diff --git a/Cargo.lock b/Cargo.lock
index 07188e615..d98c10bdd 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -623,15 +623,6 @@ version = "2.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "879d54834c8c76457ef4293a689b2a8c59b076067ad77b15efafbb05f92a592b"
 
-[[package]]
-name = "itertools"
-version = "0.12.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "25db6b064527c5d482d0423354fcd07a89a2dfe07b67892e62411946db7f07b0"
-dependencies = [
- "either",
-]
-
 [[package]]
 name = "itoa"
 version = "1.0.2"
@@ -1005,7 +996,6 @@ dependencies = [
  "duct",
  "env_logger",
  "indexmap 2.1.0",
- "itertools",
  "log",
  "rayon",
  "regex",
diff --git a/Cargo.toml b/Cargo.toml
index 30e4cfaa7..6f73daa0f 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -10,7 +10,6 @@ base64 = "0.13.0"
 dialoguer = "0.10.1"
 env_logger = { version = "0.9.0", default-features = false }
 indexmap = "2"
-itertools = "0.12"
 log = "0.4"
 rayon = "1.5"
 regex = "1.5.5"
diff --git a/src/validate.rs b/src/validate.rs
index 81584fca5..5357e4026 100644
--- a/src/validate.rs
+++ b/src/validate.rs
@@ -3,7 +3,6 @@ use crate::github::GitHubApi;
 use crate::schema::{Bot, Email, Permissions, Team, TeamKind, TeamPeople, ZulipGroupMember};
 use crate::zulip::ZulipApi;
 use anyhow::{bail, Error};
-use itertools::Itertools as _;
 use log::{error, warn};
 use regex::Regex;
 use std::collections::hash_map::{Entry, HashMap};
@@ -635,9 +634,10 @@ fn validate_discord_team_members_have_discord_ids(data: &Data, errors: &mut Vec<
         if team.discord_roles().is_some() && team.name() != "all" {
             let team_members = team.members(data)?;
             if team_members.len() != team.discord_ids(data)?.len() {
-                let mut missing_discord_id = team_members
+                let missing_discord_id = team_members
                     .into_iter()
-                    .filter(|name| data.person(name).map(|p| p.discord_id()) == Some(None));
+                    .filter(|name| data.person(name).map(|p| p.discord_id()) == Some(None))
+                    .collect::<Vec<_>>();
 
                 bail!(
                     "the following members of the \"{}\" team do not have discord_ids: {}",