diff --git a/Cargo.lock b/Cargo.lock
index cf0c0d084c..1e17cc170f 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -121,12 +121,9 @@ checksum = "cf4b9d6a944f767f8e5e0db018570623c85f3d925ac718db4e06d0187adb21c1"
 
 [[package]]
 name = "bitmaps"
-version = "2.1.0"
+version = "3.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "031043d04099746d8db04daf1fa424b2bc8bd69d92b25962dcde24da39ab64a2"
-dependencies = [
- "typenum",
-]
+checksum = "a1d084b0137aaa901caf9f1e8b21daa6aa24d41cd806e111335541eff9683bd6"
 
 [[package]]
 name = "bitvec"
@@ -531,19 +528,27 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6fe2267d4ed49bc07b63801559be28c718ea06c4738b7a03c94df7386d2cde46"
 
 [[package]]
-name = "im"
-version = "15.1.0"
+name = "imbl"
+version = "3.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d0acd33ff0285af998aaf9b57342af478078f53492322fafc47450e09397e0e9"
+checksum = "bc3be8d8cd36f33a46b1849f31f837c44d9fa87223baee3b4bd96b8f11df81eb"
 dependencies = [
  "bitmaps",
+ "imbl-sized-chunks",
  "rand_core",
  "rand_xoshiro",
- "sized-chunks",
- "typenum",
  "version_check",
 ]
 
+[[package]]
+name = "imbl-sized-chunks"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "144006fb58ed787dcae3f54575ff4349755b00ccc99f4b4873860b654be1ed63"
+dependencies = [
+ "bitmaps",
+]
+
 [[package]]
 name = "io-uring"
 version = "0.6.4"
@@ -696,7 +701,7 @@ dependencies = [
  "fxhash",
  "hex",
  "hex-literal",
- "im",
+ "imbl",
  "io-uring",
  "lazy_static",
  "libc",
@@ -1146,16 +1151,6 @@ dependencies = [
  "lazy_static",
 ]
 
-[[package]]
-name = "sized-chunks"
-version = "0.6.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "16d69225bde7a69b235da73377861095455d298f2b970996eec25ddbb42b3d1e"
-dependencies = [
- "bitmaps",
- "typenum",
-]
-
 [[package]]
 name = "slab"
 version = "0.4.9"
diff --git a/benchtop/Cargo.lock b/benchtop/Cargo.lock
index d0ab0804cc..4abb13fde2 100644
--- a/benchtop/Cargo.lock
+++ b/benchtop/Cargo.lock
@@ -592,12 +592,9 @@ checksum = "cf4b9d6a944f767f8e5e0db018570623c85f3d925ac718db4e06d0187adb21c1"
 
 [[package]]
 name = "bitmaps"
-version = "2.1.0"
+version = "3.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "031043d04099746d8db04daf1fa424b2bc8bd69d92b25962dcde24da39ab64a2"
-dependencies = [
- "typenum",
-]
+checksum = "a1d084b0137aaa901caf9f1e8b21daa6aa24d41cd806e111335541eff9683bd6"
 
 [[package]]
 name = "bitvec"
@@ -1713,19 +1710,27 @@ dependencies = [
 ]
 
 [[package]]
-name = "im"
-version = "15.1.0"
+name = "imbl"
+version = "3.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d0acd33ff0285af998aaf9b57342af478078f53492322fafc47450e09397e0e9"
+checksum = "bc3be8d8cd36f33a46b1849f31f837c44d9fa87223baee3b4bd96b8f11df81eb"
 dependencies = [
  "bitmaps",
+ "imbl-sized-chunks",
  "rand_core 0.6.4",
  "rand_xoshiro",
- "sized-chunks",
- "typenum",
  "version_check",
 ]
 
+[[package]]
+name = "imbl-sized-chunks"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "144006fb58ed787dcae3f54575ff4349755b00ccc99f4b4873860b654be1ed63"
+dependencies = [
+ "bitmaps",
+]
+
 [[package]]
 name = "impl-codec"
 version = "0.6.0"
@@ -2219,7 +2224,7 @@ dependencies = [
  "dashmap",
  "fs2",
  "fxhash",
- "im",
+ "imbl",
  "io-uring",
  "libc",
  "loom",
@@ -3326,16 +3331,6 @@ dependencies = [
  "rand_core 0.6.4",
 ]
 
-[[package]]
-name = "sized-chunks"
-version = "0.6.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "16d69225bde7a69b235da73377861095455d298f2b970996eec25ddbb42b3d1e"
-dependencies = [
- "bitmaps",
- "typenum",
-]
-
 [[package]]
 name = "slab"
 version = "0.4.9"
diff --git a/nomt/Cargo.toml b/nomt/Cargo.toml
index ea1b8457ad..4dd7b2d8b2 100644
--- a/nomt/Cargo.toml
+++ b/nomt/Cargo.toml
@@ -24,7 +24,7 @@ crossbeam-channel = "0.5.13"
 slab = "0.4.9"
 rand = "0.8.5"
 ahash = "0.8.11"
-im = "15.1.0"
+imbl = "3.0.0"
 lru = "0.12.3"
 libc = "0.2.155"
 criterion = { version = "0.3", optional = true }
diff --git a/nomt/src/beatree/index.rs b/nomt/src/beatree/index.rs
index da09c12938..cd5257094f 100644
--- a/nomt/src/beatree/index.rs
+++ b/nomt/src/beatree/index.rs
@@ -5,7 +5,7 @@ use std::iter::DoubleEndedIterator;
 use std::ops::{Bound, RangeBounds, RangeToInclusive};
 use std::sync::Arc;
 
-use im::OrdMap;
+use imbl::OrdMap;
 
 use super::Key;
 use crate::beatree::branch::BranchNode;