diff --git a/README.md b/README.md
index 77439ec..04cb21b 100644
--- a/README.md
+++ b/README.md
@@ -52,6 +52,11 @@ development environment:
 
 ## Running the binding generator
 
+Running the binding generator requires GIR files to process. The easiest way to
+get the full set of required GIR files is to set up a Flatpak development
+environment as described in the previous section. Otherwise, a custom set of
+bindings can be built by running the `zig-gobject` binary directly.
+
 To generate all available bindings using the files under `lib/gir-files`, run
 `zig build codegen`. This will generate bindings to the `bindings` directory,
 which can be used as a dependency (using the Zig package manager) in other
diff --git a/build.zig b/build.zig
index 1ff5975..a3221ab 100644
--- a/build.zig
+++ b/build.zig
@@ -187,8 +187,8 @@ fn addCodegenStep(b: *std.Build, codegen_exe: *std.Build.Step.Compile) !*std.Bui
 
     const codegen_cmd = b.addRunArtifact(codegen_exe);
     codegen_cmd.addArgs(&.{ "--gir-dir", try b.build_root.join(b.allocator, &.{"gir-overrides"}) });
-    codegen_cmd.addArg("--gir-dir");
-    codegen_cmd.addDirectoryArg(b.dependency("gir", .{}).path("."));
+    const gir_files_path = b.option([]const u8, "gir-files-path", "Path to GIR files") orelse "/usr/share/gir-1.0";
+    codegen_cmd.addArgs(&.{ "--gir-dir", gir_files_path });
     codegen_cmd.addArgs(&.{ "--bindings-dir", try b.build_root.join(b.allocator, &.{"binding-overrides"}) });
     codegen_cmd.addArgs(&.{ "--extensions-dir", try b.build_root.join(b.allocator, &.{"extensions"}) });
     codegen_cmd.addArgs(&.{ "--output-dir", try b.build_root.join(b.allocator, &.{"bindings"}) });
diff --git a/build.zig.zon b/build.zig.zon
index 5e1198f..49931e5 100644
--- a/build.zig.zon
+++ b/build.zig.zon
@@ -9,10 +9,6 @@
         "build.zig.zon",
     },
     .dependencies = .{
-        .gir = .{
-            .url = "git+https://github.com/ianprime0509/gir-files#d0d06238bc0f1759b450cc7113f8fc3637c6533d",
-            .hash = "1220d03206a277aa5adac91667c7ff7236017fde65c2034bdeec3203cfca09a7152e",
-        },
         .xml = .{
             .url = "git+https://github.com/ianprime0509/zig-xml#5d995ef95bb5796f38bf16c0d4750cba06d86549",
             .hash = "1220d70515390ed942a0864fe3aad2f3b485b3fcb9df07d61dbefea9873373647e33",
diff --git a/src/gir.zig b/src/gir.zig
index 01ae683..230050f 100644
--- a/src/gir.zig
+++ b/src/gir.zig
@@ -3,16 +3,26 @@ const xml = @import("xml");
 const mem = std.mem;
 const Allocator = mem.Allocator;
 
-pub const FindError = error{ InvalidGir, RepositoryNotFound } || Allocator.Error || std.fs.File.OpenError || std.fs.File.ReadError || error{
-    FileSystem,
-    InputOutput,
-    NotSupported,
-    Unseekable,
+pub const Diagnostics = struct {
+    errors: std.ArrayListUnmanaged([]u8) = .{},
+    allocator: Allocator,
+
+    pub fn deinit(diag: *Diagnostics) void {
+        for (diag.errors.items) |err| diag.allocator.free(err);
+        diag.errors.deinit(diag.allocator);
+        diag.* = undefined;
+    }
+
+    fn add(diag: *Diagnostics, comptime fmt: []const u8, args: anytype) Allocator.Error!void {
+        const formatted = try std.fmt.allocPrint(diag.allocator, fmt, args);
+        errdefer diag.allocator.free(formatted);
+        try diag.errors.append(diag.allocator, formatted);
+    }
 };
 
 /// Finds and parses all repositories for the given root libraries, transitively
 /// including dependencies.
-pub fn findRepositories(allocator: Allocator, gir_path: []const std.fs.Dir, roots: []const Include) FindError![]Repository {
+pub fn findRepositories(allocator: Allocator, gir_path: []const std.fs.Dir, roots: []const Include, diag: *Diagnostics) Allocator.Error![]Repository {
     var repos = std.ArrayHashMap(Include, Repository, Include.ArrayContext, true).init(allocator);
     defer repos.deinit();
     errdefer for (repos.values()) |*repo| repo.deinit();
@@ -22,7 +32,10 @@ pub fn findRepositories(allocator: Allocator, gir_path: []const std.fs.Dir, root
     try needed_repos.appendSlice(roots);
     while (needed_repos.popOrNull()) |needed_repo| {
         if (!repos.contains(needed_repo)) {
-            const repo = try findRepository(allocator, gir_path, needed_repo);
+            const repo = findRepository(allocator, gir_path, needed_repo, diag) catch |err| switch (err) {
+                error.OutOfMemory => return error.OutOfMemory,
+                error.FindFailed => continue,
+            };
             try repos.put(needed_repo, repo);
             try needed_repos.appendSlice(repo.includes);
         }
@@ -31,19 +44,35 @@ pub fn findRepositories(allocator: Allocator, gir_path: []const std.fs.Dir, root
     return try allocator.dupe(Repository, repos.values());
 }
 
-fn findRepository(allocator: Allocator, gir_path: []const std.fs.Dir, include: Include) !Repository {
+fn findRepository(allocator: Allocator, gir_path: []const std.fs.Dir, include: Include, diag: *Diagnostics) !Repository {
     const repo_path = try std.fmt.allocPrintZ(allocator, "{s}-{s}.gir", .{ include.name, include.version });
     defer allocator.free(repo_path);
+
     for (gir_path) |dir| {
         const file = dir.openFile(repo_path, .{}) catch |err| switch (err) {
             error.FileNotFound => continue,
-            else => |other| return other,
+            else => {
+                try diag.add("failed to open GIR file: {s}: {}", .{ repo_path, err });
+                return error.FindFailed;
+            },
         };
         defer file.close();
         var reader = std.io.bufferedReader(file.reader());
-        return try Repository.parse(allocator, reader.reader());
+        return Repository.parse(allocator, reader.reader()) catch |err| switch (err) {
+            error.OutOfMemory => return error.OutOfMemory,
+            error.InvalidGir => {
+                try diag.add("failed to parse GIR file: {s}", .{repo_path});
+                return error.FindFailed;
+            },
+            else => {
+                try diag.add("failed to read GIR file: {s}: {}", .{ repo_path, err });
+                return error.FindFailed;
+            },
+        };
     }
-    return error.RepositoryNotFound;
+
+    try diag.add("failed to find GIR file: {s}", .{repo_path});
+    return error.FindFailed;
 }
 
 const ns = struct {
diff --git a/src/main.zig b/src/main.zig
index f379b19..4923f19 100644
--- a/src/main.zig
+++ b/src/main.zig
@@ -122,7 +122,18 @@ pub fn main() Allocator.Error!void {
     var src_out_dir = output_dir.?.makeOpenPath("src", .{}) catch |err| fatal("failed to create output src directory: {}", .{err});
     defer src_out_dir.close();
 
-    const repositories = gir.findRepositories(allocator, gir_path.items, roots.items) catch |err| fatal("failed to discover GIR repositories: {}", .{err});
+    const repositories = repositories: {
+        var diag: gir.Diagnostics = .{ .allocator = allocator };
+        defer diag.deinit();
+        const repositories = try gir.findRepositories(allocator, gir_path.items, roots.items, &diag);
+        if (diag.errors.items.len > 0) {
+            for (diag.errors.items) |err| {
+                log.err("{s}", .{err});
+            }
+            fatal("failed to find and parse GIR repositories", .{});
+        }
+        break :repositories repositories;
+    };
     defer allocator.free(repositories);
     defer for (repositories) |*repository| repository.deinit();
     translate.createBindings(allocator, repositories, bindings_path.items, extensions_path.items, src_out_dir) catch |err| fatal("failed to create bindings: {}", .{err});