diff --git a/src/flow/src/compute/plan/mod.rs b/src/flow/src/compute/plan/mod.rs
index 9e42000891..41705504a0 100644
--- a/src/flow/src/compute/plan/mod.rs
+++ b/src/flow/src/compute/plan/mod.rs
@@ -4,7 +4,9 @@ mod reduce;
 use std::collections::BTreeMap;
 
 use join::JoinPlan;
-pub(crate) use reduce::{convert_indexes_to_skips, AccumulablePlan, KeyValPlan, ReducePlan, BucketedPlan};
+pub(crate) use reduce::{
+    convert_indexes_to_skips, AccumulablePlan, BucketedPlan, KeyValPlan, ReducePlan,
+};
 use serde::{Deserialize, Serialize};
 
 use crate::expr::{Id, LocalId, MapFilterProject, ScalarExpr, TableFunc};
@@ -217,4 +219,4 @@ fn bucketing_of_expected_group_size(expected_group_size: Option<u64>) -> Vec<u64
 
     buckets.reverse();
     buckets
-}
\ No newline at end of file
+}
diff --git a/src/flow/src/compute/render/error.rs b/src/flow/src/compute/render/error.rs
index 8b9ff93054..cf0736fe1e 100644
--- a/src/flow/src/compute/render/error.rs
+++ b/src/flow/src/compute/render/error.rs
@@ -1,12 +1,13 @@
-use differential_dataflow::ExchangeData;
 use std::hash::Hash;
 
+use differential_dataflow::ExchangeData;
+
 use crate::repr::Row;
 
 /// Used to make possibly-validating code generic: think of this as a kind of `MaybeResult`,
 /// specialized for use in compute.  Validation code will only run when the error constructor is
 /// Some.
-pub(super) trait MaybeValidatingRow<T, E>: ExchangeData +  Hash {
+pub(super) trait MaybeValidatingRow<T, E>: ExchangeData + Hash {
     fn ok(t: T) -> Self;
     fn into_error() -> Option<fn(E) -> Self>;
 }
diff --git a/src/flow/src/compute/render/mod.rs b/src/flow/src/compute/render/mod.rs
index a4ddfa6fa8..6e379626cf 100644
--- a/src/flow/src/compute/render/mod.rs
+++ b/src/flow/src/compute/render/mod.rs
@@ -21,8 +21,8 @@ use crate::expr::Id;
 use crate::repr::{self, Row};
 use crate::storage::errors::DataflowError;
 
-mod reduce;
 mod error;
+mod reduce;
 
 /// Assemble the "compute"  side of a dataflow, i.e. all but the sources.
 ///
diff --git a/src/flow/src/expr/relation/func.rs b/src/flow/src/expr/relation/func.rs
index 074b0e6e61..039c857dbe 100644
--- a/src/flow/src/expr/relation/func.rs
+++ b/src/flow/src/expr/relation/func.rs
@@ -1,4 +1,5 @@
-use datatypes::value::Value;
+use datatypes::prelude::ConcreteDataType;
+use datatypes::value::{OrderedF32, OrderedF64, Value};
 use serde::{Deserialize, Serialize};
 
 #[derive(Clone, Debug, Eq, PartialEq, Ord, PartialOrd, Serialize, Deserialize, Hash)]
@@ -43,8 +44,50 @@ pub enum AggregateFunc {
 }
 
 impl AggregateFunc {
-    pub fn eval<I>(&self, values: I)->Value
-    where I: IntoIterator<Item = Value>{
-        todo!()
+    pub fn eval<I>(&self, values: I) -> Value
+    where
+        I: IntoIterator<Item = Value>,
+    {
+        match self {
+            AggregateFunc::MaxInt16 => max_value::<I, i16>(values),
+            AggregateFunc::MaxInt32 => max_value::<I, i32>(values),
+            AggregateFunc::MaxInt64 => max_value::<I, i64>(values),
+            AggregateFunc::MaxUInt16 => max_value::<I, u16>(values),
+            AggregateFunc::MaxUInt32 => max_value::<I, u32>(values),
+            AggregateFunc::MaxUInt64 => max_value::<I, u64>(values),
+            AggregateFunc::MaxFloat32 => max_value::<I, OrderedF32>(values),
+            AggregateFunc::MaxFloat64 => max_value::<I, OrderedF64>(values),
+            _ => todo!(),
+        }
     }
 }
+
+fn max_value<I, TypedValue>(values: I) -> Value
+where
+    I: IntoIterator<Item = Value>,
+    TypedValue: TryFrom<Value> + Ord,
+    <TypedValue as TryFrom<Value>>::Error: std::fmt::Debug,
+    Value: From<Option<TypedValue>>,
+{
+    let x: Option<TypedValue> = values
+        .into_iter()
+        .filter(|v| !v.is_null())
+        .map(|v| TypedValue::try_from(v).expect("unexpected type"))
+        .max();
+    x.into()
+}
+
+fn min_value<I, TypedValue>(values: I) -> Value
+where
+    I: IntoIterator<Item = Value>,
+    TypedValue: TryFrom<Value> + Ord,
+    <TypedValue as TryFrom<Value>>::Error: std::fmt::Debug,
+    Value: From<Option<TypedValue>>,
+{
+    let x: Option<TypedValue> = values
+        .into_iter()
+        .filter(|v| !v.is_null())
+        .map(|v| TypedValue::try_from(v).expect("unexpected type"))
+        .min();
+    x.into()
+}