diff --git a/.github/workflows/nightly-fuzz-test.yml b/.github/workflows/nightly-fuzz-test.yml
index 2c05f711289..a1560d52d14 100644
--- a/.github/workflows/nightly-fuzz-test.yml
+++ b/.github/workflows/nightly-fuzz-test.yml
@@ -16,8 +16,8 @@ env:
   # On regular PRs we run deterministic fuzzing to avoid flaky tests on CI.
   # In the nightly tests we want to explore uncharted territory.
   NOIR_AST_FUZZER_FORCE_NON_DETERMINISTIC: 1
-  # Tell arbtest how long it can run the tests for.
-  NOIR_AST_FUZZER_FORCE_BUDGET_SECS: 300
+  # How long should we run the fuzzing for, in seconds.
+  NOIR_AST_FUZZER_BUDGET_SECS: 300
 
 jobs:
   ast-fuzz:
diff --git a/TESTING.md b/TESTING.md
index a758ea610d8..e7ded32a0c3 100644
--- a/TESTING.md
+++ b/TESTING.md
@@ -104,7 +104,7 @@ cargo test -p noir_ast_fuzzer_fuzz arbtest
 Should it find any problems, the test would print a _seed_ which we can use to replicate the test, for example:
 
 ```shell
-NOIR_ARBTEST_SEED=0x6819c61400001000 cargo test -p noir_ast_fuzzer_fuzz comptime_vs_brillig
+NOIR_AST_FUZZER_SEED=0x6819c61400001000 cargo test -p noir_ast_fuzzer_fuzz comptime_vs_brillig
 ```
 
-When the `NOIR_ARBTEST_SEED` is present, or when there is a non-panicky error, the tests will print out the Noir AST and the `Prover.toml` file which can be used to reproduce the problem as an integration test.
+When the `NOIR_AST_FUZZER_SEED` is present, or when there is a non-panicky error, the tests will print out the Noir AST and the `Prover.toml` file which can be used to reproduce the problem as an integration test.
diff --git a/tooling/ast_fuzzer/README.md b/tooling/ast_fuzzer/README.md
index 4c4f481e3c0..26ef2669f7f 100644
--- a/tooling/ast_fuzzer/README.md
+++ b/tooling/ast_fuzzer/README.md
@@ -48,7 +48,7 @@ To get quick feedback about whether there are any easy-to-discover bugs, we can
 cargo test -p noir_ast_fuzzer_fuzz arbtest
 ```
 
-Unlike `cargo fuzz`, these don't "ramp up" the complexity of the code, but go full tilt from the beginning, and only run for a limited amount of time (e.g. 10 seconds). Upon failure they print a hexadecimal `seed`, which can be used with the `NOIR_ARBTEST_SEED` env var to replicate the error.
+Unlike `cargo fuzz`, these don't "ramp up" the complexity of the code, but go full tilt from the beginning, and only run for a limited amount of time (e.g. 10 seconds). Upon failure they print a hexadecimal `seed`, which can be used with the `NOIR_AST_FUZZER_SEED` env var to replicate the error.
 
 ## Minimizing Noir
 
diff --git a/tooling/ast_fuzzer/fuzz/src/targets/acir_vs_brillig.rs b/tooling/ast_fuzzer/fuzz/src/targets/acir_vs_brillig.rs
index fb9684e9835..aabfa46445a 100644
--- a/tooling/ast_fuzzer/fuzz/src/targets/acir_vs_brillig.rs
+++ b/tooling/ast_fuzzer/fuzz/src/targets/acir_vs_brillig.rs
@@ -46,7 +46,7 @@ pub fn fuzz(u: &mut Unstructured) -> eyre::Result<()> {
 mod tests {
 
     /// ```ignore
-    /// NOIR_ARBTEST_SEED=0x6819c61400001000 \
+    /// NOIR_AST_FUZZER_SEED=0x6819c61400001000 \
     /// NOIR_AST_FUZZER_SHOW_AST=1 \
     /// cargo test -p noir_ast_fuzzer_fuzz acir_vs_brillig
     /// ```
diff --git a/tooling/ast_fuzzer/fuzz/src/targets/comptime_vs_brillig.rs b/tooling/ast_fuzzer/fuzz/src/targets/comptime_vs_brillig.rs
index b79a10759a5..849ac73bd90 100644
--- a/tooling/ast_fuzzer/fuzz/src/targets/comptime_vs_brillig.rs
+++ b/tooling/ast_fuzzer/fuzz/src/targets/comptime_vs_brillig.rs
@@ -50,7 +50,7 @@ pub fn fuzz(u: &mut Unstructured) -> eyre::Result<()> {
 mod tests {
 
     /// ```ignore
-    /// NOIR_ARBTEST_SEED=0x6819c61400001000 \
+    /// NOIR_AST_FUZZER_SEED=0x6819c61400001000 \
     /// NOIR_AST_FUZZER_SHOW_AST=1 \
     /// cargo test -p noir_ast_fuzzer_fuzz comptime_vs_brillig
     /// ```
diff --git a/tooling/ast_fuzzer/fuzz/src/targets/min_vs_full.rs b/tooling/ast_fuzzer/fuzz/src/targets/min_vs_full.rs
index a55f7ef93a8..364e8a83450 100644
--- a/tooling/ast_fuzzer/fuzz/src/targets/min_vs_full.rs
+++ b/tooling/ast_fuzzer/fuzz/src/targets/min_vs_full.rs
@@ -57,7 +57,7 @@ pub fn fuzz(u: &mut Unstructured) -> eyre::Result<()> {
 #[cfg(test)]
 mod tests {
     /// ```ignore
-    /// NOIR_ARBTEST_SEED=0x6819c61400001000 \
+    /// NOIR_AST_FUZZER_SEED=0x6819c61400001000 \
     /// NOIR_AST_FUZZER_SHOW_AST=1 \
     /// cargo test -p noir_ast_fuzzer_fuzz min_vs_full
     /// ```
diff --git a/tooling/ast_fuzzer/fuzz/src/targets/mod.rs b/tooling/ast_fuzzer/fuzz/src/targets/mod.rs
index 0f57694748e..bb06ff6e980 100644
--- a/tooling/ast_fuzzer/fuzz/src/targets/mod.rs
+++ b/tooling/ast_fuzzer/fuzz/src/targets/mod.rs
@@ -20,12 +20,21 @@ mod tests {
     use crate::bool_from_env;
 
     fn seed_from_env() -> Option<u64> {
-        let Ok(seed) = std::env::var("NOIR_ARBTEST_SEED") else { return None };
+        let Ok(seed) = std::env::var("NOIR_AST_FUZZER_SEED") else { return None };
         let seed = u64::from_str_radix(seed.trim_start_matches("0x"), 16)
             .unwrap_or_else(|e| panic!("failed to parse seed '{seed}': {e}"));
         Some(seed)
     }
 
+    /// How long to let non-deterministic tests run for.
+    fn budget() -> Duration {
+        std::env::var("NOIR_AST_FUZZER_BUDGET_SECS").ok().map_or(BUDGET, |b| {
+            Duration::from_secs(
+                b.parse().unwrap_or_else(|e| panic!("failed to parse budget; got {b}: {e}")),
+            )
+        })
+    }
+
     /// Check if we are running on CI.
     fn is_running_in_ci() -> bool {
         std::env::var("CI").is_ok()
@@ -36,20 +45,12 @@ mod tests {
         bool_from_env("NOIR_AST_FUZZER_FORCE_NON_DETERMINISTIC")
     }
 
-    /// How long to let non-deterministic tests run for.
-    fn budget() -> Duration {
-        std::env::var("NOIR_AST_FUZZER_BUDGET_SECS").ok().map_or(BUDGET, |b| {
-            let secs = b.parse().unwrap_or_else(|e| panic!("failed to parse budget; got {b}: {e}"));
-            Duration::from_secs(secs)
-        })
-    }
-
     /// `cargo fuzz` takes a long time to ramp up the complexity.
     /// This test catches crash bugs much faster.
     ///
     /// Run it with for example:
     /// ```ignore
-    /// NOIR_ARBTEST_SEED=0x6819c61400001000 \
+    /// NOIR_AST_FUZZER_SEED=0x6819c61400001000 \
     /// NOIR_AST_FUZZER_SHOW_AST=1 \
     /// cargo test -p noir_ast_fuzzer_fuzz acir_vs_brillig
     /// ```
diff --git a/tooling/ast_fuzzer/fuzz/src/targets/orig_vs_morph.rs b/tooling/ast_fuzzer/fuzz/src/targets/orig_vs_morph.rs
index 48664365af6..66f2cc23fb4 100644
--- a/tooling/ast_fuzzer/fuzz/src/targets/orig_vs_morph.rs
+++ b/tooling/ast_fuzzer/fuzz/src/targets/orig_vs_morph.rs
@@ -806,7 +806,7 @@ mod helpers {
 #[cfg(test)]
 mod tests {
     /// ```ignore
-    /// NOIR_ARBTEST_SEED=0xb2fb5f0b00100000 \
+    /// NOIR_AST_FUZZER_SEED=0xb2fb5f0b00100000 \
     /// NOIR_AST_FUZZER_SHOW_AST=1 \
     /// cargo test -p noir_ast_fuzzer_fuzz orig_vs_morph
     /// ```
diff --git a/tooling/ast_fuzzer/fuzz/src/targets/pass_vs_prev.rs b/tooling/ast_fuzzer/fuzz/src/targets/pass_vs_prev.rs
index 3f7b2f25022..4e73fe50821 100644
--- a/tooling/ast_fuzzer/fuzz/src/targets/pass_vs_prev.rs
+++ b/tooling/ast_fuzzer/fuzz/src/targets/pass_vs_prev.rs
@@ -65,7 +65,7 @@ fn clone_ssa(ssa: &Ssa) -> Ssa {
 #[cfg(test)]
 mod tests {
     /// ```ignore
-    /// NOIR_ARBTEST_SEED=0x6819c61400001000 \
+    /// NOIR_AST_FUZZER_SEED=0x6819c61400001000 \
     /// NOIR_AST_FUZZER_SHOW_AST=1 \
     /// cargo test -p noir_ast_fuzzer_fuzz pass_vs_prev
     /// ```
diff --git a/tooling/ast_fuzzer/src/compare/compiled.rs b/tooling/ast_fuzzer/src/compare/compiled.rs
index 79a99e68720..c5043fbf354 100644
--- a/tooling/ast_fuzzer/src/compare/compiled.rs
+++ b/tooling/ast_fuzzer/src/compare/compiled.rs
@@ -184,6 +184,13 @@ impl<P> CompareCompiled<P> {
         let blackbox_solver = Bn254BlackBoxSolver(false);
         let initial_witness = self.abi.encode(&self.input_map, None).wrap_err("abi::encode")?;
 
+        log::debug!(
+            "ABI input:\n{}",
+            noirc_abi::input_parser::Format::Toml
+                .serialize(&self.input_map, &self.abi)
+                .unwrap_or_else(|e| format!("failed to serialize inputs: {e}"))
+        );
+
         let do_exec = |program| {
             let mut print = Vec::new();
 
diff --git a/tooling/ast_fuzzer/tests/parser.rs b/tooling/ast_fuzzer/tests/parser.rs
index 76b4d15891d..7be3cb9b2f7 100644
--- a/tooling/ast_fuzzer/tests/parser.rs
+++ b/tooling/ast_fuzzer/tests/parser.rs
@@ -19,7 +19,7 @@ use noirc_evaluator::{
 };
 
 fn seed_from_env() -> Option<u64> {
-    let Ok(seed) = std::env::var("NOIR_ARBTEST_SEED") else { return None };
+    let Ok(seed) = std::env::var("NOIR_AST_FUZZER_SEED") else { return None };
     let seed = u64::from_str_radix(seed.trim_start_matches("0x"), 16)
         .unwrap_or_else(|e| panic!("failed to parse seed '{seed}': {e}"));
     Some(seed)
diff --git a/tooling/ast_fuzzer/tests/smoke.rs b/tooling/ast_fuzzer/tests/smoke.rs
index 9ff846c5d54..48917c93679 100644
--- a/tooling/ast_fuzzer/tests/smoke.rs
+++ b/tooling/ast_fuzzer/tests/smoke.rs
@@ -17,7 +17,7 @@ use noirc_abi::input_parser::Format;
 use noirc_evaluator::{brillig::BrilligOptions, ssa};
 
 fn seed_from_env() -> Option<u64> {
-    let Ok(seed) = std::env::var("NOIR_ARBTEST_SEED") else { return None };
+    let Ok(seed) = std::env::var("NOIR_AST_FUZZER_SEED") else { return None };
     let seed = u64::from_str_radix(seed.trim_start_matches("0x"), 16)
         .unwrap_or_else(|e| panic!("failed to parse seed '{seed}': {e}"));
     Some(seed)