diff --git a/cmd/src/tools/cmd_fmt.ri b/cmd/src/tools/cmd_fmt.ri
index c6d531651..960dd9cf2 100644
--- a/cmd/src/tools/cmd_fmt.ri
+++ b/cmd/src/tools/cmd_fmt.ri
@@ -1,5 +1,5 @@
-// Copyright (C) 2023-present Jose Mendoza - All rights reserved. Use of this 
-// source code is governed by an MIT license that can be found in the LICENSE 
+// Copyright (C) 2023-present Jose Mendoza - All rights reserved. Use of this
+// source code is governed by an MIT license that can be found in the LICENSE
 // file.
 
 import std/flag;
@@ -15,7 +15,7 @@ import rivet/parser;
 var fmt_desc := "Formats the given Rivet source files or recursively formats all files in the
 directory, then prints their formatted source to stdout.";
 
-pub func cmd_fmt(args: []string) -> ! {
+pub func cmd_fmt(args: [:]string) -> ! {
     mut fp := flag.FlagParser.new(args);
     fp.set_application_name("rivet fmt");
     fp.set_arguments_description("[FILES|DIRECTORIES]");
diff --git a/cmd/src/tools/cmd_new.ri b/cmd/src/tools/cmd_new.ri
index 71e99846a..c640f61c3 100644
--- a/cmd/src/tools/cmd_new.ri
+++ b/cmd/src/tools/cmd_new.ri
@@ -29,7 +29,7 @@ var available_templates := "Available templates:
    bin          A simple binary project (default).
    lib          A simple library project.";
 
-pub func cmd_new(args: []string, is_init: bool) -> ! {
+pub func cmd_new(args: [:]string, is_init: bool) -> ! {
     mut template := "";
     mut fp := flag.FlagParser.new(args);
     if is_init {
diff --git a/lib/core/src/Slice.ri b/lib/core/src/Slice.ri
new file mode 100644
index 000000000..8e2028949
--- /dev/null
+++ b/lib/core/src/Slice.ri
@@ -0,0 +1,71 @@
+// Copyright (C) 2023-present Jose Mendoza - All rights reserved. Use of this
+// source code is governed by an MIT license that can be found in the LICENSE
+// file.
+
+struct Slice {
+    ptr: rawptr;
+    elem_size: uint;
+    len: uint;
+
+    func get(&self, idx: uint) -> rawptr {
+        if idx >= self.len {
+            runtime_error("dynamic array index out of range (index: {}, len: {})", idx, self.len);
+        }
+        return unsafe { @ptr_add(@as([&]mut uint8, self.ptr), idx * self.elem_size) };
+    }
+
+    func set(&self, idx: uint, val: rawptr) {
+        if idx >= self.len {
+            runtime_error("dynamic array index out of range (index: {}, len: {})", idx, self.len);
+        }
+        unsafe {
+            mem_copy(
+                @ptr_add(@as([&]mut uint8, self.ptr), self.elem_size * idx),
+                val, self.elem_size
+            );
+        }
+    }
+
+    #[inline]
+    func is_empty(&self) -> bool {
+        return self.len == 0;
+    }
+
+    func slice(self, start: uint, end: uint) -> Self {
+        if start > end || end > self.len {
+            runtime_error(
+                "slice index [{}:{}] out of range (len: {})", start, end, self.len
+            );
+        }
+        len := end - start;
+        if len == self.len {
+            return Self(self.ptr, self.elem_size, self.len);
+        }
+        return Self(
+            unsafe { @ptr_add(@as([&]mut uint8, self.ptr), start * self.elem_size) },
+            self.elem_size, len
+        );
+    }
+
+    #[inline]
+    func slice_from(self, start: uint) -> Self {
+        return self.slice(start, self.len);
+    }
+
+    #[inline]
+    func to_dynamic_array(&self) -> DynArray {
+        return unsafe { DynArray.from_array(self.ptr, self.elem_size, self.len) };
+    }
+
+    func ==(&self, rhs: &Self) -> bool {
+        if self.len != rhs.len {
+            return false;
+        }
+        return mem_cmp(self.ptr, rhs.ptr, self.len) == 0;
+    }
+
+    #[inline]
+    func !=(&self, rhs: &Self) -> bool {
+        return !(self == rhs);
+    }
+}
diff --git a/lib/core/src/StringBuilder.c.ri b/lib/core/src/StringBuilder.c.ri
index 4055843b9..060b94865 100644
--- a/lib/core/src/StringBuilder.c.ri
+++ b/lib/core/src/StringBuilder.c.ri
@@ -1,5 +1,5 @@
-// Copyright (C) 2023-present Jose Mendoza - All rights reserved. Use of this 
-// source code is governed by an MIT license that can be found in the LICENSE 
+// Copyright (C) 2023-present Jose Mendoza - All rights reserved. Use of this
+// source code is governed by an MIT license that can be found in the LICENSE
 // file.
 
 import c/libc;
@@ -65,7 +65,7 @@ pub struct StringBuilder < Stringable {
         self.write_byte('\n');
     }
 
-    pub func write_join(mut self, ss: []string, sep: string := "") {
+    pub func write_join(mut self, ss: [:]string, sep: string := "") {
         if ss.len == 1 {
             self.write_string(ss[0]);
         } else {
diff --git a/lib/rivet/src/ast/Env.ri b/lib/rivet/src/ast/Env.ri
index 6703a0d09..1123c6e8e 100644
--- a/lib/rivet/src/ast/Env.ri
+++ b/lib/rivet/src/ast/Env.ri
@@ -5,7 +5,6 @@
 import std/sys;
 import std/fs.Path;
 
-import ../token;
 import ../prefs;
 import ../report;
 import ../utils;
diff --git a/lib/rivet/src/builder/mod.ri b/lib/rivet/src/builder/mod.ri
index 5b6753f4d..155348dc2 100644
--- a/lib/rivet/src/builder/mod.ri
+++ b/lib/rivet/src/builder/mod.ri
@@ -238,12 +238,12 @@ pub struct Builder {
                     "/"
                 );
                 full_name = if "src" in names {
-                    src_idx := utils.index_of(names, "src");
+                    src_idx := utils.index_of(names[:], "src");
                     utils.join(names[:src_idx], ".").concat(
                         ".", utils.join(names[src_idx + 1:], ".")
                     )
                 } else {
-                    utils.join(names, ".")
+                    utils.join(names[:], ".")
                 };
             }
             if found {
diff --git a/lib/rivet/src/checker/call_expr.ri b/lib/rivet/src/checker/call_expr.ri
index 17cc1b073..92735488c 100644
--- a/lib/rivet/src/checker/call_expr.ri
+++ b/lib/rivet/src/checker/call_expr.ri
@@ -1,5 +1,5 @@
-// Copyright (C) 2023-present Jose Mendoza - All rights reserved. Use of this 
-// source code is governed by an MIT license that can be found in the LICENSE 
+// Copyright (C) 2023-present Jose Mendoza - All rights reserved. Use of this
+// source code is governed by an MIT license that can be found in the LICENSE
 // file.
 
 import ../ast;
@@ -422,7 +422,7 @@ extend Checker {
         // check default expressions
         if func_.has_named_args {
             args_len := call_expr.pure_args_count();
-            mut args := call_expr.args[:args_len];
+            mut args := call_expr.args[:args_len].to_dynamic_array();
             mut i: uint := args_len;
             while i < func_args_len : i += 1 {
                 arg := func_.args[i];
diff --git a/lib/rivet/src/checker/exprs.ri b/lib/rivet/src/checker/exprs.ri
index 0179276e8..e6ec6becb 100644
--- a/lib/rivet/src/checker/exprs.ri
+++ b/lib/rivet/src/checker/exprs.ri
@@ -276,8 +276,8 @@ extend Checker {
                     }
                     self.inside_unsafe_block = false;
                 }
-                block.defer_stmts = self.defer_stmts[self.defer_stmts_start:];
-                self.defer_stmts = self.defer_stmts[:self.defer_stmts_start];
+                block.defer_stmts = self.defer_stmts[self.defer_stmts_start:].to_dynamic_array();
+                self.defer_stmts = self.defer_stmts[:self.defer_stmts_start].to_dynamic_array();
                 block.type
             },
             .Unary(mut unary) -> self.check_unary(unary),
diff --git a/lib/rivet/src/checker/match_expr.ri b/lib/rivet/src/checker/match_expr.ri
index 8c598f505..10cce1eb0 100644
--- a/lib/rivet/src/checker/match_expr.ri
+++ b/lib/rivet/src/checker/match_expr.ri
@@ -1,5 +1,5 @@
-// Copyright (C) 2023-present Jose Mendoza - All rights reserved. Use of this 
-// source code is governed by an MIT license that can be found in the LICENSE 
+// Copyright (C) 2023-present Jose Mendoza - All rights reserved. Use of this
+// source code is governed by an MIT license that can be found in the LICENSE
 // file.
 
 import ../ast;
@@ -198,7 +198,7 @@ extend Checker {
         if unhandled.len > 0 {
             mut err_details := "add `match` branches for: ";
             if unhandled.len < MATCH_EXHAUSTIVE_CUTOFF_LIMIT {
-                err_details = err_details.concat(utils.join(unhandled, ", "));
+                err_details = err_details.concat(utils.join(unhandled[:], ", "));
             } else {
                 err_details = err_details.concat(
                     utils.join(unhandled[:MATCH_EXHAUSTIVE_CUTOFF_LIMIT], ", ")
diff --git a/lib/rivet/src/depgraph/mod.ri b/lib/rivet/src/depgraph/mod.ri
index d65939325..6216948bb 100644
--- a/lib/rivet/src/depgraph/mod.ri
+++ b/lib/rivet/src/depgraph/mod.ri
@@ -1,5 +1,5 @@
-// Copyright (C) 2023-present Jose Mendoza - All rights reserved. Use of this 
-// source code is governed by an MIT license that can be found in the LICENSE 
+// Copyright (C) 2023-present Jose Mendoza - All rights reserved. Use of this
+// source code is governed by an MIT license that can be found in the LICENSE
 // file.
 
 import std/strings;
@@ -89,7 +89,7 @@ pub struct DepGraph {
             }
             (seen, cycle_names) = nn.is_part_of_cycle(k.key, cycle_names);
             if seen {
-                out.writeln_fmt(" * `{}`", utils.join(cycle_names, "` -> `"));
+                out.writeln_fmt(" * `{}`", utils.join(cycle_names[:], "` -> `"));
                 nn.is_cycle = maps.MapStringBool();
             }
         }
diff --git a/lib/rivet/src/prefs/mod.ri b/lib/rivet/src/prefs/mod.ri
index 9f3da1de8..5b4c7eeb6 100644
--- a/lib/rivet/src/prefs/mod.ri
+++ b/lib/rivet/src/prefs/mod.ri
@@ -1,5 +1,5 @@
-// Copyright (C) 2023-present Jose Mendoza - All rights reserved. Use of this 
-// source code is governed by an MIT license that can be found in the LICENSE 
+// Copyright (C) 2023-present Jose Mendoza - All rights reserved. Use of this
+// source code is governed by an MIT license that can be found in the LICENSE
 // file.
 
 import std/env;
@@ -82,7 +82,7 @@ pub struct Prefs {
     pub mut run_output: bool;
     pub mut run_output_args: []string;
 
-    pub func from_args(args: []string, is_test: bool, run_output: bool, is_check: bool) -> !Self {
+    pub func from_args(args: [:]string, is_test: bool, run_output: bool, is_check: bool) -> !Self {
         mut prefs := Prefs(is_test: is_test, run_output: run_output, check: is_check);
         mut fp := flag.FlagParser.new(args);
         fp.set_application_name(if is_test {
diff --git a/lib/rivet/src/tokenizer/mod.ri b/lib/rivet/src/tokenizer/mod.ri
index b111f1796..869395f50 100644
--- a/lib/rivet/src/tokenizer/mod.ri
+++ b/lib/rivet/src/tokenizer/mod.ri
@@ -252,7 +252,7 @@ pub struct Tokenizer {
                 s.substr(end_idx)
             });
         }
-        return utils.join(ss, "");
+        return utils.join(ss[:], "");
     }
 
     #[inline]
@@ -298,7 +298,7 @@ func decode_o_escapes(s: string, start: uint, escapes_pos: []uint) -> string {
             s.substr(end_idx)
         });
     }
-    return utils.join(ss, "");
+    return utils.join(ss[:], "");
 }
 
 func decode_u_escape_single(str: string, idx: uint) -> (uint, string) {
@@ -316,7 +316,7 @@ func decode_unicode_escaped_rune(str: string) -> string {
         mut ss := []string(cap: 2);
         ss.push(segment);
         ss.push(str.substr(end_idx));
-        utils.join(ss, "")
+        utils.join(ss[:], "")
     };
 }
 
diff --git a/lib/rivet/src/tokenizer/next.ri b/lib/rivet/src/tokenizer/next.ri
index b3271acd2..e566e81d2 100644
--- a/lib/rivet/src/tokenizer/next.ri
+++ b/lib/rivet/src/tokenizer/next.ri
@@ -766,7 +766,7 @@ extend Tokenizer {
                 if segment_idx < lit.len {
                     str_segments.push(lit.substr(segment_idx));
                 }
-                lit = utils.join(str_segments, "");
+                lit = utils.join(str_segments[:], "");
             }
             if n_cr_chars > 0 {
                 lit = lit.replace("\r", "");
diff --git a/lib/rivet/src/utils/array.ri b/lib/rivet/src/utils/array.ri
index 82b92d62f..315fcff28 100644
--- a/lib/rivet/src/utils/array.ri
+++ b/lib/rivet/src/utils/array.ri
@@ -1,21 +1,21 @@
-// Copyright (C) 2023-present Jose Mendoza - All rights reserved. Use of this 
-// source code is governed by an MIT license that can be found in the LICENSE 
+// Copyright (C) 2023-present Jose Mendoza - All rights reserved. Use of this
+// source code is governed by an MIT license that can be found in the LICENSE
 // file.
 
 import std/strings;
 
-pub func join(vec: []string, s: string) -> string {
-    return if vec.is_empty() {
+pub func join(slice: [:]string, s: string) -> string {
+    return if slice.is_empty() {
         ""
     } else {
         mut sb := strings.Builder.new();
-        sb.write_join(vec, s);
+        sb.write_join(slice, s);
         sb.to_string()
     };
 }
 
-pub func index_of(vec: []string, value: string) -> uint {
-    for i, val in vec {
+pub func index_of(slice: [:]string, value: string) -> uint {
+    for i, val in slice {
         if val == value {
             return i;
         }
diff --git a/lib/rivet/src/utils/file.ri b/lib/rivet/src/utils/file.ri
index 6b90664fe..1302df30d 100644
--- a/lib/rivet/src/utils/file.ri
+++ b/lib/rivet/src/utils/file.ri
@@ -1,5 +1,5 @@
-// Copyright (C) 2023-present Jose Mendoza - All rights reserved. Use of this 
-// source code is governed by an MIT license that can be found in the LICENSE 
+// Copyright (C) 2023-present Jose Mendoza - All rights reserved. Use of this
+// source code is governed by an MIT license that can be found in the LICENSE
 // file.
 
 import std/env;
@@ -57,7 +57,7 @@ struct SourceCache {
 	  };
    }
 
-   pub func find_lines_between(mut self, path_: string, line: uint, end_line: uint) -> ?[]string {
+   pub func find_lines_between(mut self, path_: string, line: uint, end_line: uint) -> ?[:]string {
 	  return if lines := self.find_lines(path_) {
 		if lines.len > 0 && lines.len >= end_line {
 			lines[line:end_line]
diff --git a/lib/std/src/flag/mod.ri b/lib/std/src/flag/mod.ri
index 14a936fc4..23069cfc6 100644
--- a/lib/std/src/flag/mod.ri
+++ b/lib/std/src/flag/mod.ri
@@ -1,5 +1,5 @@
-// Copyright (C) 2023-present Jose Mendoza - All rights reserved. Use of this 
-// source code is governed by an MIT license that can be found in the LICENSE 
+// Copyright (C) 2023-present Jose Mendoza - All rights reserved. Use of this
+// source code is governed by an MIT license that can be found in the LICENSE
 // file.
 
 import ../traits;
@@ -42,7 +42,7 @@ pub struct Flag < traits.Stringable {
 #[boxed]
 pub struct FlagParser {
     /// The original arguments to be parsed.
-    original_args: []string;
+    original_args: [:]string;
     /// The index of a `--`, `none` if there is not any.
     idx_dashdash: ?uint;
     /// All options after `--` are ignored, and will be passed to the application unmodified.
@@ -71,19 +71,18 @@ pub struct FlagParser {
     mut footers: []string;
 
     /// Create a new flag parser for the given args.
-    pub func new(args: []string) -> Self {
-        original_args := args.clone();
-        mut all_before_dashdash := args.clone();
+    pub func new(args: [:]string) -> Self {
+        mut all_before_dashdash := args.to_dynamic_array();
         mut all_after_dashdash := []string();
         idx_dashdash := index_of(args, "--");
         if v := idx_dashdash {
             all_before_dashdash.trim(v);
-            if v < original_args.len {
-                all_after_dashdash = original_args[v + 1:];
+            if v < args.len {
+                all_after_dashdash = args[v + 1:].to_dynamic_array();
             }
         }
         return Self(
-            original_args: original_args,
+            original_args: args,
             idx_dashdash: idx_dashdash,
             all_after_dashdash: all_after_dashdash,
             args: all_before_dashdash,
@@ -487,8 +486,8 @@ pub struct FlagParser {
     }
 }
 
-pub func index_of(vec: []string, value: string) -> ?uint {
-    for i, val in vec {
+pub func index_of(slice: [:]string, value: string) -> ?uint {
+    for i, val in slice {
         if val == value {
             return i;
         }
diff --git a/rivetc/src/codegen/__init__.py b/rivetc/src/codegen/__init__.py
index e7c87b016..c4478a7b0 100644
--- a/rivetc/src/codegen/__init__.py
+++ b/rivetc/src/codegen/__init__.py
@@ -1630,18 +1630,20 @@ def gen_expr(self, expr, custom_tmp = None):
                     else:
                         end = None
                 tmp = self.cur_func.local_name()
-                if s.kind == TypeKind.DynArray:
+                if s.kind in (TypeKind.DynArray, TypeKind.Slice):
                     if end == None:
+                        method_name = "_R4core5Slice10slice_fromM" if s.kind==TypeKind.Slice else "_R4core8DynArray10slice_fromM"
                         inst = ir.Inst(
                             ir.InstKind.Call, [
-                                ir.Name("_R4core8DynArray10slice_fromM"), left,
+                                ir.Name(method_name), left,
                                 start
                             ]
                         )
                     else:
+                        method_name = "_R4core5Slice5sliceM" if s.kind==TypeKind.Slice else "_R4core8DynArray5sliceM"
                         inst = ir.Inst(
                             ir.InstKind.Call, [
-                                ir.Name("_R4core8DynArray5sliceM"), left, start,
+                                ir.Name(method_name), left, start,
                                 end
                             ]
                         )
diff --git a/rivetc/src/type.py b/rivetc/src/type.py
index 37542327b..55ab50d13 100644
--- a/rivetc/src/type.py
+++ b/rivetc/src/type.py
@@ -167,7 +167,7 @@ def qualstr(self):
         return f"[:]{self.typ.qualstr()}"
 
     def __eq__(self, other):
-        if not isinstance(other, DynArray):
+        if not isinstance(other, Slice):
             return False
         return self.typ == other.typ and self.is_mut == other.is_mut