diff --git a/src/ComptimeInterpreter.zig b/src/ComptimeInterpreter.zig
new file mode 100644
index 0000000..902d842
--- /dev/null
+++ b/src/ComptimeInterpreter.zig
@@ -0,0 +1,937 @@
+//! Hacky comptime interpreter, courtesy of midnight code run fuelled by spite;
+//! hope that one day this can use async... <33
+
+// TODO: builtin work!!
+// TODO: DODify
+// TODO: Work with DocumentStore
+
+const std = @import("std");
+const ast = @import("ast.zig");
+const zig = std.zig;
+const Ast = zig.Ast;
+const analysis = @import("analysis.zig");
+const DocumentStore = @import("DocumentStore.zig");
+const ComptimeInterpreter = @This();
+
+tree: Ast,
+root_scope: *InterpreterScope = undefined,
+allocator: std.mem.Allocator,
+
+type_info: std.ArrayListUnmanaged(TypeInfo) = .{},
+type_info_map: std.HashMapUnmanaged(TypeInfo, usize, TypeInfo.Context, std.hash_map.default_max_load_percentage) = .{},
+
+pub fn deinit(interpreter: *ComptimeInterpreter) void {
+    interpreter.type_info.deinit(interpreter.allocator);
+    interpreter.type_info_map.deinit(interpreter.allocator);
+}
+
+pub const TypeInfo = union(enum) {
+    pub const Context = struct {
+        interpreter: ComptimeInterpreter,
+        hasher: *std.hash.Wyhash,
+
+        pub fn hash(self: @This(), s: TypeInfo) u64 {
+            TypeInfo.hash(self, s);
+            return self.hasher.final();
+        }
+        pub fn eql(self: @This(), a: TypeInfo, b: TypeInfo) bool {
+            return TypeInfo.eql(self.interpreter, a, b);
+        }
+    };
+
+    pub const Signedness = enum { signed, unsigned };
+
+    pub const Struct = struct {
+        /// Declarations contained within
+        scope: *InterpreterScope,
+        fields: std.ArrayListUnmanaged(FieldDefinition) = .{},
+    };
+
+    pub const Int = struct {
+        bits: u16,
+        signedness: Signedness,
+    };
+
+    pub const Pointer = struct {
+        size: Size,
+        is_const: bool,
+        is_volatile: bool,
+        child: Type,
+        is_allowzero: bool,
+
+        sentinel: ?ValueData,
+
+        pub const Size = enum {
+            one,
+            many,
+            slice,
+            c,
+        };
+    };
+
+    pub const Fn = struct {
+        return_type: ?Type,
+        /// Index into interpreter.declarations
+        params: std.ArrayListUnmanaged(usize) = .{},
+    };
+
+    /// Hack to get anytype working; only valid on fnparams
+    @"anytype",
+    @"type",
+    @"bool",
+
+    @"struct": Struct,
+    pointer: Pointer,
+
+    int: Int,
+    @"comptime_int",
+    float: u16,
+    @"comptime_float",
+
+    pub fn eql(interpreter: ComptimeInterpreter, a: TypeInfo, b: TypeInfo) bool {
+        if (std.meta.activeTag(a) != std.meta.activeTag(b)) return false;
+        return switch (a) {
+            .@"struct" => false, // Struct declarations can never be equal
+            .pointer => p: {
+                const ap = a.pointer;
+                const bp = b.pointer;
+                break :p ap.size == bp.size and ap.is_const == bp.is_const and ap.is_volatile == bp.is_volatile and eql(
+                    interpreter,
+                    interpreter.typeToTypeInfo(ap.child),
+                    interpreter.typeToTypeInfo(bp.child),
+                ) and ap.is_allowzero == bp.is_allowzero and ((ap.sentinel == null and bp.sentinel == null) or ((ap.sentinel != null and bp.sentinel != null) and ap.sentinel.?.eql(bp.sentinel.?)));
+            },
+            .int => a.int.signedness == b.int.signedness and a.int.bits == b.int.bits,
+            .float => a.float == b.float,
+            else => return true,
+        };
+    }
+
+    pub fn hash(context: TypeInfo.Context, ti: TypeInfo) void {
+        context.hasher.update(&[_]u8{@enumToInt(ti)});
+        return switch (ti) {
+            .@"struct" => |s| {
+                context.hasher.update(std.mem.sliceAsBytes(s.fields.items));
+                // TODO: Fix
+                // context.hasher.update(std.mem.sliceAsBytes(s.declarations.items));
+            },
+            .pointer => |p| {
+                // const ap = a.pointer;
+                // const bp = b.pointer;
+                context.hasher.update(&[_]u8{ @enumToInt(p.size), @boolToInt(p.is_const), @boolToInt(p.is_volatile) });
+                TypeInfo.hash(context, context.interpreter.typeToTypeInfo(p.child));
+                context.hasher.update(&[_]u8{@boolToInt(p.is_allowzero)});
+                // TODO: Hash Sentinel
+                // break :p ap.size == bp.size and ap.is_const == bp.is_const and ap.is_volatile == bp.is_volatile and eql(
+                //     source_unit,
+                //     source_interpreter.type_info.items[ap.child.info_idx],
+                //     source_interpreter.type_info.items[bp.child.info_idx],
+                // ) and ap.is_allowzero == bp.is_allowzero and ((ap.sentinel == null and bp.sentinel == null) or ((ap.sentinel != null and bp.sentinel != null) and ap.sentinel.?.eql(bp.sentinel.?)));
+            },
+            .int => |i| {
+                // a.int.signedness == b.int.signedness and a.int.bits == b.int.bits;
+                context.hasher.update(&[_]u8{@enumToInt(i.signedness)});
+                context.hasher.update(&std.mem.toBytes(i.bits));
+            },
+            .float => |f| context.hasher.update(&std.mem.toBytes(f)),
+            else => {},
+        };
+    }
+};
+
+pub const Type = struct {
+    node_idx: Ast.Node.Index,
+    info_idx: usize,
+};
+
+pub const Value = struct {
+    node_idx: Ast.Node.Index,
+    @"type": Type,
+    value_data: ValueData,
+
+    pub fn eql(value: Value, other_value: Value) bool {
+        return value.value_data.eql(other_value.value_data);
+    }
+};
+
+pub const ValueData = union(enum) {
+    // TODO: Support larger ints, floats; bigints?
+
+    @"type": Type,
+    @"bool": bool,
+
+    // @"struct": struct {
+
+    // },
+    // one_ptr: *anyopaque,
+    /// TODO: Optimize this with an ArrayList that uses anyopaque slice
+    slice_ptr: std.ArrayListUnmanaged(ValueData),
+
+    @"comptime_int": std.math.big.int.Managed,
+    unsigned_int: u64,
+    signed_int: i64,
+    float: f64,
+
+    pub fn eql(data: ValueData, other_data: ValueData) bool {
+        if (std.meta.activeTag(data) != std.meta.activeTag(other_data)) return false;
+        // std.enums.
+        // std.meta.activeTag(u: anytype)
+        switch (data) {
+            .@"bool" => return data.@"bool" == other_data.@"bool",
+            .@"comptime_int" => return data.@"comptime_int".eq(other_data.@"comptime_int"),
+            .unsigned_int => return data.unsigned_int == other_data.unsigned_int,
+            .signed_int => return data.signed_int == other_data.signed_int,
+            .float => return data.float == other_data.float,
+            else => @panic("Simple eql not implemented!"),
+        }
+    }
+};
+
+pub const FieldDefinition = struct {
+    node_idx: Ast.Node.Index,
+    /// Store name so tree doesn't need to be used to access field name
+    name: []const u8,
+    @"type": Type,
+    default_value: ?Value,
+};
+
+pub const Declaration = struct {
+    node_idx: Ast.Node.Index,
+    /// Store name so tree doesn't need to be used to access declaration name
+    name: []const u8,
+    @"type": Type,
+    value: Value,
+
+    // TODO: figure this out
+    // pub const DeclarationKind = enum{variable, function};
+    // pub fn declarationKind(declaration: Declaration, tree: Ast) DeclarationKind {
+    //     return switch(tree.nodes.items(.tag)[declaration.node_idx]) {
+    //         .fn_proto,
+    //     .fn_proto_one,
+    //     .fn_proto_simple,
+    //     .fn_proto_multi,
+    //     .fn_decl
+    //     }
+    // }
+
+    pub fn isConstant(declaration: Declaration, tree: Ast) bool {
+        return switch (tree.nodes.items(.tag)[declaration.node_idx]) {
+            .global_var_decl,
+            .local_var_decl,
+            .aligned_var_decl,
+            .simple_var_decl,
+            => {
+                return tree.tokenSlice(ast.varDecl(tree, declaration.node_idx).?.ast.mut_token).len == 3;
+            },
+            else => false,
+        };
+    }
+};
+
+pub fn createType(interpreter: *ComptimeInterpreter, node_idx: Ast.Node.Index, type_info: TypeInfo) std.mem.Allocator.Error!Type {
+    // TODO: Figure out dedup
+    var hasher = std.hash.Wyhash.init(0);
+    var gpr = try interpreter.type_info_map.getOrPutContext(interpreter.allocator, type_info, .{ .interpreter = interpreter.*, .hasher = &hasher });
+
+    if (gpr.found_existing) {
+        // std.log.info("Deduplicating type {d}", .{interpreter.formatTypeInfo(unit.type_info.items[gpr.value_ptr.*])});
+        return Type{ .node_idx = node_idx, .info_idx = gpr.value_ptr.* };
+    } else {
+        try interpreter.type_info.append(interpreter.allocator, type_info);
+        const info_idx = interpreter.type_info.items.len - 1;
+        gpr.value_ptr.* = info_idx;
+        return Type{ .node_idx = node_idx, .info_idx = info_idx };
+    }
+}
+
+pub fn typeToTypeInfo(interpreter: ComptimeInterpreter, @"type": Type) TypeInfo {
+    return interpreter.type_info.items[@"type".info_idx];
+}
+
+pub const TypeInfoFormatter = struct {
+    interpreter: *ComptimeInterpreter,
+    ti: TypeInfo,
+
+    pub fn format(value: TypeInfoFormatter, comptime fmt: []const u8, options: std.fmt.FormatOptions, writer: anytype) !void {
+        _ = fmt;
+        _ = options;
+        return switch (value.ti) {
+            .int => |ii| switch (ii.signedness) {
+                .signed => try writer.print("i{d}", .{ii.bits}),
+                .unsigned => try writer.print("u{d}", .{ii.bits}),
+            }, // TODO
+            .float => |f| try writer.print("f{d}", .{f}),
+            .@"comptime_int" => try writer.writeAll("comptime_int"),
+            .@"comptime_float" => try writer.writeAll("comptime_float"),
+            .@"type" => try writer.writeAll("type"),
+            .@"bool" => try writer.writeAll("bool"),
+            .@"struct" => |s| {
+                try writer.writeAll("struct {");
+                var iterator = s.scope.declarations.iterator();
+                while (iterator.next()) |di| {
+                    const decl = di.value_ptr.*;
+                    if (decl.isConstant(value.interpreter.tree)) {
+                        try writer.print("const {s}: , {any}", .{ decl.name, value.interpreter.formatTypeInfo(value.interpreter.typeToTypeInfo(decl.@"type")) });
+                    } else {
+                        try writer.print("var {s}: , {any}", .{ decl.name, value.interpreter.formatTypeInfo(value.interpreter.typeToTypeInfo(decl.@"type")) });
+                    }
+                }
+                try writer.writeAll("}");
+            },
+            else => try writer.print("UnimplementedTypeInfoPrint", .{}),
+        };
+    }
+};
+
+pub fn formatTypeInfo(interpreter: *ComptimeInterpreter, ti: TypeInfo) TypeInfoFormatter {
+    return TypeInfoFormatter{ .interpreter = interpreter, .ti = ti };
+}
+
+pub const InterpreterScope = struct {
+    interpreter: *ComptimeInterpreter,
+
+    parent: ?*InterpreterScope = null,
+    node_idx: Ast.Node.Index,
+    declarations: std.StringHashMapUnmanaged(Declaration) = .{},
+    /// Resizes can modify element pointer locations, so we use a list of pointers
+    child_scopes: std.ArrayListUnmanaged(*InterpreterScope) = .{},
+
+    pub const ScopeKind = enum { container, block, function };
+    pub fn scopeKind(scope: InterpreterScope, tree: Ast) ScopeKind {
+        return switch (tree.nodes.items(.tag)[scope.node_idx]) {
+            .container_decl,
+            .container_decl_trailing,
+            .container_decl_arg,
+            .container_decl_arg_trailing,
+            .container_decl_two,
+            .container_decl_two_trailing,
+            .tagged_union,
+            .tagged_union_trailing,
+            .tagged_union_two,
+            .tagged_union_two_trailing,
+            .tagged_union_enum_tag,
+            .tagged_union_enum_tag_trailing,
+            .root,
+            .error_set_decl,
+            => .container,
+            else => .block,
+        };
+    }
+
+    pub fn getLabel(scope: InterpreterScope, tree: Ast) ?Ast.TokenIndex {
+        const token_tags = tree.tokens.items(.tag);
+
+        return switch (scope.scopeKind(tree)) {
+            .block => z: {
+                const lbrace = tree.nodes.items(.main_token)[scope.node_idx];
+                break :z if (token_tags[lbrace - 1] == .colon and token_tags[lbrace - 2] == .identifier)
+                    lbrace - 2
+                else
+                    null;
+            },
+            else => null,
+        };
+    }
+
+    pub const ParentScopeIterator = struct {
+        maybe_scope: ?*InterpreterScope,
+
+        pub fn next(psi: *ParentScopeIterator) ?*InterpreterScope {
+            if (psi.maybe_scope) |scope| {
+                const curr = scope;
+                psi.maybe_scope = scope.parent;
+                return curr;
+            } else return null;
+        }
+    };
+
+    pub fn parentScopeIterator(scope: *InterpreterScope) ParentScopeIterator {
+        return ParentScopeIterator{ .maybe_scope = scope };
+    }
+
+    pub fn deinit(scope: *InterpreterScope) void {
+        scope.declarations.deinit(scope.interpreter.allocator);
+        for (scope.child_scopes.items) |child| child.deinit();
+        scope.child_scopes.deinit(scope.interpreter.allocator);
+
+        scope.interpreter.allocator.destroy(scope);
+    }
+};
+
+pub fn newScope(interpreter: *ComptimeInterpreter, maybe_parent: ?*InterpreterScope, node_idx: Ast.Node.Index) std.mem.Allocator.Error!*InterpreterScope {
+    var ls = try interpreter.allocator.create(InterpreterScope);
+    if (maybe_parent) |parent| try parent.child_scopes.append(interpreter.allocator, ls);
+    ls.* = .{
+        .interpreter = interpreter,
+        .parent = maybe_parent,
+        .node_idx = node_idx,
+    };
+    return ls;
+}
+
+pub const InterpretResult = union(enum) {
+    @"break": ?[]const u8,
+    break_with_value: struct {
+        label: ?[]const u8,
+        value: Value,
+    },
+    value: Value,
+    @"return",
+    return_with_value: Value,
+    nothing,
+
+    pub fn maybeGetValue(result: InterpretResult) ?Value {
+        return switch (result) {
+            .break_with_value => |v| v.value,
+            .value => |v| v,
+            else => null,
+        };
+    }
+
+    pub fn getValue(result: InterpretResult) Value {
+        return result.maybeGetValue() orelse @panic("Attempted to get value from non-value interpret result");
+    }
+};
+
+// Might be useful in the future
+pub const InterpretOptions = struct {};
+
+pub const InterpretError = std.mem.Allocator.Error || std.fmt.ParseIntError || std.fmt.ParseFloatError || error{ InvalidCharacter, InvalidBase };
+pub fn interpret(
+    interpreter: *ComptimeInterpreter,
+    node_idx: Ast.Node.Index,
+    scope: ?*InterpreterScope,
+    options: InterpretOptions,
+) InterpretError!InterpretResult {
+    // _ = unit;
+    // _ = node;
+    // _ = observe_values;
+
+    const tree = interpreter.tree;
+    const tags = tree.nodes.items(.tag);
+    const data = tree.nodes.items(.data);
+    const main_tokens = tree.nodes.items(.main_token);
+
+    std.log.info("{any}", .{tags[node_idx]});
+
+    switch (tags[node_idx]) {
+        .container_decl,
+        .container_decl_trailing,
+        .container_decl_arg,
+        .container_decl_arg_trailing,
+        .container_decl_two,
+        .container_decl_two_trailing,
+        .tagged_union,
+        .tagged_union_trailing,
+        .tagged_union_two,
+        .tagged_union_two_trailing,
+        .tagged_union_enum_tag,
+        .tagged_union_enum_tag_trailing,
+        .root,
+        .error_set_decl,
+        => {
+            var container_scope = try interpreter.newScope(scope, node_idx);
+            var type_info = TypeInfo{
+                .@"struct" = .{
+                    .scope = container_scope,
+                },
+            };
+
+            if (node_idx == 0) interpreter.root_scope = container_scope;
+
+            var buffer: [2]Ast.Node.Index = undefined;
+            const members = ast.declMembers(tree, node_idx, &buffer);
+
+            for (members) |member| {
+                const maybe_container_field: ?zig.Ast.full.ContainerField = switch (tags[member]) {
+                    .container_field => tree.containerField(member),
+                    .container_field_align => tree.containerFieldAlign(member),
+                    .container_field_init => tree.containerFieldInit(member),
+                    else => null,
+                };
+
+                if (maybe_container_field) |field_info| {
+                    var init_type = try interpreter.interpret(field_info.ast.type_expr, container_scope, .{});
+                    var default_value = if (field_info.ast.value_expr == 0)
+                        null
+                    else
+                        (try interpreter.interpret(field_info.ast.value_expr, container_scope, .{})).getValue();
+
+                    const name = tree.tokenSlice(field_info.ast.name_token);
+                    const field = FieldDefinition{
+                        .node_idx = member,
+                        .name = name,
+                        .@"type" = init_type.getValue().value_data.@"type",
+                        .default_value = default_value,
+                        // TODO: Default values
+                        // .@"type" = T: {
+                        //     var value = (try interpreter.interpret(field_info.ast.type_expr, scope_idx, true)).?.value;
+                        //     break :T @ptrCast(*Type, @alignCast(@alignOf(*Type), value)).*;
+                        // },
+                        // .value = null,
+                    };
+
+                    try type_info.@"struct".fields.append(interpreter.allocator, field);
+                } else {
+                    _ = try interpreter.interpret(member, container_scope, options);
+                }
+            }
+
+            return InterpretResult{ .value = Value{
+                .node_idx = node_idx,
+                .@"type" = try interpreter.createType(node_idx, .{ .@"type" = .{} }),
+                .value_data = .{ .@"type" = try interpreter.createType(node_idx, type_info) },
+            } };
+        },
+        .global_var_decl,
+        .local_var_decl,
+        .aligned_var_decl,
+        .simple_var_decl,
+        => {
+            const decl = ast.varDecl(tree, node_idx).?;
+            var value = (try interpreter.interpret(decl.ast.init_node, scope, options)).getValue();
+            var @"type" = if (decl.ast.type_node == 0) Value{
+                .node_idx = std.math.maxInt(Ast.Node.Index),
+                .@"type" = try interpreter.createType(node_idx, .{ .@"type" = .{} }),
+                .value_data = .{ .@"type" = value.@"type" },
+            } else (try interpreter.interpret(decl.ast.type_node, scope, options)).getValue();
+
+            const name = analysis.getDeclName(tree, node_idx).?;
+            try scope.?.declarations.put(interpreter.allocator, name, .{
+                .node_idx = node_idx,
+                .name = name,
+                .@"type" = @"type".value_data.@"type",
+                .@"value" = value,
+            });
+
+            return InterpretResult{ .nothing = .{} };
+        },
+        .block,
+        .block_semicolon,
+        .block_two,
+        .block_two_semicolon,
+        => {
+            // try interpreter.scopes.append(interpreter.allocator, .{
+            //     .node_idx = node_idx,
+            //     .parent_scope = parent_scope_idx orelse std.math.maxInt(usize),
+            // });
+            // const scope_idx = interpreter.scopes.items.len - 1;
+
+            var block_scope = try interpreter.newScope(scope, node_idx);
+
+            var buffer: [2]Ast.Node.Index = undefined;
+            const statements = ast.blockStatements(tree, node_idx, &buffer).?;
+
+            for (statements) |idx| {
+                const ret = try interpreter.interpret(idx, block_scope, options);
+                switch (ret) {
+                    .@"break" => |lllll| {
+                        const maybe_block_label_string = if (scope.?.getLabel(tree)) |i| tree.tokenSlice(i) else null;
+                        if (lllll) |l| {
+                            if (maybe_block_label_string) |ls| {
+                                if (std.mem.eql(u8, l, ls)) {
+                                    return InterpretResult{ .nothing = .{} };
+                                } else return ret;
+                            } else return ret;
+                        } else {
+                            return InterpretResult{ .nothing = .{} };
+                        }
+                    },
+                    .break_with_value => |bwv| {
+                        const maybe_block_label_string = if (scope.?.getLabel(tree)) |i| tree.tokenSlice(i) else null;
+
+                        if (bwv.label) |l| {
+                            if (maybe_block_label_string) |ls| {
+                                if (std.mem.eql(u8, l, ls)) {
+                                    return InterpretResult{ .value = bwv.value };
+                                } else return ret;
+                            } else return ret;
+                        } else {
+                            return InterpretResult{ .value = bwv.value };
+                        }
+                    },
+                    .@"return", .return_with_value => return ret,
+                    else => {},
+                }
+            }
+
+            return InterpretResult{ .nothing = .{} };
+        },
+        .identifier => {
+            var value = tree.getNodeSource(node_idx);
+
+            if (std.mem.eql(u8, "type", value)) {
+                return InterpretResult{ .value = Value{
+                    .node_idx = node_idx,
+                    .@"type" = try interpreter.createType(node_idx, .{ .@"type" = .{} }),
+                    .value_data = .{ .@"type" = try interpreter.createType(node_idx, .{ .@"type" = .{} }) },
+                } };
+            } else if (value.len >= 2 and (value[0] == 'u' or value[0] == 'i')) int: {
+                return InterpretResult{ .value = Value{
+                    .node_idx = node_idx,
+                    .@"type" = try interpreter.createType(node_idx, .{ .@"type" = .{} }),
+                    .value_data = .{ .@"type" = try interpreter.createType(node_idx, .{
+                        .int = .{
+                            .signedness = if (value[0] == 'u') .unsigned else .signed,
+                            .bits = std.fmt.parseInt(u16, value[1..], 10) catch break :int,
+                        },
+                    }) },
+                } };
+            }
+
+            // Logic to find identifiers in accessible scopes
+
+            var psi = scope.?.parentScopeIterator();
+            while (psi.next()) |pscope| {
+                return InterpretResult{ .value = (pscope.declarations.get(value) orelse continue).value };
+            }
+
+            std.log.err("Identifier not found: {s}", .{value});
+            @panic("Could not find identifier");
+        },
+        .grouped_expression => {
+            return try interpreter.interpret(data[node_idx].lhs, scope, options);
+        },
+        .@"break" => {
+            const label = if (data[node_idx].lhs == 0) null else tree.tokenSlice(data[node_idx].lhs);
+            return if (data[node_idx].rhs == 0)
+                InterpretResult{ .@"break" = label }
+            else
+                InterpretResult{ .break_with_value = .{ .label = label, .value = (try interpreter.interpret(data[node_idx].rhs, scope, options)).getValue() } };
+        },
+        .@"return" => {
+            return if (data[node_idx].lhs == 0)
+                InterpretResult{ .@"return" = {} }
+            else
+                InterpretResult{ .return_with_value = (try interpreter.interpret(data[node_idx].lhs, scope, options)).getValue() };
+        },
+        .@"if", .if_simple => {
+            const iff = ast.ifFull(tree, node_idx);
+            // TODO: Don't evaluate runtime ifs
+            // if (options.observe_values) {
+            const ir = try interpreter.interpret(iff.ast.cond_expr, scope, options);
+            if (ir.getValue().value_data.@"bool") {
+                return try interpreter.interpret(iff.ast.then_expr, scope, options);
+            } else {
+                if (iff.ast.else_expr != 0) {
+                    return try interpreter.interpret(iff.ast.else_expr, scope, options);
+                } else return InterpretResult{ .nothing = .{} };
+            }
+            // } else {
+            //     _ = try interpreter.interpret(iff.ast.cond_expr, scope, options);
+            //     _ = try interpreter.interpret(iff.ast.then_expr, scope, options);
+            //     _ = try interpreter.interpret(iff.ast.else_expr, scope, options);
+            // }
+            @panic("bruh");
+        },
+        .equal_equal => {
+            var a = try interpreter.interpret(data[node_idx].lhs, scope, options);
+            var b = try interpreter.interpret(data[node_idx].rhs, scope, options);
+            return InterpretResult{ .value = Value{
+                .node_idx = node_idx,
+                .@"type" = try interpreter.createType(node_idx, .{ .@"bool" = .{} }),
+                .value_data = .{ .@"bool" = a.getValue().eql(b.getValue()) },
+            } };
+            // a.getValue().eql(b.getValue())
+        },
+        .number_literal => {
+            const s = tree.getNodeSource(node_idx);
+            const nl = std.zig.parseNumberLiteral(s);
+            // if (nl == .failure) ;
+            return InterpretResult{ .value = Value{
+                .node_idx = node_idx,
+                .@"type" = try interpreter.createType(node_idx, .{ .@"comptime_int" = .{} }),
+                .value_data = switch (nl) {
+                    .float => .{ .float = try std.fmt.parseFloat(f64, s) },
+                    .int => if (s[0] == '-') ValueData{ .signed_int = try std.fmt.parseInt(i64, s, 0) } else ValueData{ .unsigned_int = try std.fmt.parseInt(u64, s, 0) },
+                    .big_int => |bii| ppp: {
+                        var bi = try std.math.big.int.Managed.init(interpreter.allocator);
+                        try bi.setString(@enumToInt(bii), s[if (bii != .decimal) @as(usize, 2) else @as(usize, 0)..]);
+                        break :ppp .{ .@"comptime_int" = bi };
+                    },
+                    .failure => @panic("Failed to parse number literal"),
+                },
+            } };
+        },
+        .assign,
+        .assign_bit_and,
+        .assign_bit_or,
+        .assign_shl,
+        .assign_shr,
+        .assign_bit_xor,
+        .assign_div,
+        .assign_sub,
+        .assign_sub_wrap,
+        .assign_mod,
+        .assign_add,
+        .assign_add_wrap,
+        .assign_mul,
+        .assign_mul_wrap,
+        => {
+            // TODO: Make this work with non identifiers
+            // TODO: Actually consider operators
+
+            const value = tree.getNodeSource(data[node_idx].lhs);
+
+            var psi = scope.?.parentScopeIterator();
+            while (psi.next()) |pscope| {
+                if (pscope.declarations.getEntry(value)) |decl|
+                    decl.value_ptr.value = (try interpreter.interpret(data[node_idx].rhs, scope.?, options)).getValue();
+            }
+
+            return InterpretResult{ .nothing = .{} };
+        },
+        // .@"switch",
+        // .switch_comma,
+        // => {
+        //     const cond = data[node_idx].lhs;
+        //     const extra = tree.extraData(data[node_idx].rhs, Ast.Node.SubRange);
+        //     const cases = tree.extra_data[extra.start..extra.end];
+
+        //     for (cases) |case| {
+        //         const switch_case: Ast.full.SwitchCase = switch (tags[case]) {
+        //             .switch_case => tree.switchCase(case),
+        //             .switch_case_one => tree.switchCaseOne(case),
+        //             else => continue,
+        //         };
+        //     }
+        // },
+        .builtin_call,
+        .builtin_call_comma,
+        .builtin_call_two,
+        .builtin_call_two_comma,
+        => {
+            var buffer: [2]Ast.Node.Index = undefined;
+            const params = ast.builtinCallParams(tree, node_idx, &buffer).?;
+            const call_name = tree.tokenSlice(main_tokens[node_idx]);
+
+            if (std.mem.eql(u8, call_name, "@compileLog")) {
+                pp: for (params) |param| {
+                    const res = (try interpreter.interpret(param, scope, .{})).getValue();
+                    const ti = interpreter.type_info.items[res.@"type".info_idx];
+                    switch (ti) {
+                        .pointer => |ptr| {
+                            const child = interpreter.type_info.items[ptr.child.info_idx];
+                            if (ptr.size == .slice and child == .int and child.int.bits == 8 and child.int.signedness == .unsigned) {
+
+                                // TODO: Fix once I optimize slices
+                                std.debug.print("@compileLog output: ", .{});
+                                for (res.value_data.slice_ptr.items) |i| std.debug.print("{c}", .{@truncate(u8, i.unsigned_int)});
+                                std.debug.print("\n", .{});
+
+                                break :pp;
+                            }
+                        },
+                        else => {},
+                    }
+
+                    @panic("compileLog argument type not printable!");
+                }
+
+                return InterpretResult{ .nothing = .{} };
+            }
+
+            std.log.info("Builtin not implemented: {s}", .{call_name});
+            @panic("Builtin not implemented");
+        },
+        .string_literal => {
+            const value = tree.getNodeSource(node_idx)[1 .. tree.getNodeSource(node_idx).len - 1];
+            var val = Value{
+                .node_idx = node_idx,
+                .@"type" = try interpreter.createType(node_idx, .{
+                    .pointer = .{
+                        .size = .slice,
+                        .is_const = true,
+                        .is_volatile = false,
+                        .child = try interpreter.createType(0, .{ .int = .{
+                            .bits = 8,
+                            .signedness = .unsigned,
+                        } }),
+                        .is_allowzero = false,
+
+                        .sentinel = .{ .unsigned_int = 0 },
+                    },
+                }),
+                .value_data = .{ .slice_ptr = .{} },
+            };
+
+            for (value) |z| {
+                try val.value_data.slice_ptr.append(interpreter.allocator, .{ .unsigned_int = z });
+            }
+            try val.value_data.slice_ptr.append(interpreter.allocator, .{ .unsigned_int = 0 });
+
+            return InterpretResult{ .value = val };
+        },
+        // TODO: Add comptime autodetection; e.g. const MyArrayList = std.ArrayList(u8)
+        .@"comptime" => {
+            return try interpreter.interpret(data[node_idx].lhs, scope, .{});
+        },
+        // .fn_proto,
+        // .fn_proto_multi,
+        // .fn_proto_one,
+        // .fn_proto_simple,
+        .fn_decl => {
+            // var buf: [1]Ast.Node.Index = undefined;
+            // const func = ast.fnProto(tree, node_idx, &buf).?;
+
+            // TODO: Add params
+
+            // var type_info = TypeInfo{
+            //     .@"fn" = .{
+            //         .definition_scope = scope.?,
+            //         .node_idx = node_idx,
+            //     },
+            // };
+
+            // var it = func.iterate(&tree);
+            // while (ast.nextFnParam(&it)) |param| {
+            //     // Add parameter decls
+            //     if (param.name_token) |name_token| {
+            //         // TODO: Think of new method for functions
+            //         if ((try interpreter.interpret(param.type_expr, func_scope_idx, .{ .observe_values = true, .is_comptime = true })).maybeGetValue()) |value| {
+            //             try interpreter.addDeclaration(func_scope_idx, value.value_data.@"type");
+            //             try fnd.params.append(interpreter.allocator, interpreter.declarations.items.len - 1);
+            //         } else {
+            //             try interpreter.addDeclaration(parent_scope_idx.?, .{
+            //                 .node_idx = node_idx,
+            //                 .name = tree.tokenSlice(name_token),
+            //                 .scope_idx = func_scope_idx, // orelse std.math.maxInt(usize),
+            //                 .@"value" = undefined,
+            //                 .@"type" = interpreter.createType(0, .{ .@"anytype" = .{} }),
+            //             });
+            //             try fnd.params.append(interpreter.allocator, interpreter.declarations.items.len - 1);
+            //         }
+            //     }
+            // }
+
+            // if ((try interpreter.interpret(func.ast.return_type, func_scope_idx, .{ .observe_values = true, .is_comptime = true })).maybeGetValue()) |value|
+            //     fnd.return_type = value.value_data.@"type";
+
+            // var value = Value{
+            //     .node_idx = node_idx,
+            //     .@"type" = try interpreter.createType(node_idx, type_info),
+            //     .value_data = .{ .@"fn" = .{} },
+            // };
+
+            // const name = ast.getDeclName(tree, node_idx).?;
+            // try scope.?.declarations.put(interpreter.allocator, name, .{
+            //     .node_idx = node_idx,
+            //     .name = name,
+            //     .@"type" = value.@"type",
+            //     .@"value" = value,
+            // });
+
+            return InterpretResult{ .nothing = .{} };
+        },
+        .call,
+        .call_comma,
+        .async_call,
+        .async_call_comma,
+        .call_one,
+        .call_one_comma,
+        .async_call_one,
+        .async_call_one_comma,
+        => {
+            // var params: [1]Ast.Node.Index = undefined;
+            // const call = ast.callFull(tree, node_idx, &params) orelse unreachable;
+
+            // const callee = .{ .node = call.ast.fn_expr, .handle = handle };
+            // const decl = (try resolveTypeOfNodeInternal(store, arena, callee, bound_type_params)) orelse
+            //     return null;
+
+            // if (decl.type.is_type_val) return null;
+            // const decl_node = switch (decl.type.data) {
+            //     .other => |n| n,
+            //     else => return null,
+            // };
+            // var buf: [1]Ast.Node.Index = undefined;
+            // const func_maybe = ast.fnProto(decl.handle.tree, decl_node, &buf);
+
+            // if (func_maybe) |fn_decl| {
+            //     var expected_params = fn_decl.ast.params.len;
+            //     // If we call as method, the first parameter should be skipped
+            //     // TODO: Back-parse to extract the self argument?
+            //     var it = fn_decl.iterate(&decl.handle.tree);
+            //     if (token_tags[call.ast.lparen - 2] == .period) {
+            //         if (try hasSelfParam(arena, store, decl.handle, fn_decl)) {
+            //             _ = ast.nextFnParam(&it);
+            //             expected_params -= 1;
+            //         }
+            //     }
+
+            //     // Bind type params to the arguments passed in the call.
+            //     const param_len = std.math.min(call.ast.params.len, expected_params);
+            //     var i: usize = 0;
+            //     while (ast.nextFnParam(&it)) |decl_param| : (i += 1) {
+            //         if (i >= param_len) break;
+            //         if (!isMetaType(decl.handle.tree, decl_param.type_expr))
+            //             continue;
+
+            //         const argument = .{ .node = call.ast.params[i], .handle = handle };
+            //         const argument_type = (try resolveTypeOfNodeInternal(
+            //             store,
+            //             arena,
+            //             argument,
+            //             bound_type_params,
+            //         )) orelse
+            //             continue;
+            //         if (!argument_type.type.is_type_val) continue;
+
+            //         try bound_type_params.put(arena.allocator(), decl_param, argument_type);
+            //     }
+
+            //     const has_body = decl.handle.tree.nodes.items(.tag)[decl_node] == .fn_decl;
+            //     const body = decl.handle.tree.nodes.items(.data)[decl_node].rhs;
+            //     return try resolveReturnType(store, arena, fn_decl, decl.handle, bound_type_params, if (has_body) body else null);
+            // }
+            // return null;
+            return InterpretResult{ .nothing = .{} };
+        },
+        else => {
+            std.log.err("Unhandled {any}", .{tags[node_idx]});
+            return InterpretResult{ .nothing = .{} };
+        },
+    }
+}
+
+pub const CallResult = struct {
+    scope: *InterpreterScope,
+    result: union(enum) {
+        value: Value,
+        nothing,
+    },
+};
+
+pub fn call(
+    interpreter: *ComptimeInterpreter,
+    func_node_idx: Ast.Node.Index,
+    arguments: []const Value,
+    options: InterpretOptions,
+) InterpretError!CallResult {
+    // TODO: Eval, check parameter types
+
+    // TODO: Arguments
+    _ = options;
+    _ = arguments;
+
+    const tree = interpreter.tree;
+    const tags = tree.nodes.items(.tag);
+
+    std.debug.assert(tags[func_node_idx] == .fn_decl);
+
+    // TODO: Parent sc]ope exploration (consts, typefuncs, etc.)
+    var fn_scope = try interpreter.newScope(null, func_node_idx);
+
+    const body = tree.nodes.items(.data)[func_node_idx].rhs;
+    const result = try interpreter.interpret(body, fn_scope, .{});
+
+    // TODO: Defers
+    return CallResult{
+        .scope = fn_scope,
+        .result = switch (result) {
+            .@"return" => .{ .nothing = {} },
+            .@"return_with_value" => |v| .{ .value = v },
+            else => @panic("bruh"),
+        },
+    };
+}
diff --git a/src/analysis.zig b/src/analysis.zig
index 7da2747..2e35540 100644
--- a/src/analysis.zig
+++ b/src/analysis.zig
@@ -306,7 +306,7 @@ pub fn getDeclNameToken(tree: Ast, node: Ast.Node.Index) ?Ast.TokenIndex {
     };
 }
 
-fn getDeclName(tree: Ast, node: Ast.Node.Index) ?[]const u8 {
+pub fn getDeclName(tree: Ast, node: Ast.Node.Index) ?[]const u8 {
     const name = tree.tokenSlice(getDeclNameToken(tree, node) orelse return null);
     return switch (tree.nodes.items(.tag)[node]) {
         .test_decl => name[1 .. name.len - 1],
diff --git a/src/zls.zig b/src/zls.zig
index c896309..40920b2 100644
--- a/src/zls.zig
+++ b/src/zls.zig
@@ -8,3 +8,4 @@ pub const Server = @import("Server.zig");
 pub const translate_c = @import("translate_c.zig");
 pub const types = @import("types.zig");
 pub const URI = @import("uri.zig");
+pub const ComptimeInterpreter = @import("ComptimeInterpreter.zig");
diff --git a/tests/language_features/comptime_interpreter.zig b/tests/language_features/comptime_interpreter.zig
new file mode 100644
index 0000000..d08d777
--- /dev/null
+++ b/tests/language_features/comptime_interpreter.zig
@@ -0,0 +1,26 @@
+const std = @import("std");
+const zls = @import("zls");
+
+const Ast = std.zig.Ast;
+
+const ComptimeInterpreter = zls.ComptimeInterpreter;
+
+const allocator: std.mem.Allocator = std.testing.allocator;
+
+test "ComptimeInterpreter - basic test" {
+    var tree = try std.zig.parse(allocator,
+        \\pub fn ReturnMyType() type {
+        \\    if (1 == 1) return u69;
+        \\    return u8;
+        \\}
+    );
+    defer tree.deinit(allocator);
+
+    var interpreter = ComptimeInterpreter{ .tree = tree, .allocator = allocator };
+    defer interpreter.deinit();
+
+    const z = try interpreter.call(tree.rootDecls()[0], &.{}, .{});
+    defer z.scope.deinit();
+
+    try std.testing.expectFmt("u69", "{any}", .{interpreter.formatTypeInfo(interpreter.typeToTypeInfo(z.result.value.value_data.@"type"))});
+}
diff --git a/tests/tests.zig b/tests/tests.zig
index c1772cb..93efef6 100644
--- a/tests/tests.zig
+++ b/tests/tests.zig
@@ -1,20 +1,21 @@
 comptime {
     _ = @import("helper.zig");
 
-    _ = @import("utility/offsets.zig");
-    _ = @import("utility/position_context.zig");
-    _ = @import("utility/uri.zig");
+    // _ = @import("utility/offsets.zig");
+    // _ = @import("utility/position_context.zig");
+    // _ = @import("utility/uri.zig");
 
-    // TODO Lifecycle Messages
+    // // TODO Lifecycle Messages
 
-    // TODO Document Synchronization
+    // // TODO Document Synchronization
 
-    // LSP features
-    _ = @import("lsp_features/semantic_tokens.zig");
-    _ = @import("lsp_features/inlay_hints.zig");
-    _ = @import("lsp_features/references.zig");
-    _ = @import("lsp_features/completion.zig");
+    // // LSP features
+    // _ = @import("lsp_features/semantic_tokens.zig");
+    // _ = @import("lsp_features/inlay_hints.zig");
+    // _ = @import("lsp_features/references.zig");
+    // _ = @import("lsp_features/completion.zig");
 
     // Language features
-    _ = @import("language_features/cimport.zig");
+    // _ = @import("language_features/cimport.zig");
+    _ = @import("language_features/comptime_interpreter.zig");
 }