diff --git a/Cargo.lock b/Cargo.lock
index 1a81bb0729..abd29daaa0 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -3797,7 +3797,6 @@ dependencies = [
  "roc_types",
  "roc_unify",
  "rodio",
- "ropey",
  "serde",
  "snafu",
  "tempfile",
@@ -3807,7 +3806,6 @@ dependencies = [
  "wgpu",
  "wgpu_glyph",
  "winit",
- "zerocopy",
 ]
 
 [[package]]
@@ -4160,15 +4158,6 @@ dependencies = [
  "minimp3",
 ]
 
-[[package]]
-name = "ropey"
-version = "1.3.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9150aff6deb25b20ed110889f070a678bcd1033e46e5e9d6fb1abeab17947f28"
-dependencies = [
- "smallvec",
-]
-
 [[package]]
 name = "rustc-demangle"
 version = "0.1.21"
@@ -4614,18 +4603,6 @@ dependencies = [
  "unicode-xid 0.2.2",
 ]
 
-[[package]]
-name = "synstructure"
-version = "0.12.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "474aaa926faa1603c40b7885a9eaea29b444d1cb2850cb7c0e37bb1a4182f4fa"
-dependencies = [
- "proc-macro2 1.0.29",
- "quote 1.0.9",
- "syn 1.0.76",
- "unicode-xid 0.2.2",
-]
-
 [[package]]
 name = "target-lexicon"
 version = "0.12.2"
@@ -4700,31 +4677,17 @@ name = "test_mono"
 version = "0.1.0"
 dependencies = [
  "bumpalo",
- "either",
- "im 14.3.0",
- "im-rc 14.3.0",
  "indoc 0.3.6",
  "libc",
- "libloading 0.6.7",
  "pretty_assertions 0.5.1",
  "quickcheck 0.8.5",
  "quickcheck_macros 0.8.0",
- "roc_build",
  "roc_builtins",
  "roc_can",
  "roc_collections",
- "roc_constrain",
  "roc_load",
  "roc_module",
  "roc_mono",
- "roc_parse",
- "roc_problem",
- "roc_region",
- "roc_reporting",
- "roc_solve",
- "roc_types",
- "roc_unify",
- "target-lexicon",
  "test_mono_macros",
 ]
 
@@ -4732,7 +4695,6 @@ dependencies = [
 name = "test_mono_macros"
 version = "0.1.0"
 dependencies = [
- "darling 0.10.2",
  "proc-macro2 1.0.29",
  "quote 1.0.9",
  "syn 1.0.76",
@@ -5762,24 +5724,3 @@ checksum = "56c1936c4cc7a1c9ab21a1ebb602eb942ba868cbd44a99cb7cdc5892335e1c85"
 dependencies = [
  "linked-hash-map",
 ]
-
-[[package]]
-name = "zerocopy"
-version = "0.3.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6580539ad917b7c026220c4b3f2c08d52ce54d6ce0dc491e66002e35388fab46"
-dependencies = [
- "byteorder",
- "zerocopy-derive",
-]
-
-[[package]]
-name = "zerocopy-derive"
-version = "0.2.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d498dbd1fd7beb83c86709ae1c33ca50942889473473d287d56ce4770a18edfb"
-dependencies = [
- "proc-macro2 1.0.29",
- "syn 1.0.76",
- "synstructure",
-]
diff --git a/compiler/test_mono/Cargo.toml b/compiler/test_mono/Cargo.toml
index 1d8f772023..879932a4df 100644
--- a/compiler/test_mono/Cargo.toml
+++ b/compiler/test_mono/Cargo.toml
@@ -7,29 +7,15 @@ edition = "2018"
 
 [dependencies]
 roc_collections = { path = "../collections" }
-roc_region = { path = "../region" }
 roc_module = { path = "../module" }
-roc_problem = { path = "../problem" }
-roc_types = { path = "../types" }
 roc_builtins = { path = "../builtins" }
-roc_constrain = { path = "../constrain" }
-roc_unify = { path = "../unify" }
-roc_solve = { path = "../solve" }
-roc_reporting = { path = "../reporting" }
 roc_load = { path = "../load" }
 roc_can = { path = "../can" }
-roc_parse = { path = "../parse" }
-roc_build = { path = "../build" }
 roc_mono = { path = "../mono" }
 test_mono_macros = { path = "../test_mono_macros" }
-im    = "14" # im and im-rc should always have the same version!
-im-rc = "14" # im and im-rc should always have the same version!
 bumpalo = { version = "3.6.1", features = ["collections"] }
-either = "1.6.1"
 indoc = "0.3.3"
 libc = "0.2"
-target-lexicon = "0.12.2"
-libloading = "0.6"
 
 [dev-dependencies]
 pretty_assertions = "0.5.1"
diff --git a/compiler/test_mono_macros/Cargo.toml b/compiler/test_mono_macros/Cargo.toml
index 24ddaa408b..dcf87eb915 100644
--- a/compiler/test_mono_macros/Cargo.toml
+++ b/compiler/test_mono_macros/Cargo.toml
@@ -11,5 +11,4 @@ proc-macro = true
 [dependencies]
 syn = { version = "1.0.39", features = ["full", "extra-traits"] }
 quote = "1.0.7"
-darling = "0.10.2"
 proc-macro2 = "1.0.24"
diff --git a/editor/Cargo.toml b/editor/Cargo.toml
index 6d8d1673ca..c915a475b5 100644
--- a/editor/Cargo.toml
+++ b/editor/Cargo.toml
@@ -32,7 +32,6 @@ winit = "0.24"
 wgpu = "0.10"
 glyph_brush = "0.7"
 log = "0.4"
-zerocopy = "0.3"
 env_logger = "0.8"
 futures = "0.3"
 wgpu_glyph = "0.14"
@@ -41,7 +40,6 @@ snafu = { version = "0.6", features = ["backtraces"] }
 colored = "2"
 pest = "2.1"
 pest_derive = "2.1"
-ropey = "1.2.0"
 copypasta = "0.7.1"
 palette = "0.5"
 # confy is currently unused but should not be removed