crates/aiken-project/src/lib.rs b/crates/aiken-project/src/lib.rs
index 2af5f0eb..e3e7607c 100644
--- a/crates/aiken-project/src/lib.rs
+++ b/crates/aiken-project/src/lib.rs
@@ -32,7 +32,7 @@ use crate::{
 };
 use aiken_lang::{
     ast::{
-        DataTypeKey, Definition, FunctionAccessKey, ModuleKind, Tracing, TypedDataType,
+        self, DataTypeKey, Definition, FunctionAccessKey, ModuleKind, Tracing, TypedDataType,
         TypedFunction,
     },
     builtins,
@@ -65,8 +65,6 @@ use uplc::{
     PlutusData,
 };
 
-const DEFAULT_ENV_MODULE: &str = "default";
-
 #[derive(Debug)]
 pub struct Source {
     pub path: PathBuf,
@@ -186,10 +184,16 @@ where
         self.defined_modules = checkpoint.defined_modules;
     }
 
-    pub fn build(&mut self, uplc: bool, tracing: Tracing) -> Result<(), Vec<Error>> {
+    pub fn build(
+        &mut self,
+        uplc: bool,
+        tracing: Tracing,
+        env: Option<String>,
+    ) -> Result<(), Vec<Error>> {
         let options = Options {
             code_gen_mode: CodeGenMode::Build(uplc),
             tracing,
+            env,
         };
 
         self.compile(options)
@@ -211,7 +215,7 @@ where
 
         let mut modules = self.parse_sources(self.config.name.clone())?;
 
-        self.type_check(&mut modules, Tracing::silent(), false)?;
+        self.type_check(&mut modules, Tracing::silent(), None, false)?;
 
         let destination = destination.unwrap_or_else(|| self.root.join("docs"));
 
@@ -252,9 +256,11 @@ where
         seed: u32,
         property_max_success: usize,
         tracing: Tracing,
+        env: Option<String>,
     ) -> Result<(), Vec<Error>> {
         let options = Options {
             tracing,
+            env,
             code_gen_mode: if skip_tests {
                 CodeGenMode::NoOp
             } else {
@@ -307,7 +313,7 @@ where
 
         let mut modules = self.parse_sources(self.config.name.clone())?;
 
-        self.type_check(&mut modules, options.tracing, true)?;
+        self.type_check(&mut modules, options.tracing, options.env.as_deref(), true)?;
 
         match options.code_gen_mode {
             CodeGenMode::Build(uplc_dump) => {
@@ -725,6 +731,7 @@ where
         &mut self,
         modules: &mut ParsedModules,
         tracing: Tracing,
+        env: Option<&str>,
         validate_module_name: bool,
     ) -> Result<(), Vec<Error>> {
         let our_modules: BTreeSet<String> = modules.keys().cloned().collect();
@@ -737,6 +744,7 @@ where
                     &self.id_gen,
                     &self.config.name.to_string(),
                     tracing,
+                    env,
                     validate_module_name,
                     &mut self.module_sources,
                     &mut self.module_types,
@@ -905,7 +913,7 @@ where
                 }
 
                 if keep {
-                    if self.module_name(dir, &path).as_str() == DEFAULT_ENV_MODULE {
+                    if self.module_name(dir, &path).as_str() == ast::DEFAULT_ENV_MODULE {
                         has_default = Some(true);
                     }
                     self.add_module(path, dir, kind)
diff --git a/crates/aiken-project/src/module.rs b/crates/aiken-project/src/module.rs
index 49aad2a5..804d5c6b 100644
--- a/crates/aiken-project/src/module.rs
+++ b/crates/aiken-project/src/module.rs
@@ -51,6 +51,7 @@ impl ParsedModule {
         id_gen: &IdGenerator,
         package: &str,
         tracing: Tracing,
+        env: Option<&str>,
         validate_module_name: bool,
         module_sources: &mut HashMap<String, (String, LineNumbers)>,
         module_types: &mut HashMap<String, TypeInfo>,
@@ -68,6 +69,7 @@ impl ParsedModule {
                 module_types,
                 tracing,
                 &mut warnings,
+                env,
             )
             .map_err(|error| Error::Type {
                 path: self.path.clone(),
diff --git a/crates/aiken-project/src/options.rs b/crates/aiken-project/src/options.rs
index aa0a8d33..c1551706 100644
--- a/crates/aiken-project/src/options.rs
+++ b/crates/aiken-project/src/options.rs
@@ -3,6 +3,7 @@ use aiken_lang::ast::Tracing;
 pub struct Options {
     pub code_gen_mode: CodeGenMode,
     pub tracing: Tracing,
+    pub env: Option<String>,
 }
 
 impl Default for Options {
@@ -10,6 +11,7 @@ impl Default for Options {
         Self {
             code_gen_mode: CodeGenMode::NoOp,
             tracing: Tracing::silent(),
+            env: None,
         }
     }
 }
diff --git a/crates/aiken-project/src/test_framework.rs b/crates/aiken-project/src/test_framework.rs
index 2ca9e5ba..60e005c4 100644
--- a/crates/aiken-project/src/test_framework.rs
+++ b/crates/aiken-project/src/test_framework.rs
@@ -1314,6 +1314,7 @@ mod test {
                     &module_types,
                     Tracing::All(TraceLevel::Verbose),
                     &mut warnings,
+                    None,
                 )
                 .expect("Failed to type-check module.");
 
diff --git a/crates/aiken-project/src/tests/mod.rs b/crates/aiken-project/src/tests/mod.rs
index d0967542..6039c89c 100644
--- a/crates/aiken-project/src/tests/mod.rs
+++ b/crates/aiken-project/src/tests/mod.rs
@@ -99,6 +99,7 @@ impl TestProject {
                 &self.module_types,
                 Tracing::All(TraceLevel::Verbose),
                 &mut warnings,
+                None,
             )
             .expect("Failed to type-check module");
 
diff --git a/crates/aiken/src/cmd/blueprint/address.rs b/crates/aiken/src/cmd/blueprint/address.rs
index 285b30d3..df54879e 100644
--- a/crates/aiken/src/cmd/blueprint/address.rs
+++ b/crates/aiken/src/cmd/blueprint/address.rs
@@ -1,4 +1,3 @@
-use aiken_lang::ast::Tracing;
 use aiken_project::watch::with_project;
 use std::path::PathBuf;
 
@@ -20,10 +19,6 @@ pub struct Args {
     #[clap(long)]
     delegated_to: Option<String>,
 
-    /// Force the project to be rebuilt, otherwise relies on existing artifacts (i.e. plutus.json)
-    #[clap(long)]
-    rebuild: bool,
-
     /// Output the address for mainnet (this command defaults to testnet)
     #[clap(long)]
     mainnet: bool,
@@ -35,15 +30,10 @@ pub fn exec(
         module,
         validator,
         delegated_to,
-        rebuild,
         mainnet,
     }: Args,
 ) -> miette::Result<()> {
     with_project(directory.as_deref(), false, |p| {
-        if rebuild {
-            p.build(false, Tracing::silent())?;
-        }
-
         let title = module.as_ref().map(|m| {
             format!(
                 "{m}{}",
diff --git a/crates/aiken/src/cmd/blueprint/hash.rs b/crates/aiken/src/cmd/blueprint/hash.rs
index ef67e702..c7370890 100644
--- a/crates/aiken/src/cmd/blueprint/hash.rs
+++ b/crates/aiken/src/cmd/blueprint/hash.rs
@@ -1,4 +1,3 @@
-use aiken_lang::ast::Tracing;
 use aiken_project::watch::with_project;
 use std::path::PathBuf;
 
@@ -15,10 +14,6 @@ pub struct Args {
     /// Name of the validator within the module. Optional if there's only one validator
     #[clap(short, long)]
     validator: Option<String>,
-
-    /// Force the project to be rebuilt, otherwise relies on existing artifacts (i.e. plutus.json)
-    #[clap(long)]
-    rebuild: bool,
 }
 
 pub fn exec(
@@ -26,14 +21,9 @@ pub fn exec(
         directory,
         module,
         validator,
-        rebuild,
     }: Args,
 ) -> miette::Result<()> {
     with_project(directory.as_deref(), false, |p| {
-        if rebuild {
-            p.build(false, Tracing::silent())?;
-        }
-
         let title = module.as_ref().map(|m| {
             format!(
                 "{m}{}",
diff --git a/crates/aiken/src/cmd/blueprint/policy.rs b/crates/aiken/src/cmd/blueprint/policy.rs
index 80c90d4c..e23f118c 100644
--- a/crates/aiken/src/cmd/blueprint/policy.rs
+++ b/crates/aiken/src/cmd/blueprint/policy.rs
@@ -1,4 +1,3 @@
-use aiken_lang::ast::Tracing;
 use aiken_project::watch::with_project;
 use std::path::PathBuf;
 
@@ -15,10 +14,6 @@ pub struct Args {
     /// Name of the validator within the module. Optional if there's only one validator
     #[clap(short, long)]
     validator: Option<String>,
-
-    /// Force the project to be rebuilt, otherwise relies on existing artifacts (i.e. plutus.json)
-    #[clap(long)]
-    rebuild: bool,
 }
 
 pub fn exec(
@@ -26,14 +21,9 @@ pub fn exec(
         directory,
         module,
         validator,
-        rebuild,
     }: Args,
 ) -> miette::Result<()> {
     with_project(directory.as_deref(), false, |p| {
-        if rebuild {
-            p.build(false, Tracing::silent())?;
-        }
-
         let title = module.as_ref().map(|m| {
             format!(
                 "{m}{}",
diff --git a/crates/aiken/src/cmd/build.rs b/crates/aiken/src/cmd/build.rs
index a5b60499..fbe89fba 100644
--- a/crates/aiken/src/cmd/build.rs
+++ b/crates/aiken/src/cmd/build.rs
@@ -21,6 +21,10 @@ pub struct Args {
     #[clap(short, long)]
     uplc: bool,
 
+    /// Environment to build against.
+    #[clap(long)]
+    env: Option<String>,
+
     /// Filter traces to be included in the generated program(s).
     ///
     ///   - user-defined:
@@ -63,6 +67,7 @@ pub fn exec(
         uplc,
         filter_traces,
         trace_level,
+        env,
     }: Args,
 ) -> miette::Result<()> {
     let result = if watch {
@@ -73,6 +78,7 @@ pub fn exec(
                     Some(filter_traces) => filter_traces(trace_level),
                     None => Tracing::All(trace_level),
                 },
+                env.clone(),
             )
         })
     } else {
@@ -83,6 +89,7 @@ pub fn exec(
                     Some(filter_traces) => filter_traces(trace_level),
                     None => Tracing::All(trace_level),
                 },
+                env.clone(),
             )
         })
     };
diff --git a/crates/aiken/src/cmd/check.rs b/crates/aiken/src/cmd/check.rs
index 92f89d3a..d83c437f 100644
--- a/crates/aiken/src/cmd/check.rs
+++ b/crates/aiken/src/cmd/check.rs
@@ -48,6 +48,10 @@ pub struct Args {
     #[clap(short, long)]
     exact_match: bool,
 
+    /// Environment to build against.
+    #[clap(long)]
+    env: Option<String>,
+
     /// Filter traces to be included in the generated program(s).
     ///
     ///   - user-defined:
@@ -95,6 +99,7 @@ pub fn exec(
         trace_level,
         seed,
         max_success,
+        env,
     }: Args,
 ) -> miette::Result<()> {
     let mut rng = rand::thread_rng();
@@ -114,6 +119,7 @@ pub fn exec(
                     Some(filter_traces) => filter_traces(trace_level),
                     None => Tracing::All(trace_level),
                 },
+                env.clone(),
             )
         })
     } else {
@@ -129,6 +135,7 @@ pub fn exec(
                     Some(filter_traces) => filter_traces(trace_level),
                     None => Tracing::All(trace_level),
                 },
+                env.clone(),
             )
         })
     };