diff --git a/src/analyzer/display.rs b/src/analyzer/display.rs
new file mode 100644
index 000000000..0d7e7f385
--- /dev/null
+++ b/src/analyzer/display.rs
@@ -0,0 +1,75 @@
+use std::fmt::{Display, Formatter, Result};
+
+use super::*;
+
+impl Display for Identity {
+    fn fmt(&self, f: &mut Formatter<'_>) -> Result {
+        match self.kind {
+            IdentityKind::Polynomial => {
+                let expression = self.left.selector.as_ref().unwrap();
+                if let Expression::BinaryOperation(left, BinaryOperator::Sub, right) = expression {
+                    write!(f, "{left} = {right};")
+                } else {
+                    write!(f, "{expression} = 0;")
+                }
+            }
+            IdentityKind::Plookup => write!(f, "{} in {};", self.left, self.right),
+            IdentityKind::Permutation => write!(f, "{} is {};", self.left, self.right),
+            IdentityKind::Connect => write!(f, "{} connect {};", self.left, self.right),
+        }
+    }
+}
+
+impl Display for SelectedExpressions {
+    fn fmt(&self, f: &mut Formatter<'_>) -> Result {
+        write!(
+            f,
+            "{}{{ {} }}",
+            self.selector
+                .as_ref()
+                .map(|s| format!("{s} "))
+                .unwrap_or_default(),
+            format_expressions(&self.expressions)
+        )
+    }
+}
+
+impl Display for Expression {
+    fn fmt(&self, f: &mut Formatter<'_>) -> Result {
+        match self {
+            Expression::Constant(name) => write!(f, "{name}"),
+            Expression::PolynomialReference(reference) => write!(f, "{reference}"),
+            Expression::PublicReference(name) => write!(f, "{name}"),
+            Expression::Number(value) => write!(f, "{value}"),
+            Expression::String(value) => write!(f, "\"{value}\""), // TODO quote?
+            Expression::Tuple(items) => write!(f, "({})", format_expressions(items)),
+            Expression::BinaryOperation(left, op, right) => write!(f, "({left} {op} {right})"),
+            Expression::UnaryOperation(op, exp) => write!(f, "{op}{exp}"),
+            Expression::FunctionCall(fun, args) => write!(f, "{fun}({})", format_expressions(args)),
+            Expression::LocalVariableReference(index) => write!(f, "${index}"),
+        }
+    }
+}
+
+fn format_expressions(expressions: &[Expression]) -> String {
+    expressions
+        .iter()
+        .map(|e| format!("{e}"))
+        .collect::<Vec<_>>()
+        .join(", ")
+}
+
+impl Display for PolynomialReference {
+    fn fmt(&self, f: &mut Formatter<'_>) -> Result {
+        write!(
+            f,
+            "{}{}{}",
+            self.name,
+            self.index
+                .as_ref()
+                .map(|s| format!("[{s}]"))
+                .unwrap_or_default(),
+            if self.next { "'" } else { "" }
+        )
+    }
+}
diff --git a/src/analyzer/mod.rs b/src/analyzer/mod.rs
index d7f463e0a..bd958bcda 100644
--- a/src/analyzer/mod.rs
+++ b/src/analyzer/mod.rs
@@ -1,3 +1,4 @@
+pub mod display;
 pub mod pil_analyzer;
 
 use std::collections::HashMap;
diff --git a/src/commit_evaluator/mod.rs b/src/commit_evaluator/mod.rs
index d7329b592..cd2516605 100644
--- a/src/commit_evaluator/mod.rs
+++ b/src/commit_evaluator/mod.rs
@@ -148,7 +148,8 @@ where
                     }
                     IdentityKind::Plookup => self.process_plookup(identity),
                     _ => Ok(vec![]),
-                };
+                }
+                .map_err(|err| format!("No progress on {identity}:\n    {err}"));
                 self.handle_eval_result(result);
             }
             if !self.progress {
@@ -543,6 +544,7 @@ where
         e.coefficients
             .iter()
             .enumerate()
+            .filter(|(_, &c)| c != 0)
             .map(|(i, c)| format!("{} * {c}", self.committed_names[i]))
             .chain(e.constant_value().map(|v| format!("{v}")))
             .collect::<Vec<_>>()