diff --git a/.idea/acrate.iml b/.idea/acrate.iml
index 05d6838..030fecb 100644
--- a/.idea/acrate.iml
+++ b/.idea/acrate.iml
@@ -13,9 +13,10 @@
       <sourceFolder url="file://$MODULE_DIR$/acrate_rdserver/src" isTestSource="false" />
       <sourceFolder url="file://$MODULE_DIR$/acrate_apub_inbox/src" isTestSource="false" />
       <sourceFolder url="file://$MODULE_DIR$/acrate_database/tests" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/acrate_astreams/src" isTestSource="false" />
       <excludeFolder url="file://$MODULE_DIR$/target" />
     </content>
     <orderEntry type="inheritedJdk" />
     <orderEntry type="sourceFolder" forTests="false" />
   </component>
-</module>
\ No newline at end of file
+</module>
diff --git a/Cargo.toml b/Cargo.toml
index c4c058b..d8f27a3 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,3 +1,3 @@
 [workspace]
 resolver = "2"
-members = ["acrate_database", "acrate_rd", "acrate_nodeinfo", "acrate_rdserver", "acrate_apub_inbox"]
+members = ["acrate_database", "acrate_rd", "acrate_nodeinfo", "acrate_rdserver", "acrate_apub_inbox", "acrate_astreams"]
diff --git a/acrate_astreams/Cargo.toml b/acrate_astreams/Cargo.toml
new file mode 100644
index 0000000..733f628
--- /dev/null
+++ b/acrate_astreams/Cargo.toml
@@ -0,0 +1,17 @@
+[package]
+name = "acrate_astreams"
+version = "0.3.0"
+authors = ["Stefano Pigozzi <me@steffo.eu>"]
+edition = "2021"
+description = "ActivityStreams definitions and utilities"
+repository = "https://forge.steffo.eu/unimore/tirocinio-canali-steffo-acrate"
+license = "EUPL-1.2"
+keywords = ["activitypub", "activitystreams", "federation", "apub", "astreams"]
+categories = ["web-programming"]
+
+[dependencies]
+json-ld = { version = "0.21.1", features = ["serde", "reqwest"] }
+log = "0.4.22"
+serde = { version = "1.0.214", features = ["derive"] }
+serde_json = "1.0.132"
+thiserror = "2.0.3"
diff --git a/acrate_astreams/src/core.rs b/acrate_astreams/src/core.rs
new file mode 100644
index 0000000..96aca6d
--- /dev/null
+++ b/acrate_astreams/src/core.rs
@@ -0,0 +1,6 @@
+//! Struct definitions for ActivityStreams Core Types.
+//!
+//! # Specification
+//!
+//! - <https://www.w3.org/TR/activitystreams-vocabulary/#types>
+
diff --git a/acrate_astreams/src/extended.rs b/acrate_astreams/src/extended.rs
new file mode 100644
index 0000000..d5e2bb0
--- /dev/null
+++ b/acrate_astreams/src/extended.rs
@@ -0,0 +1,6 @@
+//! Struct definitions for ActivityStreams Extended Types.
+//!
+//! # Specification
+//!
+//! - <https://www.w3.org/TR/activitystreams-vocabulary/#extendedtypes>
+
diff --git a/acrate_astreams/src/lib.rs b/acrate_astreams/src/lib.rs
new file mode 100644
index 0000000..1db9975
--- /dev/null
+++ b/acrate_astreams/src/lib.rs
@@ -0,0 +1,11 @@
+//!
+//! # Specification
+//!
+//! - <https://www.w3.org/TR/activitystreams-vocabulary/>
+
+pub mod core;
+pub mod extended;
+
+pub mod mastodon;
+pub mod miajetzt;
+pub mod litepub;
diff --git a/acrate_astreams/src/litepub.rs b/acrate_astreams/src/litepub.rs
new file mode 100644
index 0000000..fa5755d
--- /dev/null
+++ b/acrate_astreams/src/litepub.rs
@@ -0,0 +1,6 @@
+//! Struct definitions for Pleroma and Akkoma's Extension Types.
+//!
+//! # Specification
+//!
+//! - <https://docs.akkoma.dev/develop/development/ap_extensions/>
+
diff --git a/acrate_astreams/src/mastodon.rs b/acrate_astreams/src/mastodon.rs
new file mode 100644
index 0000000..a410814
--- /dev/null
+++ b/acrate_astreams/src/mastodon.rs
@@ -0,0 +1,6 @@
+//! Struct definitions for Mastodon's Extension Types.
+//!
+//! # Specification
+//!
+//! - <https://docs.joinmastodon.org/spec/activitypub/#contexts>
+
diff --git a/acrate_astreams/src/miajetzt.rs b/acrate_astreams/src/miajetzt.rs
new file mode 100644
index 0000000..f1cf4af
--- /dev/null
+++ b/acrate_astreams/src/miajetzt.rs
@@ -0,0 +1,6 @@
+//! Struct definitions for mia's Extension Types.
+//!
+//! # Specification
+//!
+//! - <https://ns.mia.jetzt/as/>
+