diff --git a/crates/aiken-project/src/github/mod.rs b/crates/aiken-project/src/github/mod.rs
index c426b23eb..390aa570b 100644
--- a/crates/aiken-project/src/github/mod.rs
+++ b/crates/aiken-project/src/github/mod.rs
@@ -1 +1,2 @@
+pub mod payload;
 pub mod repo;
diff --git a/crates/aiken-project/src/github/payload/branch.rs b/crates/aiken-project/src/github/payload/branch.rs
new file mode 100644
index 000000000..ff720ef8b
--- /dev/null
+++ b/crates/aiken-project/src/github/payload/branch.rs
@@ -0,0 +1,8 @@
+use super::commit::Commit;
+use serde::Deserialize;
+
+#[derive(Deserialize)]
+pub struct Branch {
+    pub name: String,
+    pub commit: Commit,
+}
diff --git a/crates/aiken-project/src/github/payload/commit.rs b/crates/aiken-project/src/github/payload/commit.rs
new file mode 100644
index 000000000..6d7efb863
--- /dev/null
+++ b/crates/aiken-project/src/github/payload/commit.rs
@@ -0,0 +1,6 @@
+use serde::Deserialize;
+
+#[derive(Deserialize)]
+pub struct Commit {
+    pub sha: String,
+}
diff --git a/crates/aiken-project/src/github/payload/mod.rs b/crates/aiken-project/src/github/payload/mod.rs
new file mode 100644
index 000000000..b123361cd
--- /dev/null
+++ b/crates/aiken-project/src/github/payload/mod.rs
@@ -0,0 +1,5 @@
+pub mod branch;
+pub mod commit;
+pub mod release;
+pub mod repo;
+pub mod tag;
diff --git a/crates/aiken-project/src/github/payload/release.rs b/crates/aiken-project/src/github/payload/release.rs
new file mode 100644
index 000000000..e26d3647e
--- /dev/null
+++ b/crates/aiken-project/src/github/payload/release.rs
@@ -0,0 +1,6 @@
+use serde::Deserialize;
+
+#[derive(Deserialize)]
+pub struct Release {
+    pub tag_name: String,
+}
diff --git a/crates/aiken-project/src/github/payload/repo.rs b/crates/aiken-project/src/github/payload/repo.rs
new file mode 100644
index 000000000..18b86c77b
--- /dev/null
+++ b/crates/aiken-project/src/github/payload/repo.rs
@@ -0,0 +1,6 @@
+use serde::Deserialize;
+
+#[derive(Deserialize)]
+pub struct Repo {
+    pub default_branch: String,
+}
diff --git a/crates/aiken-project/src/github/payload/tag.rs b/crates/aiken-project/src/github/payload/tag.rs
new file mode 100644
index 000000000..a99548b4b
--- /dev/null
+++ b/crates/aiken-project/src/github/payload/tag.rs
@@ -0,0 +1,6 @@
+use serde::Deserialize;
+
+#[derive(Deserialize)]
+pub struct Tag {
+    pub name: String,
+}
diff --git a/crates/aiken-project/src/github/repo.rs b/crates/aiken-project/src/github/repo.rs
index e96c51102..28b7c94b1 100644
--- a/crates/aiken-project/src/github/repo.rs
+++ b/crates/aiken-project/src/github/repo.rs
@@ -1,22 +1,145 @@
-use reqwest::{blocking::Client, header::USER_AGENT, Error};
-use serde::Deserialize;
+use super::payload::{branch::Branch, release::Release, repo::Repo as RepoInfo, tag::Tag};
+use reqwest::{
+    blocking::{Client, Response},
+    header::USER_AGENT,
+    Error,
+};
+use std::time::Duration;
 
-#[derive(Deserialize)]
-pub struct LatestRelease {
-    pub tag_name: String,
+enum Get {
+    Releases,
+    Tags,
+    Branches,
+    Info,
 }
 
+enum Query<T> {
+    Param(T),
+    All,
+}
+
+const ALL: Query<String> = Query::All;
+
+// #region Github repo's RELEASES
+pub struct LatestRelease {}
 impl LatestRelease {
-    pub fn of<Repo: AsRef<str>>(repo: Repo) -> Result<Self, Error> {
-        Ok({
-            Client::new()
-                .get(format!(
-                    "https://api.github.com/repos/{}/releases/latest",
-                    repo.as_ref()
-                ))
-                .header(USER_AGENT, "aiken")
-                .send()?
-                .json::<Self>()?
-        })
+    pub fn of<Repo: AsRef<str>>(repo: Repo) -> Result<Release, Error> {
+        http_get(repo, Get::Releases, Query::Param("latest"))?.json::<Release>()
+    }
+}
+
+pub struct Releases {}
+impl Releases {
+    pub fn of<Repo: AsRef<str>>(repo: Repo) -> Result<Vec<Release>, Error> {
+        http_get(repo, Get::Releases, ALL)?.json::<Vec<Release>>()
+    }
+}
+// #endregion
+
+// #region Github repo's TAGS
+pub struct Tags {}
+impl Tags {
+    pub fn of<Repo: AsRef<str>>(repo: Repo) -> Result<Vec<Tag>, Error> {
+        http_get(repo, Get::Tags, ALL)?.json::<Vec<Tag>>()
+    }
+}
+// #endregion
+
+// #region Github repo's BRANCHES
+pub struct MainBranch {}
+impl MainBranch {
+    pub fn of<Repo: AsRef<str>>(repo: Repo) -> Result<Branch, Error> {
+        http_get(
+            repo,
+            Get::Branches,
+            Query::Param("master"), // Github will try to redirect this to `main`
+        )?
+        .json::<Branch>()
+    }
+}
+
+pub struct DefaultBranch {}
+impl DefaultBranch {
+    pub fn of<Repo: AsRef<str>>(repo: Repo) -> Result<Branch, Error> {
+        http_get(
+            &repo,
+            Get::Branches,
+            Query::Param(Info::of(&repo)?.default_branch),
+        )?
+        .json::<Branch>()
+    }
+}
+
+pub struct Branches {}
+impl Branches {
+    pub fn of<Repo: AsRef<str>>(repo: Repo) -> Result<Vec<Branch>, Error> {
+        http_get(repo, Get::Branches, ALL)?.json::<Vec<Branch>>()
+    }
+}
+// #endregion
+
+// #region Github repo's INFO
+pub struct Info {}
+impl Info {
+    pub fn of<Repo: AsRef<str>>(repo: Repo) -> Result<RepoInfo, Error> {
+        http_get(repo, Get::Info, ALL)?.json::<RepoInfo>()
+    }
+}
+// #endregion
+
+/// Sends an HTTP GET Request to Github API.
+///
+/// # Parameters
+///
+/// - `repo` must be in this format `owner/repo`.
+///   It accepts `str`, `String`, or `impl AsRef<str>`.
+///
+/// - `param` is used to query a certain `release`, `tag`, or `branch`.
+///
+/// # Example
+///
+/// `http_get("owner/repo", Get::Branches, Query::Param("branch_name"))`
+/// means it queries for the branch `branch_name`.
+fn http_get<Repo: AsRef<str>, Param: AsRef<str>>(
+    repo: Repo,
+    get: Get,
+    param: Query<Param>,
+) -> Result<Response, Error> {
+    let mut url = format!("https://api.github.com/repos/{}", repo.as_ref());
+    let path;
+    url.push_str(match get {
+        Get::Releases => {
+            path = format_path("/releases", param);
+            path.as_ref()
+        }
+        Get::Tags => {
+            path = match param {
+                Query::All => format_path("/tags", Query::All),
+                param => format_path("/releases/tags", param),
+            };
+            path.as_ref()
+        }
+        Get::Branches => {
+            path = format_path("/branches", param);
+            path.as_ref()
+        }
+        Get::Info => "",
+    });
+
+    Client::builder()
+        .timeout(Duration::from_secs(5)) // it's not cool waiting for too long
+        .build()?
+        .get(url)
+        .header(USER_AGENT, "aiken-lang")
+        .send()
+}
+
+fn format_path<Path: AsRef<str>, Param: AsRef<str>>(
+    path: Path,
+    param: Query<Param>,
+) -> impl AsRef<str> {
+    match param {
+        Query::Param(param) => format!("{}/{}", path.as_ref(), param.as_ref()),
+        _ => format!("{}", path.as_ref()),
     }
 }
diff --git a/crates/aiken/src/cmd/packages/add.rs b/crates/aiken/src/cmd/packages/add.rs
index c15e8f638..5d7b5a425 100644
--- a/crates/aiken/src/cmd/packages/add.rs
+++ b/crates/aiken/src/cmd/packages/add.rs
@@ -1,6 +1,7 @@
 use aiken_project::{
     config::{Config, Dependency, Platform},
     error::Warning,
+    github::repo::Info,
     package_name::PackageName,
     pretty,
 };
@@ -9,6 +10,7 @@ use owo_colors::{OwoColorize, Stream::Stderr};
 use std::{path::PathBuf, process, str::FromStr};
 
 #[derive(clap::Args)]
+#[clap(disable_version_flag = true)]
 /// Add a new project package as dependency
 pub struct Args {
     /// Package name, in the form of {owner}/{repository}.
@@ -20,7 +22,7 @@ pub struct Args {
     pub package: String,
     /// The package version, as a git commit hash, a tag or a branch name.
     #[clap(long)]
-    pub version: String,
+    pub version: Option<String>,
 
     #[clap(hide = true, long)]
     pub overwrite: bool,
@@ -31,7 +33,10 @@ pub fn exec(args: Args) -> miette::Result<()> {
 
     let dependency = Dependency {
         name: PackageName::from_str(&args.package)?,
-        version: args.version,
+        version: args.version.unwrap_or(match Info::of(&args.package) {
+            Ok(repo) => repo.default_branch,
+            _ => "main".to_string(),
+        }),
         source: Platform::Github,
     };
 
diff --git a/crates/aiken/src/cmd/packages/upgrade.rs b/crates/aiken/src/cmd/packages/upgrade.rs
index 4c6812014..5a4feee27 100644
--- a/crates/aiken/src/cmd/packages/upgrade.rs
+++ b/crates/aiken/src/cmd/packages/upgrade.rs
@@ -1,18 +1,19 @@
 use super::add;
 
 #[derive(clap::Args)]
+#[clap(disable_version_flag = true)]
 /// Change the version of an installed dependency
 pub struct Args {
     /// Package name, in the form of {owner}/{repository}.
     ///
-    /// For example → 'add aiken-lang/stdlib'
+    /// For example → 'packages upgrade aiken-lang/stdlib'
     ///
     /// Note that by default, this assumes the package is located
     /// on Github.
     package: String,
     /// The package version, as a git commit hash, a tag or a branch name.
     #[clap(long)]
-    version: String,
+    version: Option<String>,
 }
 
 pub fn exec(args: Args) -> miette::Result<()> {