diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..993c31d
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,3 @@
+.idea
+target
+**/*.rs.bk
diff --git a/Cargo.lock b/Cargo.lock
new file mode 100644
index 0000000..7ac2b71
--- /dev/null
+++ b/Cargo.lock
@@ -0,0 +1,4 @@
+[[package]]
+name = "ambient-ast"
+version = "0.1.0"
+
diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..3cdd286
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,5 @@
+[workspace]
+
+members = [
+    "ambient-ast"
+]
\ No newline at end of file
diff --git a/README.md b/README.md
index 92d0a47..1c41586 100644
--- a/README.md
+++ b/README.md
@@ -1,2 +1,4 @@
-# ambient-engine
-Ambient engine
+# Ambient Engine
+
+The Ambient Engine is the implementation of the orchestrator on top 
+of the Typed Ambient Calculus with Resources. 
diff --git a/ambient-ast/Cargo.toml b/ambient-ast/Cargo.toml
new file mode 100644
index 0000000..7f3d22c
--- /dev/null
+++ b/ambient-ast/Cargo.toml
@@ -0,0 +1,8 @@
+[package]
+name = "ambient-ast"
+version = "0.1.0"
+authors = ["Alessio Coltellacci <lightplay8@gmail.com>",  "Didier Plaindoux <d.plaindoux@free.fr>"]
+edition = "2018"
+
+[dependencies]
+
diff --git a/ambient-ast/README.md b/ambient-ast/README.md
new file mode 100644
index 0000000..408f7fa
--- /dev/null
+++ b/ambient-ast/README.md
@@ -0,0 +1,32 @@
+# Ambient AST
+
+This crate provides intermediate Abstract Syntax Tree (AST) for the compilation process.
+These definitions came from the 
+[Cardellis' Paper](http://lucacardelli.name/Papers/MobileAmbients.A4.pdf).
+
+## Capabilities
+
+```
+M ::=              -- Capability
+   x                -- variable
+    n               -- name
+    in M            -- enter
+    out M           -- exit
+    open M          -- open
+    ε               -- empty
+    M.M′            -- path
+```
+
+## Processes 
+
+```
+P,Q ::=
+    (νn)P           -- restriction
+    0               -- inactivity
+    P|Q             -- composition
+    !P              -- replication
+    M[P]            -- ambient
+    M.P             -- capability action
+    (x).P           -- input action
+    <M>             -- async output action
+```
diff --git a/ambient-ast/src/ast/capabilities.rs b/ambient-ast/src/ast/capabilities.rs
new file mode 100644
index 0000000..9241ae4
--- /dev/null
+++ b/ambient-ast/src/ast/capabilities.rs
@@ -0,0 +1,158 @@
+//! This is the documentation to capabilities module
+
+/// The `Capability` type. See [Cardellis' Paper](http://lucacardelli.name/Papers/MobileAmbients.A4.pdf) page 20.
+///
+/// ```text
+/// M ::=              -- Capability
+///   x                -- variable
+///    n               -- name
+///    in M            -- enter
+///    out M           -- exit
+///    open M          -- open
+///    ε               -- empty
+///    M.M′            -- path
+/// ```
+///
+pub trait Capability {}
+
+/// `Variable` capability for dynamic purposes
+#[derive(Debug)]
+pub struct Variable<S>
+    where
+        S: Into<String>,
+{
+    pub value: S,
+}
+
+/// `Name` for action target or ambient namespace definition
+#[derive(Debug)]
+pub struct Name<S>
+    where
+        S: Into<String>,
+{
+    pub value: S,
+}
+
+/// `In` enter a sibling named ambient
+#[derive(Debug)]
+pub struct In<M: Capability> {
+    pub capability: M,
+}
+
+/// `Out` exit a parent named ambient
+#[derive(Debug)]
+pub struct Out<M>
+    where
+        M: Capability,
+{
+    pub capability: M,
+}
+
+/// `Open` dissolve a sibling named abient
+#[derive(Debug)]
+pub struct Open<M>
+    where
+        M: Capability,
+{
+    pub capability: M,
+}
+
+/// `Path` composition of two sequential capabilities. The left one should be done before.
+#[derive(Debug)]
+pub struct Path<N, M>
+    where
+        N: Capability,
+        M: Capability,
+{
+    pub capability_l: N,
+    pub capability_r: M,
+}
+
+/// `Empty` capability meaning nothing to be done
+pub struct Empty;
+
+// Kind of Capability
+
+impl<S> Capability for Variable<S> where S: Into<String> {}
+
+impl<S> Capability for Name<S> where S: Into<String> {}
+
+impl<M> Capability for In<M> where M: Capability {}
+
+impl<M> Capability for Out<M> where M: Capability {}
+
+impl<M> Capability for Open<M> where M: Capability {}
+
+impl<N, M> Capability for Path<N, M>
+    where
+        N: Capability,
+        M: Capability,
+{}
+
+impl Capability for Empty {}
+
+// Factories
+
+impl<S> Variable<S>
+    where
+        S: Into<String>,
+{
+    pub fn new(value: S) -> Self {
+        Self { value }
+    }
+}
+
+impl<S> Name<S>
+    where
+        S: Into<String>,
+{
+    pub fn new(value: S) -> Self {
+        Self { value }
+    }
+}
+
+impl<M> In<M>
+    where
+        M: Capability,
+{
+    pub fn new(capability: M) -> Self {
+        Self { capability }
+    }
+}
+
+impl<M> Out<M>
+    where
+        M: Capability,
+{
+    pub fn new(capability: M) -> Self {
+        Self { capability }
+    }
+}
+
+impl<M> Open<M>
+    where
+        M: Capability,
+{
+    pub fn new(capability: M) -> Self {
+        Self { capability }
+    }
+}
+
+impl<N, M> Path<N, M>
+    where
+        N: Capability,
+        M: Capability,
+{
+    pub fn new(capability_l: N, capability_r: M) -> Self {
+        Self {
+            capability_l,
+            capability_r,
+        }
+    }
+}
+
+impl Empty {
+    pub fn new() -> Self {
+        Self
+    }
+}
diff --git a/ambient-ast/src/ast/mod.rs b/ambient-ast/src/ast/mod.rs
new file mode 100644
index 0000000..6249573
--- /dev/null
+++ b/ambient-ast/src/ast/mod.rs
@@ -0,0 +1,2 @@
+pub mod capabilities;
+pub mod processes;
diff --git a/ambient-ast/src/ast/processes.rs b/ambient-ast/src/ast/processes.rs
new file mode 100644
index 0000000..7e4889d
--- /dev/null
+++ b/ambient-ast/src/ast/processes.rs
@@ -0,0 +1,224 @@
+//! This is the documentation to processes module
+
+use crate::ast::capabilities::*;
+
+/// The `Process` type. See [Cardellis' Paper](http://lucacardelli.name/Papers/MobileAmbients.A4.pdf) page 20.
+///
+/// ```text
+/// P,Q ::=
+///    (νn)P           -- restriction
+///    0               -- inactivity
+///    P|Q             -- composition
+///    !P              -- replication
+///    M[P]            -- ambient
+///    M.P             -- capability action
+///    (x).P           -- input action
+///    <M>             -- async output action
+///```
+///
+pub trait Process {}
+
+/// `Restriction` defines a process with a private name
+#[derive(Debug)]
+pub struct Restriction<S, P>
+where
+    S: Into<String>,
+    P: Process,
+{
+    pub name: S,
+    pub process: P,
+}
+
+/// `Inactivity` defines a process doing nothing
+#[derive(Debug)]
+pub struct Inactivity;
+
+/// `Composition` defines a two processes running in parallel
+#[derive(Debug)]
+pub struct Composition<P, Q>
+where
+    P: Process,
+    Q: Process,
+{
+    pub process_l: P,
+    pub process_r: Q,
+}
+
+/// `Replication` defines a perpetual process where `!P` is isomorphic to `P | !P`
+#[derive(Debug)]
+pub struct Replication<P>
+where
+    P: Process,
+{
+    pub process: P,
+}
+
+/// `Ambient` defines a named bounded space containing processes
+#[derive(Debug)]
+pub struct Ambient<M, P>
+where
+    M: Capability,
+    P: Process,
+{
+    pub capability: M,
+    pub process: P,
+}
+
+/// `Action` attach a capability to a given process defining an action to be done
+#[derive(Debug)]
+pub struct Action<M, P>
+where
+    M: Capability,
+    P: Process,
+{
+    pub capability: M,
+    pub process: P,
+}
+
+/// `Input` defines the function able to capture a message.
+#[derive(Debug)]
+pub struct Input<X, P>
+where
+    X: Into<String>,
+    P: Process,
+{
+    pub variable: X,
+    pub process: P,
+}
+
+/// `Output` defines the message able to be captured by an `Input`
+#[derive(Debug)]
+pub struct Output<M>
+where
+    M: Capability,
+{
+    pub message: M,
+}
+
+// Kind of process
+
+impl<N, P> Process for Restriction<N, P>
+where
+    N: Into<String>,
+    P: Process,
+{
+}
+
+impl Process for Inactivity {}
+
+impl<P, Q> Process for Composition<P, Q>
+where
+    P: Process,
+    Q: Process,
+{
+}
+
+impl<P> Process for Replication<P> where P: Process {}
+
+impl<M, P> Process for Ambient<M, P>
+where
+    M: Capability,
+    P: Process,
+{
+}
+
+impl<M, P> Process for Action<M, P>
+where
+    M: Capability,
+    P: Process,
+{
+}
+
+impl<X, P> Process for Input<X, P>
+where
+    X: Into<String>,
+    P: Process,
+{
+}
+
+impl<M> Process for Output<M> where M: Capability {}
+
+// Factories
+
+impl<S, P> Restriction<S, P>
+where
+    S: Into<String>,
+    P: Process,
+{
+    pub fn new(name: S, process: P) -> Self {
+        Self { name, process }
+    }
+}
+
+impl Inactivity {
+    pub fn new() -> Self {
+        Inactivity
+    }
+}
+
+impl<P, Q> Composition<P, Q>
+where
+    P: Process,
+    Q: Process,
+{
+    pub fn new(process_l: P, process_r: Q) -> Self {
+        Self {
+            process_l,
+            process_r,
+        }
+    }
+}
+
+impl<P> Replication<P>
+where
+    P: Process,
+{
+    pub fn new(process: P) -> Self {
+        Self { process }
+    }
+}
+
+impl<M, P> Ambient<M, P>
+where
+    M: Capability,
+    P: Process,
+{
+    pub fn new(capability: M, process: P) -> Self {
+        Self {
+            capability,
+            process,
+        }
+    }
+}
+
+impl<M, P> Action<M, P>
+where
+    M: Capability,
+    P: Process,
+{
+    pub fn new(capability: M, process: P) -> Self {
+        Self {
+            capability,
+            process,
+        }
+    }
+}
+
+impl<X, P> Input<X, P>
+where
+    X: Into<String>,
+    P: Process,
+{
+    pub fn new(variable: X, process: P) -> Self {
+        Self { variable, process }
+    }
+}
+
+impl<M> Output<M>
+where
+    M: Capability,
+{
+    pub fn new(message: M) -> Self {
+        Self { message }
+    }
+}
diff --git a/ambient-ast/src/lib.rs b/ambient-ast/src/lib.rs
new file mode 100644
index 0000000..851c0bc
--- /dev/null
+++ b/ambient-ast/src/lib.rs
@@ -0,0 +1 @@
+pub mod ast;