diff --git a/Cargo.lock b/Cargo.lock
index 31fe89cdc03..f94cea81438 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1376,7 +1376,6 @@ name = "rust-analyzer"
 version = "0.1.0"
 dependencies = [
  "anyhow",
- "cargo_metadata",
  "crossbeam-channel",
  "env_logger",
  "globset",
diff --git a/crates/ra_flycheck/src/lib.rs b/crates/ra_flycheck/src/lib.rs
index 178485c9ee5..541179920ba 100644
--- a/crates/ra_flycheck/src/lib.rs
+++ b/crates/ra_flycheck/src/lib.rs
@@ -12,6 +12,11 @@ use std::{
 use cargo_metadata::Message;
 use crossbeam_channel::{never, select, unbounded, Receiver, RecvError, Sender};
 
+pub use cargo_metadata::diagnostic::{
+    Applicability, Diagnostic, DiagnosticLevel, DiagnosticSpan,
+    DiagnosticSpanMacroExpansion,
+};
+
 #[derive(Clone, Debug, PartialEq, Eq)]
 pub enum FlycheckConfig {
     CargoCommand { command: String, all_targets: bool, all_features: bool, extra_args: Vec<String> },
@@ -52,7 +57,7 @@ pub enum CheckTask {
     ClearDiagnostics,
 
     /// Request adding a diagnostic with fixes included to a file
-    AddDiagnostic { workspace_root: PathBuf, diagnostic: cargo_metadata::diagnostic::Diagnostic },
+    AddDiagnostic { workspace_root: PathBuf, diagnostic: Diagnostic },
 
     /// Request check progress notification to client
     Status(Status),
@@ -239,12 +244,6 @@ impl FlycheckThread {
     }
 }
 
-// #[derive(Debug)]
-// pub struct DiagnosticWithFixes {
-//     diagnostic: Diagnostic,
-//     fixes: Vec<CodeAction>,
-// }
-
 enum CheckEvent {
     Begin,
     Msg(cargo_metadata::Message),
diff --git a/crates/rust-analyzer/Cargo.toml b/crates/rust-analyzer/Cargo.toml
index 21e70559719..9b2d29b1d57 100644
--- a/crates/rust-analyzer/Cargo.toml
+++ b/crates/rust-analyzer/Cargo.toml
@@ -29,7 +29,6 @@ rustc-hash = "1.1.0"
 serde = { version = "1.0.106", features = ["derive"] }
 serde_json = "1.0.48"
 threadpool = "1.7.1"
-cargo_metadata = "0.10.0"
 
 stdx = { path = "../stdx" }
 
diff --git a/crates/rust-analyzer/src/diagnostics/to_proto.rs b/crates/rust-analyzer/src/diagnostics/to_proto.rs
index 0c810859128..5c8d86eb5e9 100644
--- a/crates/rust-analyzer/src/diagnostics/to_proto.rs
+++ b/crates/rust-analyzer/src/diagnostics/to_proto.rs
@@ -1,13 +1,5 @@
 //! This module provides the functionality needed to convert diagnostics from
 //! `cargo check` json format to the LSP diagnostic format.
-use cargo_metadata::diagnostic::{
-    Applicability, Diagnostic as RustDiagnostic, DiagnosticLevel, DiagnosticSpan,
-    DiagnosticSpanMacroExpansion,
-};
-use lsp_types::{
-    CodeAction, Diagnostic, DiagnosticRelatedInformation, DiagnosticSeverity, DiagnosticTag,
-    Location, NumberOrString, Position, Range, TextEdit, Url, WorkspaceEdit,
-};
 use std::{
     collections::HashMap,
     fmt::Write,
@@ -15,6 +7,12 @@ use std::{
     str::FromStr,
 };
 
+use lsp_types::{
+    CodeAction, Diagnostic, DiagnosticRelatedInformation, DiagnosticSeverity, DiagnosticTag,
+    Location, NumberOrString, Position, Range, TextEdit, Url, WorkspaceEdit,
+};
+use ra_flycheck::{Applicability, DiagnosticLevel, DiagnosticSpan, DiagnosticSpanMacroExpansion};
+
 /// Converts a Rust level string to a LSP severity
 fn map_level_to_severity(val: DiagnosticLevel) -> Option<DiagnosticSeverity> {
     match val {
@@ -91,7 +89,7 @@ fn map_secondary_span_to_related(
 }
 
 /// Determines if diagnostic is related to unused code
-fn is_unused_or_unnecessary(rd: &RustDiagnostic) -> bool {
+fn is_unused_or_unnecessary(rd: &ra_flycheck::Diagnostic) -> bool {
     if let Some(code) = &rd.code {
         match code.code.as_str() {
             "dead_code" | "unknown_lints" | "unreachable_code" | "unused_attributes"
@@ -122,7 +120,7 @@ enum MappedRustChildDiagnostic {
 }
 
 fn map_rust_child_diagnostic(
-    rd: &RustDiagnostic,
+    rd: &ra_flycheck::Diagnostic,
     workspace_root: &PathBuf,
 ) -> MappedRustChildDiagnostic {
     let spans: Vec<&DiagnosticSpan> = rd.spans.iter().filter(|s| s.is_primary).collect();
@@ -179,7 +177,7 @@ pub(crate) struct MappedRustDiagnostic {
 ///
 /// If the diagnostic has no primary span this will return `None`
 pub(crate) fn map_rust_diagnostic_to_lsp(
-    rd: &RustDiagnostic,
+    rd: &ra_flycheck::Diagnostic,
     workspace_root: &PathBuf,
 ) -> Vec<MappedRustDiagnostic> {
     let primary_spans: Vec<&DiagnosticSpan> = rd.spans.iter().filter(|s| s.is_primary).collect();