diff --git a/src/DocumentStore.zig b/src/DocumentStore.zig
index eafd08a..be84f81 100644
--- a/src/DocumentStore.zig
+++ b/src/DocumentStore.zig
@@ -100,7 +100,7 @@ pub fn deinit(self: *DocumentStore) void {
 }
 
 /// returns a handle to the given document
-pub fn getHandle(self: *DocumentStore, uri: Uri) ?*Handle {
+pub fn getHandle(self: *const DocumentStore, uri: Uri) ?*Handle {
     const handle = self.handles.getPtr(uri) orelse {
         log.warn("Trying to open non existent document {s}", .{uri});
         return null;
diff --git a/src/Server.zig b/src/Server.zig
index a4f3a6b..95a9f9c 100644
--- a/src/Server.zig
+++ b/src/Server.zig
@@ -379,7 +379,7 @@ fn typeToCompletion(
     server: *Server,
     list: *std.ArrayListUnmanaged(types.CompletionItem),
     field_access: analysis.FieldAccessReturn,
-    orig_handle: *DocumentStore.Handle,
+    orig_handle: *const DocumentStore.Handle,
 ) error{OutOfMemory}!void {
     var allocator = server.arena.allocator();
 
@@ -441,7 +441,7 @@ fn nodeToCompletion(
     list: *std.ArrayListUnmanaged(types.CompletionItem),
     node_handle: analysis.NodeWithHandle,
     unwrapped: ?analysis.TypeWithHandle,
-    orig_handle: *DocumentStore.Handle,
+    orig_handle: *const DocumentStore.Handle,
     is_type_val: bool,
     parent_is_type_val: ?bool,
 ) error{OutOfMemory}!void {
@@ -811,7 +811,7 @@ fn hoverSymbol(server: *Server, decl_handle: analysis.DeclWithHandle) error{OutO
     };
 }
 
-fn getLabelGlobal(pos_index: usize, handle: *DocumentStore.Handle) error{OutOfMemory}!?analysis.DeclWithHandle {
+fn getLabelGlobal(pos_index: usize, handle: *const DocumentStore.Handle) error{OutOfMemory}!?analysis.DeclWithHandle {
     const tracy_zone = tracy.trace(@src());
     defer tracy_zone.end();
 
@@ -824,7 +824,7 @@ fn getLabelGlobal(pos_index: usize, handle: *DocumentStore.Handle) error{OutOfMe
 fn getSymbolGlobal(
     server: *Server,
     pos_index: usize,
-    handle: *DocumentStore.Handle,
+    handle: *const DocumentStore.Handle,
 ) error{OutOfMemory}!?analysis.DeclWithHandle {
     const tracy_zone = tracy.trace(@src());
     defer tracy_zone.end();
@@ -838,7 +838,7 @@ fn getSymbolGlobal(
 fn gotoDefinitionLabel(
     server: *Server,
     pos_index: usize,
-    handle: *DocumentStore.Handle,
+    handle: *const DocumentStore.Handle,
 ) error{OutOfMemory}!?types.Location {
     const tracy_zone = tracy.trace(@src());
     defer tracy_zone.end();
@@ -850,7 +850,7 @@ fn gotoDefinitionLabel(
 fn gotoDefinitionGlobal(
     server: *Server,
     pos_index: usize,
-    handle: *DocumentStore.Handle,
+    handle: *const DocumentStore.Handle,
     resolve_alias: bool,
 ) error{OutOfMemory}!?types.Location {
     const tracy_zone = tracy.trace(@src());
@@ -860,7 +860,7 @@ fn gotoDefinitionGlobal(
     return try server.gotoDefinitionSymbol(decl, resolve_alias);
 }
 
-fn hoverDefinitionLabel(server: *Server, pos_index: usize, handle: *DocumentStore.Handle) error{OutOfMemory}!?types.Hover {
+fn hoverDefinitionLabel(server: *Server, pos_index: usize, handle: *const DocumentStore.Handle) error{OutOfMemory}!?types.Hover {
     const tracy_zone = tracy.trace(@src());
     defer tracy_zone.end();
 
@@ -868,7 +868,7 @@ fn hoverDefinitionLabel(server: *Server, pos_index: usize, handle: *DocumentStor
     return try server.hoverSymbol(decl);
 }
 
-fn hoverDefinitionBuiltin(server: *Server, pos_index: usize, handle: *DocumentStore.Handle) error{OutOfMemory}!?types.Hover {
+fn hoverDefinitionBuiltin(server: *Server, pos_index: usize, handle: *const DocumentStore.Handle) error{OutOfMemory}!?types.Hover {
     const tracy_zone = tracy.trace(@src());
     defer tracy_zone.end();
 
@@ -892,7 +892,7 @@ fn hoverDefinitionBuiltin(server: *Server, pos_index: usize, handle: *DocumentSt
     return null;
 }
 
-fn hoverDefinitionGlobal(server: *Server, pos_index: usize, handle: *DocumentStore.Handle) error{OutOfMemory}!?types.Hover {
+fn hoverDefinitionGlobal(server: *Server, pos_index: usize, handle: *const DocumentStore.Handle) error{OutOfMemory}!?types.Hover {
     const tracy_zone = tracy.trace(@src());
     defer tracy_zone.end();
 
@@ -902,7 +902,7 @@ fn hoverDefinitionGlobal(server: *Server, pos_index: usize, handle: *DocumentSto
 
 fn getSymbolFieldAccess(
     server: *Server,
-    handle: *DocumentStore.Handle,
+    handle: *const DocumentStore.Handle,
     source_index: usize,
     loc: offsets.Loc,
 ) !?analysis.DeclWithHandle {
@@ -934,7 +934,7 @@ fn getSymbolFieldAccess(
 
 fn gotoDefinitionFieldAccess(
     server: *Server,
-    handle: *DocumentStore.Handle,
+    handle: *const DocumentStore.Handle,
     source_index: usize,
     loc: offsets.Loc,
     resolve_alias: bool,
@@ -948,7 +948,7 @@ fn gotoDefinitionFieldAccess(
 
 fn hoverDefinitionFieldAccess(
     server: *Server,
-    handle: *DocumentStore.Handle,
+    handle: *const DocumentStore.Handle,
     source_index: usize,
     loc: offsets.Loc,
 ) error{OutOfMemory}!?types.Hover {
@@ -962,7 +962,7 @@ fn hoverDefinitionFieldAccess(
 fn gotoDefinitionString(
     server: *Server,
     pos_index: usize,
-    handle: *DocumentStore.Handle,
+    handle: *const DocumentStore.Handle,
 ) error{OutOfMemory}!?types.Location {
     const tracy_zone = tracy.trace(@src());
     defer tracy_zone.end();
@@ -982,7 +982,7 @@ fn gotoDefinitionString(
 const DeclToCompletionContext = struct {
     server: *Server,
     completions: *std.ArrayListUnmanaged(types.CompletionItem),
-    orig_handle: *DocumentStore.Handle,
+    orig_handle: *const DocumentStore.Handle,
     parent_is_type_val: ?bool = null,
 };
 
@@ -1071,7 +1071,7 @@ fn declToCompletion(context: DeclToCompletionContext, decl_handle: analysis.Decl
 fn completeLabel(
     server: *Server,
     pos_index: usize,
-    handle: *DocumentStore.Handle,
+    handle: *const DocumentStore.Handle,
 ) ![]types.CompletionItem {
     const tracy_zone = tracy.trace(@src());
     defer tracy_zone.end();
@@ -1112,7 +1112,7 @@ fn populateSnippedCompletions(
     }
 }
 
-fn completeGlobal(server: *Server, pos_index: usize, handle: *DocumentStore.Handle) ![]types.CompletionItem {
+fn completeGlobal(server: *Server, pos_index: usize, handle: *const DocumentStore.Handle) ![]types.CompletionItem {
     const tracy_zone = tracy.trace(@src());
     defer tracy_zone.end();
 
@@ -1135,7 +1135,7 @@ fn completeGlobal(server: *Server, pos_index: usize, handle: *DocumentStore.Hand
     return completions.toOwnedSlice(server.arena.allocator());
 }
 
-fn completeFieldAccess(server: *Server, handle: *DocumentStore.Handle, source_index: usize, loc: offsets.Loc) !?[]types.CompletionItem {
+fn completeFieldAccess(server: *Server, handle: *const DocumentStore.Handle, source_index: usize, loc: offsets.Loc) !?[]types.CompletionItem {
     const tracy_zone = tracy.trace(@src());
     defer tracy_zone.end();
 
@@ -1322,7 +1322,7 @@ fn formatDetailledLabel(item: *types.CompletionItem, alloc: std.mem.Allocator) !
     //     logger.info("labelDetails: {s}  ::  {s}", .{item.labelDetails.?.detail, item.labelDetails.?.description});
 }
 
-fn completeError(server: *Server, handle: *DocumentStore.Handle) ![]types.CompletionItem {
+fn completeError(server: *Server, handle: *const DocumentStore.Handle) ![]types.CompletionItem {
     const tracy_zone = tracy.trace(@src());
     defer tracy_zone.end();
 
@@ -1357,7 +1357,7 @@ fn kindToSortScore(kind: types.CompletionItem.Kind) ?[]const u8 {
     };
 }
 
-fn completeDot(server: *Server, handle: *DocumentStore.Handle) ![]types.CompletionItem {
+fn completeDot(server: *Server, handle: *const DocumentStore.Handle) ![]types.CompletionItem {
     const tracy_zone = tracy.trace(@src());
     defer tracy_zone.end();
 
@@ -1366,7 +1366,7 @@ fn completeDot(server: *Server, handle: *DocumentStore.Handle) ![]types.Completi
     return completions;
 }
 
-fn completeFileSystemStringLiteral(allocator: std.mem.Allocator, store: *const DocumentStore, handle: *DocumentStore.Handle, completing: []const u8, is_import: bool) ![]types.CompletionItem {
+fn completeFileSystemStringLiteral(allocator: std.mem.Allocator, store: *const DocumentStore, handle: *const DocumentStore.Handle, completing: []const u8, is_import: bool) ![]types.CompletionItem {
     var subpath_present = false;
     var completions = std.ArrayListUnmanaged(types.CompletionItem){};
 
@@ -1422,7 +1422,7 @@ fn completeFileSystemStringLiteral(allocator: std.mem.Allocator, store: *const D
     return completions.toOwnedSlice(allocator);
 }
 
-fn documentSymbol(server: *Server, writer: anytype, id: types.RequestId, handle: *DocumentStore.Handle) !void {
+fn documentSymbol(server: *Server, writer: anytype, id: types.RequestId, handle: *const DocumentStore.Handle) !void {
     const tracy_zone = tracy.trace(@src());
     defer tracy_zone.end();
 
diff --git a/src/analysis.zig b/src/analysis.zig
index b0c236a..168683d 100644
--- a/src/analysis.zig
+++ b/src/analysis.zig
@@ -47,7 +47,7 @@ pub fn getDocComments(allocator: std.mem.Allocator, tree: Ast, node: Ast.Node.In
 }
 
 /// Get the first doc comment of a declaration.
-pub fn getDocCommentTokenIndex(tokens: []std.zig.Token.Tag, base_token: Ast.TokenIndex) ?Ast.TokenIndex {
+pub fn getDocCommentTokenIndex(tokens: []const std.zig.Token.Tag, base_token: Ast.TokenIndex) ?Ast.TokenIndex {
     var idx = base_token;
     if (idx == 0) return null;
     idx -= 1;
@@ -181,7 +181,7 @@ pub fn getFunctionSnippet(allocator: std.mem.Allocator, tree: Ast, func: Ast.ful
     return buffer.toOwnedSlice(allocator);
 }
 
-pub fn hasSelfParam(arena: *std.heap.ArenaAllocator, document_store: *DocumentStore, handle: *DocumentStore.Handle, func: Ast.full.FnProto) !bool {
+pub fn hasSelfParam(arena: *std.heap.ArenaAllocator, document_store: *const DocumentStore, handle: *const DocumentStore.Handle, func: Ast.full.FnProto) !bool {
     // Non-decl prototypes cannot have a self parameter.
     if (func.name_token == null) return false;
     if (func.ast.params.len == 0) return false;
@@ -314,7 +314,7 @@ fn getDeclName(tree: Ast, node: Ast.Node.Index) ?[]const u8 {
     };
 }
 
-fn resolveVarDeclAliasInternal(store: *DocumentStore, arena: *std.heap.ArenaAllocator, node_handle: NodeWithHandle, root: bool) error{OutOfMemory}!?DeclWithHandle {
+fn resolveVarDeclAliasInternal(store: *const DocumentStore, arena: *std.heap.ArenaAllocator, node_handle: NodeWithHandle, root: bool) error{OutOfMemory}!?DeclWithHandle {
     _ = root;
     const handle = node_handle.handle;
     const tree = handle.tree;
@@ -367,7 +367,7 @@ fn resolveVarDeclAliasInternal(store: *DocumentStore, arena: *std.heap.ArenaAllo
 /// const decl = @import("decl-file.zig").decl;
 /// const other = decl.middle.other;
 ///```
-pub fn resolveVarDeclAlias(store: *DocumentStore, arena: *std.heap.ArenaAllocator, decl_handle: NodeWithHandle) !?DeclWithHandle {
+pub fn resolveVarDeclAlias(store: *const DocumentStore, arena: *std.heap.ArenaAllocator, decl_handle: NodeWithHandle) !?DeclWithHandle {
     const decl = decl_handle.node;
     const handle = decl_handle.handle;
     const tree = handle.tree;
@@ -431,7 +431,7 @@ fn findReturnStatement(tree: Ast, fn_decl: Ast.full.FnProto, body: Ast.Node.Inde
     return findReturnStatementInternal(tree, fn_decl, body, &already_found);
 }
 
-pub fn resolveReturnType(store: *DocumentStore, arena: *std.heap.ArenaAllocator, fn_decl: Ast.full.FnProto, handle: *DocumentStore.Handle, bound_type_params: *BoundTypeParams, fn_body: ?Ast.Node.Index) !?TypeWithHandle {
+pub fn resolveReturnType(store: *const DocumentStore, arena: *std.heap.ArenaAllocator, fn_decl: Ast.full.FnProto, handle: *const DocumentStore.Handle, bound_type_params: *BoundTypeParams, fn_body: ?Ast.Node.Index) !?TypeWithHandle {
     const tree = handle.tree;
     if (isTypeFunction(tree, fn_decl) and fn_body != null) {
         // If this is a type function and it only contains a single return statement that returns
@@ -468,7 +468,7 @@ pub fn resolveReturnType(store: *DocumentStore, arena: *std.heap.ArenaAllocator,
 }
 
 /// Resolves the child type of an optional type
-fn resolveUnwrapOptionalType(store: *DocumentStore, arena: *std.heap.ArenaAllocator, opt: TypeWithHandle, bound_type_params: *BoundTypeParams) !?TypeWithHandle {
+fn resolveUnwrapOptionalType(store: *const DocumentStore, arena: *std.heap.ArenaAllocator, opt: TypeWithHandle, bound_type_params: *BoundTypeParams) !?TypeWithHandle {
     const opt_node = switch (opt.type.data) {
         .other => |n| n,
         else => return null,
@@ -484,7 +484,7 @@ fn resolveUnwrapOptionalType(store: *DocumentStore, arena: *std.heap.ArenaAlloca
     return null;
 }
 
-fn resolveUnwrapErrorType(store: *DocumentStore, arena: *std.heap.ArenaAllocator, rhs: TypeWithHandle, bound_type_params: *BoundTypeParams) !?TypeWithHandle {
+fn resolveUnwrapErrorType(store: *const DocumentStore, arena: *std.heap.ArenaAllocator, rhs: TypeWithHandle, bound_type_params: *BoundTypeParams) !?TypeWithHandle {
     const rhs_node = switch (rhs.type.data) {
         .other => |n| n,
         .error_union => |n| return TypeWithHandle{
@@ -505,7 +505,7 @@ fn resolveUnwrapErrorType(store: *DocumentStore, arena: *std.heap.ArenaAllocator
 }
 
 /// Resolves the child type of a deref type
-fn resolveDerefType(store: *DocumentStore, arena: *std.heap.ArenaAllocator, deref: TypeWithHandle, bound_type_params: *BoundTypeParams) !?TypeWithHandle {
+fn resolveDerefType(store: *const DocumentStore, arena: *std.heap.ArenaAllocator, deref: TypeWithHandle, bound_type_params: *BoundTypeParams) !?TypeWithHandle {
     const deref_node = switch (deref.type.data) {
         .other => |n| n,
         .pointer => |n| return TypeWithHandle{
@@ -538,7 +538,7 @@ fn resolveDerefType(store: *DocumentStore, arena: *std.heap.ArenaAllocator, dere
 }
 
 /// Resolves slicing and array access
-fn resolveBracketAccessType(store: *DocumentStore, arena: *std.heap.ArenaAllocator, lhs: TypeWithHandle, rhs: enum { Single, Range }, bound_type_params: *BoundTypeParams) !?TypeWithHandle {
+fn resolveBracketAccessType(store: *const DocumentStore, arena: *std.heap.ArenaAllocator, lhs: TypeWithHandle, rhs: enum { Single, Range }, bound_type_params: *BoundTypeParams) !?TypeWithHandle {
     const lhs_node = switch (lhs.type.data) {
         .other => |n| n,
         else => return null,
@@ -575,7 +575,7 @@ fn resolveBracketAccessType(store: *DocumentStore, arena: *std.heap.ArenaAllocat
 }
 
 /// Called to remove one level of pointerness before a field access
-pub fn resolveFieldAccessLhsType(store: *DocumentStore, arena: *std.heap.ArenaAllocator, lhs: TypeWithHandle, bound_type_params: *BoundTypeParams) !TypeWithHandle {
+pub fn resolveFieldAccessLhsType(store: *const DocumentStore, arena: *std.heap.ArenaAllocator, lhs: TypeWithHandle, bound_type_params: *BoundTypeParams) !TypeWithHandle {
     return (try resolveDerefType(store, arena, lhs, bound_type_params)) orelse lhs;
 }
 
@@ -614,7 +614,7 @@ pub fn isTypeIdent(text: []const u8) bool {
 }
 
 /// Resolves the type of a node
-pub fn resolveTypeOfNodeInternal(store: *DocumentStore, arena: *std.heap.ArenaAllocator, node_handle: NodeWithHandle, bound_type_params: *BoundTypeParams) error{OutOfMemory}!?TypeWithHandle {
+pub fn resolveTypeOfNodeInternal(store: *const DocumentStore, arena: *std.heap.ArenaAllocator, node_handle: NodeWithHandle, bound_type_params: *BoundTypeParams) error{OutOfMemory}!?TypeWithHandle {
     // If we were asked to resolve this node before,
     // it is self-referential and we cannot resolve it.
     for (resolve_trail.items) |i| {
@@ -972,7 +972,7 @@ pub const Type = struct {
 
 pub const TypeWithHandle = struct {
     type: Type,
-    handle: *DocumentStore.Handle,
+    handle: *const DocumentStore.Handle,
 
     pub fn typeVal(node_handle: NodeWithHandle) TypeWithHandle {
         return .{
@@ -1080,7 +1080,7 @@ pub const TypeWithHandle = struct {
     }
 };
 
-pub fn resolveTypeOfNode(store: *DocumentStore, arena: *std.heap.ArenaAllocator, node_handle: NodeWithHandle) error{OutOfMemory}!?TypeWithHandle {
+pub fn resolveTypeOfNode(store: *const DocumentStore, arena: *std.heap.ArenaAllocator, node_handle: NodeWithHandle) error{OutOfMemory}!?TypeWithHandle {
     var bound_type_params = BoundTypeParams{};
     return resolveTypeOfNodeInternal(store, arena, node_handle, &bound_type_params);
 }
@@ -1145,7 +1145,7 @@ pub fn collectCImportNodes(allocator: std.mem.Allocator, tree: Ast) error{OutOfM
 
 pub const NodeWithHandle = struct {
     node: Ast.Node.Index,
-    handle: *DocumentStore.Handle,
+    handle: *const DocumentStore.Handle,
 };
 
 pub const FieldAccessReturn = struct {
@@ -1153,7 +1153,7 @@ pub const FieldAccessReturn = struct {
     unwrapped: ?TypeWithHandle = null,
 };
 
-pub fn getFieldAccessType(store: *DocumentStore, arena: *std.heap.ArenaAllocator, handle: *DocumentStore.Handle, source_index: usize, tokenizer: *std.zig.Tokenizer) !?FieldAccessReturn {
+pub fn getFieldAccessType(store: *const DocumentStore, arena: *std.heap.ArenaAllocator, handle: *const DocumentStore.Handle, source_index: usize, tokenizer: *std.zig.Tokenizer) !?FieldAccessReturn {
     var current_type = TypeWithHandle.typeVal(.{
         .node = undefined,
         .handle = handle,
@@ -1865,7 +1865,7 @@ pub const Declaration = union(enum) {
 
 pub const DeclWithHandle = struct {
     decl: *Declaration,
-    handle: *DocumentStore.Handle,
+    handle: *const DocumentStore.Handle,
 
     pub fn nameToken(self: DeclWithHandle) Ast.TokenIndex {
         const tree = self.handle.tree;
@@ -1887,7 +1887,7 @@ pub const DeclWithHandle = struct {
         };
     }
 
-    pub fn resolveType(self: DeclWithHandle, store: *DocumentStore, arena: *std.heap.ArenaAllocator, bound_type_params: *BoundTypeParams) !?TypeWithHandle {
+    pub fn resolveType(self: DeclWithHandle, store: *const DocumentStore, arena: *std.heap.ArenaAllocator, bound_type_params: *BoundTypeParams) !?TypeWithHandle {
         const tree = self.handle.tree;
         const node_tags = tree.nodes.items(.tag);
         const main_tokens = tree.nodes.items(.main_token);
@@ -1997,7 +1997,7 @@ fn findContainerScope(container_handle: NodeWithHandle) ?*Scope {
     } else null;
 }
 
-fn iterateSymbolsContainerInternal(store: *DocumentStore, arena: *std.heap.ArenaAllocator, container_handle: NodeWithHandle, orig_handle: *DocumentStore.Handle, comptime callback: anytype, context: anytype, instance_access: bool, use_trail: *std.ArrayList(Ast.Node.Index)) error{OutOfMemory}!void {
+fn iterateSymbolsContainerInternal(store: *const DocumentStore, arena: *std.heap.ArenaAllocator, container_handle: NodeWithHandle, orig_handle: *const DocumentStore.Handle, comptime callback: anytype, context: anytype, instance_access: bool, use_trail: *std.ArrayList(Ast.Node.Index)) error{OutOfMemory}!void {
     const container = container_handle.node;
     const handle = container_handle.handle;
 
@@ -2064,12 +2064,12 @@ fn iterateSymbolsContainerInternal(store: *DocumentStore, arena: *std.heap.Arena
     }
 }
 
-pub fn iterateSymbolsContainer(store: *DocumentStore, arena: *std.heap.ArenaAllocator, container_handle: NodeWithHandle, orig_handle: *DocumentStore.Handle, comptime callback: anytype, context: anytype, instance_access: bool) error{OutOfMemory}!void {
+pub fn iterateSymbolsContainer(store: *const DocumentStore, arena: *std.heap.ArenaAllocator, container_handle: NodeWithHandle, orig_handle: *const DocumentStore.Handle, comptime callback: anytype, context: anytype, instance_access: bool) error{OutOfMemory}!void {
     var use_trail = std.ArrayList(Ast.Node.Index).init(arena.allocator());
     return try iterateSymbolsContainerInternal(store, arena, container_handle, orig_handle, callback, context, instance_access, &use_trail);
 }
 
-pub fn iterateLabels(handle: *DocumentStore.Handle, source_index: usize, comptime callback: anytype, context: anytype) error{OutOfMemory}!void {
+pub fn iterateLabels(handle: *const DocumentStore.Handle, source_index: usize, comptime callback: anytype, context: anytype) error{OutOfMemory}!void {
     for (handle.document_scope.scopes.items) |scope| {
         if (source_index >= scope.loc.start and source_index < scope.loc.end) {
             var decl_it = scope.decls.iterator();
@@ -2085,7 +2085,7 @@ pub fn iterateLabels(handle: *DocumentStore.Handle, source_index: usize, comptim
     }
 }
 
-fn iterateSymbolsGlobalInternal(store: *DocumentStore, arena: *std.heap.ArenaAllocator, handle: *DocumentStore.Handle, source_index: usize, comptime callback: anytype, context: anytype, use_trail: *std.ArrayList(Ast.Node.Index)) error{OutOfMemory}!void {
+fn iterateSymbolsGlobalInternal(store: *const DocumentStore, arena: *std.heap.ArenaAllocator, handle: *const DocumentStore.Handle, source_index: usize, comptime callback: anytype, context: anytype, use_trail: *std.ArrayList(Ast.Node.Index)) error{OutOfMemory}!void {
     for (handle.document_scope.scopes.items) |scope| {
         if (source_index >= scope.loc.start and source_index <= scope.loc.end) {
             var decl_it = scope.decls.iterator();
@@ -2126,7 +2126,7 @@ fn iterateSymbolsGlobalInternal(store: *DocumentStore, arena: *std.heap.ArenaAll
     }
 }
 
-pub fn iterateSymbolsGlobal(store: *DocumentStore, arena: *std.heap.ArenaAllocator, handle: *DocumentStore.Handle, source_index: usize, comptime callback: anytype, context: anytype) error{OutOfMemory}!void {
+pub fn iterateSymbolsGlobal(store: *const DocumentStore, arena: *std.heap.ArenaAllocator, handle: *const DocumentStore.Handle, source_index: usize, comptime callback: anytype, context: anytype) error{OutOfMemory}!void {
     var use_trail = std.ArrayList(Ast.Node.Index).init(arena.allocator());
     return try iterateSymbolsGlobalInternal(store, arena, handle, source_index, callback, context, &use_trail);
 }
@@ -2151,7 +2151,7 @@ pub fn innermostBlockScope(handle: DocumentStore.Handle, source_index: usize) As
     return handle.document_scope.scopes.items[innermostBlockScopeIndex(handle, source_index)].toNodeIndex().?;
 }
 
-pub fn innermostContainer(handle: *DocumentStore.Handle, source_index: usize) TypeWithHandle {
+pub fn innermostContainer(handle: *const DocumentStore.Handle, source_index: usize) TypeWithHandle {
     var current = handle.document_scope.scopes.items[0].data.container;
     if (handle.document_scope.scopes.items.len == 1) return TypeWithHandle.typeVal(.{ .node = current, .handle = handle });
 
@@ -2167,7 +2167,7 @@ pub fn innermostContainer(handle: *DocumentStore.Handle, source_index: usize) Ty
     return TypeWithHandle.typeVal(.{ .node = current, .handle = handle });
 }
 
-fn resolveUse(store: *DocumentStore, arena: *std.heap.ArenaAllocator, uses: []const Ast.Node.Index, symbol: []const u8, handle: *DocumentStore.Handle) error{OutOfMemory}!?DeclWithHandle {
+fn resolveUse(store: *const DocumentStore, arena: *std.heap.ArenaAllocator, uses: []const Ast.Node.Index, symbol: []const u8, handle: *const DocumentStore.Handle) error{OutOfMemory}!?DeclWithHandle {
     // If we were asked to resolve this symbol before,
     // it is self-referential and we cannot resolve it.
     if (std.mem.indexOfScalar([*]const u8, using_trail.items, symbol.ptr) != null)
@@ -2199,7 +2199,7 @@ fn resolveUse(store: *DocumentStore, arena: *std.heap.ArenaAllocator, uses: []co
     return null;
 }
 
-pub fn lookupLabel(handle: *DocumentStore.Handle, symbol: []const u8, source_index: usize) error{OutOfMemory}!?DeclWithHandle {
+pub fn lookupLabel(handle: *const DocumentStore.Handle, symbol: []const u8, source_index: usize) error{OutOfMemory}!?DeclWithHandle {
     for (handle.document_scope.scopes.items) |scope| {
         if (source_index >= scope.loc.start and source_index < scope.loc.end) {
             if (scope.decls.getEntry(symbol)) |candidate| {
@@ -2218,7 +2218,7 @@ pub fn lookupLabel(handle: *DocumentStore.Handle, symbol: []const u8, source_ind
     return null;
 }
 
-pub fn lookupSymbolGlobal(store: *DocumentStore, arena: *std.heap.ArenaAllocator, handle: *DocumentStore.Handle, symbol: []const u8, source_index: usize) error{OutOfMemory}!?DeclWithHandle {
+pub fn lookupSymbolGlobal(store: *const DocumentStore, arena: *std.heap.ArenaAllocator, handle: *const DocumentStore.Handle, symbol: []const u8, source_index: usize) error{OutOfMemory}!?DeclWithHandle {
     const innermost_scope_idx = innermostBlockScopeIndex(handle.*, source_index);
 
     var curr = innermost_scope_idx;
@@ -2246,7 +2246,7 @@ pub fn lookupSymbolGlobal(store: *DocumentStore, arena: *std.heap.ArenaAllocator
 }
 
 pub fn lookupSymbolContainer(
-    store: *DocumentStore,
+    store: *const DocumentStore,
     arena: *std.heap.ArenaAllocator,
     container_handle: NodeWithHandle,
     symbol: []const u8,
diff --git a/src/code_actions.zig b/src/code_actions.zig
index b78b4b2..3161ff0 100644
--- a/src/code_actions.zig
+++ b/src/code_actions.zig
@@ -11,8 +11,8 @@ const offsets = @import("offsets.zig");
 
 pub const Builder = struct {
     arena: *std.heap.ArenaAllocator,
-    document_store: *DocumentStore,
-    handle: *DocumentStore.Handle,
+    document_store: *const DocumentStore,
+    handle: *const DocumentStore.Handle,
     offset_encoding: offsets.Encoding,
 
     pub fn generateCodeAction(
diff --git a/src/inlay_hints.zig b/src/inlay_hints.zig
index ad95c13..2c66e69 100644
--- a/src/inlay_hints.zig
+++ b/src/inlay_hints.zig
@@ -34,7 +34,7 @@ fn isNodeInRange(tree: Ast, node: Ast.Node.Index, range: types.Range) bool {
 const Builder = struct {
     allocator: std.mem.Allocator,
     config: *const Config,
-    handle: *DocumentStore.Handle,
+    handle: *const DocumentStore.Handle,
     hints: std.ArrayListUnmanaged(types.InlayHint),
     hover_kind: types.MarkupContent.Kind,
     encoding: offsets.Encoding,
@@ -81,7 +81,7 @@ const Builder = struct {
 /// `call` is the function call
 /// `decl_handle` should be a function protototype
 /// writes parameter hints into `builder.hints`
-fn writeCallHint(builder: *Builder, arena: *std.heap.ArenaAllocator, store: *DocumentStore, call: Ast.full.Call, decl_handle: analysis.DeclWithHandle) !void {
+fn writeCallHint(builder: *Builder, arena: *std.heap.ArenaAllocator, store: *const DocumentStore, call: Ast.full.Call, decl_handle: analysis.DeclWithHandle) !void {
     const handle = builder.handle;
     const tree = handle.tree;
 
@@ -181,7 +181,7 @@ fn writeBuiltinHint(builder: *Builder, parameters: []const Ast.Node.Index, argum
 }
 
 /// takes a Ast.full.Call (a function call), analysis its function expression, finds its declaration and writes parameter hints into `builder.hints`
-fn writeCallNodeHint(builder: *Builder, arena: *std.heap.ArenaAllocator, store: *DocumentStore, call: Ast.full.Call) !void {
+fn writeCallNodeHint(builder: *Builder, arena: *std.heap.ArenaAllocator, store: *const DocumentStore, call: Ast.full.Call) !void {
     if (call.ast.params.len == 0) return;
     if (builder.config.inlay_hints_exclude_single_argument and call.ast.params.len == 1) return;
 
@@ -257,7 +257,7 @@ fn callWriteNodeInlayHint(allocator: std.mem.Allocator, args: anytype) error{Out
 
 /// iterates over the ast and writes parameter hints into `builder.hints` for every function call and builtin call
 /// nodes outside the given range are excluded
-fn writeNodeInlayHint(builder: *Builder, arena: *std.heap.ArenaAllocator, store: *DocumentStore, maybe_node: ?Ast.Node.Index, range: types.Range) error{OutOfMemory}!void {
+fn writeNodeInlayHint(builder: *Builder, arena: *std.heap.ArenaAllocator, store: *const DocumentStore, maybe_node: ?Ast.Node.Index, range: types.Range) error{OutOfMemory}!void {
     const node = maybe_node orelse return;
 
     const handle = builder.handle;
@@ -688,8 +688,8 @@ fn writeNodeInlayHint(builder: *Builder, arena: *std.heap.ArenaAllocator, store:
 pub fn writeRangeInlayHint(
     arena: *std.heap.ArenaAllocator,
     config: Config,
-    store: *DocumentStore,
-    handle: *DocumentStore.Handle,
+    store: *const DocumentStore,
+    handle: *const DocumentStore.Handle,
     range: types.Range,
     hover_kind: types.MarkupContent.Kind,
     encoding: offsets.Encoding,
diff --git a/src/references.zig b/src/references.zig
index 6a8923a..b155955 100644
--- a/src/references.zig
+++ b/src/references.zig
@@ -56,11 +56,11 @@ pub fn labelReferences(
 const Builder = struct {
     arena: *std.heap.ArenaAllocator,
     locations: std.ArrayListUnmanaged(types.Location),
-    store: *DocumentStore,
+    store: *const DocumentStore,
     decl: analysis.DeclWithHandle,
     encoding: offsets.Encoding,
 
-    pub fn init(arena: *std.heap.ArenaAllocator, store: *DocumentStore, decl: analysis.DeclWithHandle, encoding: offsets.Encoding) Builder {
+    pub fn init(arena: *std.heap.ArenaAllocator, store: *const DocumentStore, decl: analysis.DeclWithHandle, encoding: offsets.Encoding) Builder {
         return Builder{
             .arena = arena,
             .locations = .{},
@@ -70,7 +70,7 @@ const Builder = struct {
         };
     }
 
-    pub fn add(self: *Builder, handle: *DocumentStore.Handle, token_index: Ast.TokenIndex) !void {
+    pub fn add(self: *Builder, handle: *const DocumentStore.Handle, token_index: Ast.TokenIndex) !void {
         try self.locations.append(self.arena.allocator(), .{
             .uri = handle.uri,
             .range = offsets.tokenToRange(handle.tree, token_index, self.encoding),
@@ -81,7 +81,7 @@ const Builder = struct {
 fn symbolReferencesInternal(
     builder: *Builder,
     node: Ast.Node.Index,
-    handle: *DocumentStore.Handle,
+    handle: *const DocumentStore.Handle,
 ) error{OutOfMemory}!void {
     const tree = handle.tree;
 
@@ -453,7 +453,7 @@ fn symbolReferencesInternal(
 
 pub fn symbolReferences(
     arena: *std.heap.ArenaAllocator,
-    store: *DocumentStore,
+    store: *const DocumentStore,
     decl_handle: analysis.DeclWithHandle,
     encoding: offsets.Encoding,
     include_decl: bool,
diff --git a/src/semantic_tokens.zig b/src/semantic_tokens.zig
index ab0bf10..244fd8f 100644
--- a/src/semantic_tokens.zig
+++ b/src/semantic_tokens.zig
@@ -52,14 +52,14 @@ pub const TokenModifiers = packed struct {
 
 const Builder = struct {
     arena: *std.heap.ArenaAllocator,
-    store: *DocumentStore,
-    handle: *DocumentStore.Handle,
+    store: *const DocumentStore,
+    handle: *const DocumentStore.Handle,
     previous_position: usize = 0,
     previous_token: ?Ast.TokenIndex = null,
     arr: std.ArrayListUnmanaged(u32),
     encoding: offsets.Encoding,
 
-    fn init(arena: *std.heap.ArenaAllocator, store: *DocumentStore, handle: *DocumentStore.Handle, encoding: offsets.Encoding) Builder {
+    fn init(arena: *std.heap.ArenaAllocator, store: *const DocumentStore, handle: *const DocumentStore.Handle, encoding: offsets.Encoding) Builder {
         return Builder{
             .arena = arena,
             .store = store,
@@ -223,7 +223,7 @@ fn writeDocComments(builder: *Builder, tree: Ast, doc: Ast.TokenIndex) !void {
     }
 }
 
-fn fieldTokenType(container_decl: Ast.Node.Index, handle: *DocumentStore.Handle) ?TokenType {
+fn fieldTokenType(container_decl: Ast.Node.Index, handle: *const DocumentStore.Handle) ?TokenType {
     const main_token = handle.tree.nodes.items(.main_token)[container_decl];
     if (main_token > handle.tree.tokens.len) return null;
     return @as(?TokenType, switch (handle.tree.tokens.items(.tag)[main_token]) {
@@ -1018,7 +1018,12 @@ fn writeContainerField(builder: *Builder, node: Ast.Node.Index, field_token_type
 }
 
 // TODO Range version, edit version.
-pub fn writeAllSemanticTokens(arena: *std.heap.ArenaAllocator, store: *DocumentStore, handle: *DocumentStore.Handle, encoding: offsets.Encoding) ![]u32 {
+pub fn writeAllSemanticTokens(
+    arena: *std.heap.ArenaAllocator,
+    store: *const DocumentStore,
+    handle: *const DocumentStore.Handle,
+    encoding: offsets.Encoding,
+) ![]u32 {
     var builder = Builder.init(arena, store, handle, encoding);
 
     // reverse the ast from the root declarations
diff --git a/src/signature_help.zig b/src/signature_help.zig
index 4b16170..2313984 100644
--- a/src/signature_help.zig
+++ b/src/signature_help.zig
@@ -8,7 +8,7 @@ const Token = std.zig.Token;
 const identifierFromPosition = @import("Server.zig").identifierFromPosition;
 const ast = @import("ast.zig");
 
-fn fnProtoToSignatureInfo(document_store: *DocumentStore, arena: *std.heap.ArenaAllocator, commas: u32, skip_self_param: bool, handle: *DocumentStore.Handle, fn_node: Ast.Node.Index, proto: Ast.full.FnProto) !types.SignatureInformation {
+fn fnProtoToSignatureInfo(document_store: *const DocumentStore, arena: *std.heap.ArenaAllocator, commas: u32, skip_self_param: bool, handle: *const DocumentStore.Handle, fn_node: Ast.Node.Index, proto: Ast.full.FnProto) !types.SignatureInformation {
     const ParameterInformation = types.SignatureInformation.ParameterInformation;
 
     const tree = handle.tree;
@@ -67,7 +67,7 @@ fn fnProtoToSignatureInfo(document_store: *DocumentStore, arena: *std.heap.Arena
     };
 }
 
-pub fn getSignatureInfo(document_store: *DocumentStore, arena: *std.heap.ArenaAllocator, handle: *DocumentStore.Handle, absolute_index: usize, comptime data: type) !?types.SignatureInformation {
+pub fn getSignatureInfo(document_store: *const DocumentStore, arena: *std.heap.ArenaAllocator, handle: *const DocumentStore.Handle, absolute_index: usize, comptime data: type) !?types.SignatureInformation {
     const innermost_block = analysis.innermostBlockScope(handle.*, absolute_index);
     const tree = handle.tree;
     const token_tags = tree.tokens.items(.tag);