diff --git a/local/recipes/system/cub/source/cub-cli/src/main.rs b/local/recipes/system/cub/source/cub-cli/src/main.rs
index a602cffe25..87a5b68870 100644
--- a/local/recipes/system/cub/source/cub-cli/src/main.rs
+++ b/local/recipes/system/cub/source/cub-cli/src/main.rs
@@ -839,12 +839,46 @@ fn build_dep_graph(
     Ok(plan)
 }
 
+fn check_version_constraint(dep: &str) {
+    if let Some((name, req)) = cub::version::parse_constraint(dep) {
+        if let Some(installed) = read_installed_version(&name) {
+            if !req.matches(&installed) {
+                eprintln!(
+                    "    warning: {name} constraint {} not satisfied by installed version {installed}",
+                    req
+                );
+            }
+        }
+    }
+}
+
+fn read_installed_version(pkg: &str) -> Option<cub::version::Version> {
+    let canonical = pkg.trim_start_matches("host:").to_ascii_lowercase();
+    let path = format!("/var/lib/pkg/lib/{canonical}/info");
+    let content = std::fs::read_to_string(&path).ok()?;
+    for line in content.lines() {
+        if let Some((key, value)) = line.split_once('=') {
+            if key.trim() == "version" {
+                return cub::version::Version::parse(value.trim());
+            }
+        }
+    }
+    None
+}
+
 fn install_one_dep(
     context: &AppContext,
     library: &mut Library,
-    dep: &str,
+    raw_dep: &str,
 ) -> Result<(), Box<dyn std::error::Error>> {
-    let package_name = match PackageName::new(dep.to_string()) {
+    let dep = cub::deps::dependency_base_name(raw_dep);
+    if dep.is_empty() {
+        eprintln!("  skipping empty dep after stripping constraint: {raw_dep}");
+        return Ok(());
+    }
+    check_version_constraint(raw_dep);
+
+    let package_name = match PackageName::new(dep.clone()) {
         Ok(name) => name,
         Err(_) => {
             eprintln!("  skipping invalid package name: {dep}");
@@ -871,7 +905,7 @@ fn install_one_dep(
 
     print!("    fetching {dep} from AUR... ");
     io::stdout().flush()?;
-    match fetch_aur_to_store(dep) {
+    match fetch_aur_to_store(&dep) {
         Ok(_) => println!("done (recipe at ~/.cub/recipes/{dep}/)"),
         Err(error) => println!("failed: {error}"),
     }
diff --git a/local/recipes/system/cub/source/cub-lib/src/depgraph.rs b/local/recipes/system/cub/source/cub-lib/src/depgraph.rs
index 800a24ab8e..902d8abde7 100644
--- a/local/recipes/system/cub/source/cub-lib/src/depgraph.rs
+++ b/local/recipes/system/cub/source/cub-lib/src/depgraph.rs
@@ -4,9 +4,18 @@ use crate::aur::AurPackage;
 use crate::depresolve::{DepNode, resolve_build_order};
 use crate::deps::dependency_base_name;
 
+fn display_name_key(name: &str) -> String {
+    name.trim_start_matches("host:").to_ascii_lowercase()
+}
+
 pub struct ResolvedInstallPlan {
     pub build_order: Vec<String>,
     pub circular: Vec<Vec<String>>,
+    /// Map from canonical package name to a comma-separated list of
+    /// version constraints the build order honours (e.g. "openssl>=1.1").
+    /// Populated only when AUR info was available; missing for offline
+    /// or unknown packages.
+    pub version_constraints: std::collections::HashMap<String, Vec<String>>,
 }
 
 pub struct DepGraphBuilder<'a> {
@@ -45,6 +54,9 @@ impl<'a> DepGraphBuilder<'a> {
     }
 
     pub fn build(mut self) -> ResolvedInstallPlan {
+        let mut version_constraints: std::collections::HashMap<String, Vec<String>> =
+            std::collections::HashMap::new();
+
         while let Some(name) = self.queue.pop_front() {
             let normalized = name.to_ascii_lowercase();
             if !self.seen.insert(normalized.clone()) {
@@ -56,7 +68,7 @@ impl<'a> DepGraphBuilder<'a> {
 
             let pkg = (self.fetch)(&name);
 
-            let (depends, makedepends, provides, display_name) = match pkg {
+            let (depends, makedepends, provides, display_name, raw_constraints) = match pkg {
                 Some(pkg) => {
                     let depends: Vec<String> = pkg
                         .depends
@@ -70,10 +82,28 @@ impl<'a> DepGraphBuilder<'a> {
                         .map(|d| dependency_base_name(d).to_string())
                         .filter(|d| !d.is_empty())
                         .collect();
+                    let raw_constraints: Vec<String> = pkg
+                        .depends
+                        .iter()
+                        .chain(pkg.makedepends.iter())
+                        .filter(|d| dependency_base_name(d) == display_name_key(&pkg.name))
+                        .chain(
+                            pkg.depends
+                                .iter()
+                                .chain(pkg.makedepends.iter())
+                                .filter(|d| {
+                                    let base = dependency_base_name(d);
+                                    !base.is_empty()
+                                        && depends.contains(&base.to_string())
+                                        || makedepends.contains(&base.to_string())
+                                }),
+                        )
+                        .cloned()
+                        .collect();
                     let name = pkg.name.clone();
-                    (depends, makedepends, pkg.provides.clone(), name)
+                    (depends, makedepends, pkg.provides.clone(), name, raw_constraints)
                 }
-                None => (Vec::new(), Vec::new(), Vec::new(), name),
+                None => (Vec::new(), Vec::new(), Vec::new(), name, Vec::new()),
             };
 
             for transitive in depends.iter().chain(makedepends.iter()) {
@@ -83,6 +113,15 @@ impl<'a> DepGraphBuilder<'a> {
                 }
             }
 
+            for raw in &raw_constraints {
+                if let Some((base, _)) = crate::version::parse_constraint(raw) {
+                    let key = base.trim_start_matches("host:").to_ascii_lowercase();
+                    if !key.is_empty() {
+                        version_constraints.entry(key).or_default().push(raw.clone());
+                    }
+                }
+            }
+
             self.nodes.push(DepNode {
                 name: display_name,
                 depends,
@@ -95,6 +134,7 @@ impl<'a> DepGraphBuilder<'a> {
         ResolvedInstallPlan {
             build_order: resolved.build_order,
             circular: resolved.circular,
+            version_constraints,
         }
     }
 }
@@ -202,4 +242,18 @@ mod tests {
         assert!(pos("b") < pos("a"));
         assert!(pos("c") < pos("a"));
     }
+
+    #[test]
+    fn version_constraints_preserved_on_dependents() {
+        let packages = vec![
+            aur_pkg("a", &["b>=1.0"], &[], &[]),
+            aur_pkg("b", &[], &[], &[]),
+        ];
+        let installed = HashSet::new();
+        let plan = DepGraphBuilder::with_fetcher(["a"], &installed, fetch_one(&packages)).build();
+        assert_eq!(
+            plan.version_constraints.get("b"),
+            Some(&vec!["b>=1.0".to_string()])
+        );
+    }
 }
diff --git a/local/recipes/system/cub/source/cub-lib/src/lib.rs b/local/recipes/system/cub/source/cub-lib/src/lib.rs
index 884bf55d1a..35471c53cd 100644
--- a/local/recipes/system/cub/source/cub-lib/src/lib.rs
+++ b/local/recipes/system/cub/source/cub-lib/src/lib.rs
@@ -15,5 +15,6 @@ pub mod recipe;
 pub mod resolver;
 pub mod sandbox;
 pub mod storage;
+pub mod version;
 
 pub use error::CubError;
diff --git a/local/recipes/system/cub/source/cub-lib/src/version.rs b/local/recipes/system/cub/source/cub-lib/src/version.rs
new file mode 100644
index 0000000000..c64e85223d
--- /dev/null
+++ b/local/recipes/system/cub/source/cub-lib/src/version.rs
@@ -0,0 +1,318 @@
+use std::cmp::Ordering;
+use std::fmt;
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct VersionReq {
+    pub comparator: Comparator,
+    pub version: Version,
+    /// A second clause for ranges (e.g. `>=1.0,<2.0`). Only `&&` chaining
+    /// is supported (no `||`).
+    pub second: Option<(Comparator, Version)>,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum Comparator {
+    Eq,
+    Lt,
+    Le,
+    Gt,
+    Ge,
+}
+
+impl Comparator {
+    fn parse(s: &str) -> Option<(Self, &str)> {
+        let chars: Vec<char> = s.chars().collect();
+        if chars.len() < 2 {
+            return None;
+        }
+        let (op, rest) = match (chars[0], chars[1]) {
+            ('=', _) => (Comparator::Eq, &s[1..]),
+            ('<', '=') => (Comparator::Le, &s[2..]),
+            ('<', _) => (Comparator::Lt, &s[1..]),
+            ('>', '=') => (Comparator::Ge, &s[2..]),
+            ('>', _) => (Comparator::Gt, &s[1..]),
+            _ => return None,
+        };
+        Some((op, rest.trim_start()))
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct Version {
+    pub parts: Vec<u64>,
+    pub suffix: Option<String>,
+    pub revision: Option<u64>,
+}
+
+impl Version {
+    pub fn parse(s: &str) -> Option<Self> {
+        let s = s.trim();
+        if s.is_empty() {
+            return None;
+        }
+        let (base, revision) = match s.split_once('-') {
+            Some((b, r)) if r.chars().next().map_or(false, |c| c.is_ascii_digit()) => {
+                (b, Some(r.parse().ok()?))
+            }
+            _ => (s, None),
+        };
+        let (core, suffix) = match base.find(|c: char| !c.is_ascii_digit() && c != '.') {
+            Some(i) => (Some(&base[..i]), Some(base[i..].to_string())),
+            None => (Some(base), None),
+        };
+        let parts: Vec<u64> = core?
+            .split('.')
+            .map(|p| p.parse::<u64>().ok())
+            .collect::<Option<_>>()?;
+        Some(Version {
+            parts,
+            suffix,
+            revision,
+        })
+    }
+
+    pub fn satisfies(&self, op: &Comparator, target: &Version) -> bool {
+        let cmp = self.cmp(target);
+        match op {
+            Comparator::Eq => cmp == Ordering::Equal,
+            Comparator::Lt => cmp == Ordering::Less,
+            Comparator::Le => cmp == Ordering::Less || cmp == Ordering::Equal,
+            Comparator::Gt => cmp == Ordering::Greater,
+            Comparator::Ge => cmp == Ordering::Greater || cmp == Ordering::Equal,
+        }
+    }
+}
+
+impl PartialOrd for Version {
+    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+        Some(self.cmp(other))
+    }
+}
+
+impl Ord for Version {
+    fn cmp(&self, other: &Self) -> Ordering {
+        let max = self.parts.len().max(other.parts.len());
+        for i in 0..max {
+            let a = self.parts.get(i).copied().unwrap_or(0);
+            let b = other.parts.get(i).copied().unwrap_or(0);
+            match a.cmp(&b) {
+                Ordering::Equal => continue,
+                ord => return ord,
+            }
+        }
+        let sa = self.suffix.as_deref().unwrap_or("");
+        let sb = other.suffix.as_deref().unwrap_or("");
+        if sa != sb {
+            return sa.cmp(sb);
+        }
+        self.revision.cmp(&other.revision)
+    }
+}
+
+impl fmt::Display for Version {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{}", self.parts.iter().map(u64::to_string).collect::<Vec<_>>().join("."))?;
+        if let Some(suffix) = &self.suffix {
+            write!(f, "{suffix}")?;
+        }
+        if let Some(rev) = self.revision {
+            write!(f, "-{rev}")?;
+        }
+        Ok(())
+    }
+}
+
+impl VersionReq {
+    pub fn parse(s: &str) -> Option<Self> {
+        let s = s.trim();
+        if s.is_empty() {
+            return None;
+        }
+        let mut parts = s.split(',');
+        let first = parts.next()?.trim();
+        let (op, rest) = Comparator::parse(first)?;
+        let version = Version::parse(rest)?;
+
+        let second = if let Some(second_raw) = parts.next() {
+            if parts.next().is_some() {
+                return None;
+            }
+            let (op2, rest2) = Comparator::parse(second_raw.trim())?;
+            let version2 = Version::parse(rest2)?;
+            Some((op2, version2))
+        } else {
+            None
+        };
+
+        Some(VersionReq {
+            comparator: op,
+            version,
+            second,
+        })
+    }
+
+    pub fn matches(&self, candidate: &Version) -> bool {
+        if !candidate.satisfies(&self.comparator, &self.version) {
+            return false;
+        }
+        if let Some((op, version)) = &self.second {
+            if !candidate.satisfies(op, version) {
+                return false;
+            }
+        }
+        true
+    }
+}
+
+impl fmt::Display for VersionReq {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let op = match self.comparator {
+            Comparator::Eq => "=",
+            Comparator::Lt => "<",
+            Comparator::Le => "<=",
+            Comparator::Gt => ">",
+            Comparator::Ge => ">=",
+        };
+        write!(f, "{op}{}", self.version)?;
+        if let Some((op, v)) = &self.second {
+            let op = match op {
+                Comparator::Eq => "=",
+                Comparator::Lt => "<",
+                Comparator::Le => "<=",
+                Comparator::Gt => ">",
+                Comparator::Ge => ">=",
+            };
+            write!(f, ",{op}{v}")?;
+        }
+        Ok(())
+    }
+}
+
+pub fn parse_constraint(s: &str) -> Option<(String, VersionReq)> {
+    let (base, rest) = s.split_once(|c: char| matches!(c, '<' | '>' | '='))?;
+    let base = base.trim().to_string();
+    let req = VersionReq::parse(rest)?;
+    Some((base, req))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn v(s: &str) -> Version {
+        Version::parse(s).expect(s)
+    }
+
+    fn r(s: &str) -> VersionReq {
+        VersionReq::parse(s).expect(s)
+    }
+
+    #[test]
+    fn parses_semver_version() {
+        let v = v("1.2.3");
+        assert_eq!(v.parts, vec![1, 2, 3]);
+        assert_eq!(v.revision, None);
+    }
+
+    #[test]
+    fn parses_arch_date_based_version() {
+        let v = v("1.2.3-1");
+        assert_eq!(v.parts, vec![1, 2, 3]);
+        assert_eq!(v.revision, Some(1));
+    }
+
+    #[test]
+    fn parses_version_with_alpha_suffix() {
+        let v = v("1.2.3rc1");
+        assert_eq!(v.parts, vec![1, 2, 3]);
+        assert_eq!(v.suffix.as_deref(), Some("rc1"));
+    }
+
+    #[test]
+    fn versions_compare_lexically_on_parts() {
+        assert!(v("1.2.3") < v("1.2.4"));
+        assert!(v("1.2.10") > v("1.2.9"));
+        assert_eq!(v("1.2.3").cmp(&v("1.2.3")), Ordering::Equal);
+    }
+
+    #[test]
+    fn shorter_version_treats_missing_parts_as_zero() {
+        assert!(v("1.2") < v("1.2.1"));
+        assert_eq!(v("1.0").cmp(&v("1.0.0")), Ordering::Equal);
+    }
+
+    #[test]
+    fn arch_pkgrel_breaks_ties() {
+        assert!(v("1.2.3-1") < v("1.2.3-2"));
+    }
+
+    #[test]
+    fn equality_constraint() {
+        let req = r("=1.2.3");
+        assert!(req.matches(&v("1.2.3")));
+        assert!(!req.matches(&v("1.2.4")));
+    }
+
+    #[test]
+    fn greater_than_constraint() {
+        let req = r(">=1.0");
+        assert!(req.matches(&v("1.0.0")));
+        assert!(req.matches(&v("2.0.0")));
+        assert!(!req.matches(&v("0.9.0")));
+    }
+
+    #[test]
+    fn less_than_constraint() {
+        let req = r("<2.0");
+        assert!(req.matches(&v("1.9.9")));
+        assert!(!req.matches(&v("2.0.0")));
+        assert!(!req.matches(&v("2.0")));
+    }
+
+    #[test]
+    fn less_than_or_equal_constraint() {
+        let req = r("<=2.0");
+        assert!(req.matches(&v("2.0.0")));
+        assert!(req.matches(&v("1.5.0")));
+        assert!(!req.matches(&v("2.0.1")));
+    }
+
+    #[test]
+    fn range_constraint() {
+        let req = r(">=1.0,<2.0");
+        assert!(req.matches(&v("1.0.0")));
+        assert!(req.matches(&v("1.5.7")));
+        assert!(!req.matches(&v("2.0.0")));
+        assert!(!req.matches(&v("0.9.9")));
+    }
+
+    #[test]
+    fn arch_pkgrel_constraint() {
+        let req = r(">=1.2.3-1");
+        assert!(req.matches(&v("1.2.3-1")));
+        assert!(req.matches(&v("1.2.3-2")));
+        assert!(!req.matches(&v("1.2.3")));
+    }
+
+    #[test]
+    fn mixed_semver_and_arch_versions() {
+        let req = r(">=1.0");
+        assert!(req.matches(&v("1.0.0-1")));
+        assert!(req.matches(&v("1.0")));
+    }
+
+    #[test]
+    fn parses_constraint_with_name() {
+        let (name, req) = parse_constraint("openssl>=1.1").expect("parse");
+        assert_eq!(name, "openssl");
+        assert!(req.matches(&v("1.1.0")));
+        assert!(!req.matches(&v("1.0.0")));
+    }
+
+    #[test]
+    fn rejects_invalid_constraint_syntax() {
+        assert!(VersionReq::parse("not-a-version").is_none());
+        assert!(VersionReq::parse(">=").is_none());
+        assert!(VersionReq::parse(">1.0,<2.0,extra").is_none());
+    }
+}