diff --git a/crates/simplexpr/src/ast.rs b/crates/simplexpr/src/ast.rs
index 4b56cfb..4edf00b 100644
--- a/crates/simplexpr/src/ast.rs
+++ b/crates/simplexpr/src/ast.rs
@@ -17,6 +17,8 @@ pub enum BinOp {
     #[strum(serialize = "!=")] NotEquals,
     #[strum(serialize = "&&")] And,
     #[strum(serialize = "||")] Or,
+    #[strum(serialize = ">=") ] GE,
+    #[strum(serialize = "<=") ] LE,
     #[strum(serialize = ">") ] GT,
     #[strum(serialize = "<") ] LT,
     #[strum(serialize = "?:")] Elvis,
@@ -27,6 +29,8 @@ pub enum BinOp {
 pub enum UnaryOp {
     #[strum(serialize = "!")]
     Not,
+    #[strum(serialize = "-")]
+    Negative,
 }
 
 #[derive(Clone, PartialEq, Eq, Serialize, Deserialize)]
diff --git a/crates/simplexpr/src/eval.rs b/crates/simplexpr/src/eval.rs
index a3f1789..910dbb7 100644
--- a/crates/simplexpr/src/eval.rs
+++ b/crates/simplexpr/src/eval.rs
@@ -190,6 +190,8 @@ impl SimplExpr {
                     BinOp::Mod => DynVal::from(a.as_f64()? % b.as_f64()?),
                     BinOp::GT => DynVal::from(a.as_f64()? > b.as_f64()?),
                     BinOp::LT => DynVal::from(a.as_f64()? < b.as_f64()?),
+                    BinOp::GE => DynVal::from(a.as_f64()? >= b.as_f64()?),
+                    BinOp::LE => DynVal::from(a.as_f64()? <= b.as_f64()?),
                     #[allow(clippy::useless_conversion)]
                     BinOp::Elvis => DynVal::from(if a.0.is_empty() { b } else { a }),
                     BinOp::RegexMatch => {
@@ -203,6 +205,7 @@ impl SimplExpr {
                 let a = a.eval(values)?;
                 Ok(match op {
                     UnaryOp::Not => DynVal::from(!a.as_bool()?).at(*span),
+                    UnaryOp::Negative => DynVal::from(-a.as_f64()?).at(*span),
                 })
             }
             SimplExpr::IfElse(_, cond, yes, no) => {
diff --git a/crates/simplexpr/src/parser/lexer.rs b/crates/simplexpr/src/parser/lexer.rs
index e7a4ce0..36e2418 100644
--- a/crates/simplexpr/src/parser/lexer.rs
+++ b/crates/simplexpr/src/parser/lexer.rs
@@ -23,12 +23,15 @@ pub enum Token {
     NotEquals,
     And,
     Or,
+    GE,
+    LE,
     GT,
     LT,
     Elvis,
     RegexMatch,
 
     Not,
+    Negative,
 
     Comma,
     Question,
@@ -80,12 +83,15 @@ regex_rules! {
     escape(r"!=")    => |_| Token::NotEquals,
     escape(r"&&")    => |_| Token::And,
     escape(r"||")    => |_| Token::Or,
+    escape(r">=")    => |_| Token::GE,
+    escape(r"<=")    => |_| Token::LE,
     escape(r">")     => |_| Token::GT,
     escape(r"<")     => |_| Token::LT,
     escape(r"?:")    => |_| Token::Elvis,
     escape(r"=~")    => |_| Token::RegexMatch,
 
     escape(r"!" )    => |_| Token::Not,
+    escape(r"-" )    => |_| Token::Negative,
 
     escape(r",")     => |_| Token::Comma,
     escape(r"?")     => |_| Token::Question,
diff --git a/crates/simplexpr/src/simplexpr_parser.lalrpop b/crates/simplexpr/src/simplexpr_parser.lalrpop
index fd4d1f7..c63a644 100644
--- a/crates/simplexpr/src/simplexpr_parser.lalrpop
+++ b/crates/simplexpr/src/simplexpr_parser.lalrpop
@@ -20,6 +20,8 @@ extern {
     "!=" => Token::NotEquals,
     "&&" => Token::And,
     "||" => Token::Or,
+    ">=" => Token::GE,
+    "<=" => Token::LE,
     ">"  => Token::GT,
     "<"  => Token::LT,
     "?:" => Token::Elvis,
@@ -81,6 +83,7 @@ pub Expr: SimplExpr = {
 
   #[precedence(level="2")] #[assoc(side="right")]
   <l:@L> "!" <e:Expr> <r:@R> => UnaryOp(Span(l, r, fid), Not, b(e)),
+  <l:@L> "-" <e:Expr> <r:@R> => UnaryOp(Span(l, r, fid), Negative, b(e)),
 
   #[precedence(level="3")] #[assoc(side="left")]
   <l:@L> <le:Expr> "*"  <re:Expr> <r:@R> => BinOp(Span(l, r, fid), b(le), Times,       b(re)),
@@ -94,6 +97,8 @@ pub Expr: SimplExpr = {
   #[precedence(level="5")] #[assoc(side="left")]
   <l:@L> <le:Expr> "==" <re:Expr> <r:@R> => BinOp(Span(l, r, fid), b(le), Equals,     b(re)),
   <l:@L> <le:Expr> "!=" <re:Expr> <r:@R> => BinOp(Span(l, r, fid), b(le), NotEquals,  b(re)),
+  <l:@L> <le:Expr> ">=" <re:Expr> <r:@R> => BinOp(Span(l, r, fid), b(le), GE,         b(re)),
+  <l:@L> <le:Expr> "<=" <re:Expr> <r:@R> => BinOp(Span(l, r, fid), b(le), LE,         b(re)),
   <l:@L> <le:Expr> ">"  <re:Expr> <r:@R> => BinOp(Span(l, r, fid), b(le), GT,         b(re)),
   <l:@L> <le:Expr> "<"  <re:Expr> <r:@R> => BinOp(Span(l, r, fid), b(le), LT,         b(re)),
   <l:@L> <le:Expr> "=~" <re:Expr> <r:@R> => BinOp(Span(l, r, fid), b(le), RegexMatch, b(re)),
diff --git a/docs/src/expression_language.md b/docs/src/expression_language.md
index 6b051ce..a98daf3 100644
--- a/docs/src/expression_language.md
+++ b/docs/src/expression_language.md
@@ -21,7 +21,7 @@ as well as within strings, inside string-interpolation blocks (`"foo ${ ... } ba
 
 Supported currently are the following features:
 - simple mathematical operations (`+`, `-`, `*`, `/`, `%`)
-- comparisons (`==`, `!=`, `>`, `<`)
+- comparisons (`==`, `!=`, `>`, `<`, `<=`, `>=`)
 - boolean operations (`||`, `&&`, `!`)
 - elvis operator (`?:`)
     - if the left side is `""`, then returns the right side, otherwise evaluates to the left side.