diff --git a/Cargo.lock b/Cargo.lock
index 8983f9e..7e60c0c 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1,6 +1,6 @@
 [root]
 name = "tantivy-cli"
-version = "0.3.0"
+version = "0.4.0-alpha"
 dependencies = [
  "ansi_term 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "bincode 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -13,9 +13,11 @@ dependencies = [
  "log 0.3.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "mount 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "persistent 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-serialize 0.3.24 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_derive 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_json 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "staticfile 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "tantivy 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "tantivy 0.4.0-alpha",
  "time 0.1.36 (registry+https://github.com/rust-lang/crates.io-index)",
  "urlencoded 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "version 2.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -86,13 +88,12 @@ dependencies = [
 
 [[package]]
 name = "bincode"
-version = "0.5.9"
+version = "0.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "byteorder 0.5.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "byteorder 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "num-traits 0.1.37 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-serialize 0.3.24 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde 0.7.15 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 0.9.15 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -208,6 +209,11 @@ name = "dtoa"
 version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "dtoa"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "either"
 version = "1.1.0"
@@ -349,6 +355,11 @@ name = "itoa"
 version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "itoa"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "kernel32-sys"
 version = "0.2.2"
@@ -577,6 +588,11 @@ dependencies = [
  "getopts 0.2.14 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "quote"
+version = "0.3.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "rand"
 version = "0.3.15"
@@ -657,13 +673,37 @@ dependencies = [
 
 [[package]]
 name = "serde"
-version = "0.7.15"
+version = "0.8.23"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "serde"
-version = "0.8.23"
+version = "0.9.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "serde"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "serde_derive"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "quote 0.3.15 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_derive_internals 0.15.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 0.11.11 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "serde_derive_internals"
+version = "0.15.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "syn 0.11.11 (registry+https://github.com/rust-lang/crates.io-index)",
+ "synom 0.11.3 (registry+https://github.com/rust-lang/crates.io-index)",
+]
 
 [[package]]
 name = "serde_json"
@@ -676,6 +716,17 @@ dependencies = [
  "serde 0.8.23 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "serde_json"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "dtoa 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "itoa 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "num-traits 0.1.37 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "skeptic"
 version = "0.6.1"
@@ -712,12 +763,29 @@ version = "0.6.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
-name = "tantivy"
-version = "0.3.1"
+name = "syn"
+version = "0.11.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "quote 0.3.15 (registry+https://github.com/rust-lang/crates.io-index)",
+ "synom 0.11.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "unicode-xid 0.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "synom"
+version = "0.11.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "unicode-xid 0.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "tantivy"
+version = "0.4.0-alpha"
 dependencies = [
  "atomicwrites 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "bincode 0.5.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "bincode 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "bit-set 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "byteorder 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "chan 0.1.19 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -735,11 +803,13 @@ dependencies = [
  "memmap 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "num_cpus 1.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "regex 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-serialize 0.3.24 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_derive 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_json 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "tempdir 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "tempfile 2.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "time 0.1.36 (registry+https://github.com/rust-lang/crates.io-index)",
- "uuid 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "uuid 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "version 2.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -874,6 +944,11 @@ name = "unicode-width"
 version = "0.1.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "unicode-xid"
+version = "0.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "unreachable"
 version = "0.1.1"
@@ -922,11 +997,11 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "uuid"
-version = "0.4.0"
+version = "0.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "rand 0.3.15 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-serialize 0.3.24 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -963,7 +1038,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum atomicwrites 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)" = "c4328d3fa4af4aedc582587976a0f74decc73f90ea7cae3d757c0535f983d16f"
 "checksum atty 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "d912da0db7fa85514874458ca3651fe2cddace8d0b0505571dbdcd41ab490159"
 "checksum bincode 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)" = "60f89d68caf4f2e8a94efd192a2b8393869e72336dea4e0fe077cc6eb5f2057e"
-"checksum bincode 0.5.9 (registry+https://github.com/rust-lang/crates.io-index)" = "aa413a0580cf7d54f1938c13462fd32cff9099338bf161e15870cb05021df745"
+"checksum bincode 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "bea6e613eeed56804328309c4227e61a0326a8810e1392d91faeb2124b77f43e"
 "checksum bit-set 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d9bf6104718e80d7b26a68fdbacff3481cfc05df670821affc7e9cbc1884400c"
 "checksum bit-vec 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)" = "5b97c2c8e8bbb4251754f559df8af22fb264853c7d009084a576cdf12565089d"
 "checksum bitflags 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "8dead7461c1127cf637931a1e50934eb6eee8bff2f74433ac7909e9afcee04a3"
@@ -980,6 +1055,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum cookie 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)" = "0e3d6405328b6edb412158b3b7710e2634e23f3614b9bb1c412df7952489a626"
 "checksum crossbeam 0.2.10 (registry+https://github.com/rust-lang/crates.io-index)" = "0c5ea215664ca264da8a9d9c3be80d2eaf30923c259d03e870388eb927508f97"
 "checksum dtoa 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "0dd841b58510c9618291ffa448da2e4e0f699d984d436122372f446dae62263d"
+"checksum dtoa 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)" = "80c8b71fd71146990a9742fc06dcbbde19161a267e0ad4e572c35162f4578c90"
 "checksum either 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "18785c1ba806c258137c937e44ada9ee7e69a37e3c72077542cd2f069d78562a"
 "checksum env_logger 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)" = "15abd780e45b3ea4f76b4e9a26ff4843258dd8a3eed2775a0e7368c2e7936c2f"
 "checksum error 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)" = "a6e606f14042bb87cc02ef6a14db6c90ab92ed6f62d87e69377bc759fd7987cc"
@@ -996,6 +1072,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum iron 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "9fb1b2d809f84bf347e472d5758762b5c804e0c622970235f156d82673e4d334"
 "checksum itertools 0.5.10 (registry+https://github.com/rust-lang/crates.io-index)" = "4833d6978da405305126af4ac88569b5d71ff758581ce5a987dbfa3755f694fc"
 "checksum itoa 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "ae3088ea4baeceb0284ee9eea42f591226e6beaecf65373e41b38d95a1b8e7a1"
+"checksum itoa 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "eb2f404fbc66fd9aac13e998248505e7ecb2ad8e44ab6388684c5fb11c6c251c"
 "checksum kernel32-sys 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "7507624b29483431c0ba2d82aece8ca6cdba9382bff4ddd0f7490560c056098d"
 "checksum language-tags 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "a91d884b6667cd606bb5a69aa0c99ba811a115fc68915e7056ec08a46e93199a"
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@@ -1024,6 +1101,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum persistent 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "0c0aea7e6e026f9090c56aa7cda9d4ad6f182c717f0640cb03beace1f75a43d2"
 "checksum plugin 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)" = "1a6a0dc3910bc8db877ffed8e457763b317cf880df4ae19109b9f77d277cf6e0"
 "checksum pulldown-cmark 0.0.3 (registry+https://github.com/rust-lang/crates.io-index)" = "8361e81576d2e02643b04950e487ec172b687180da65c731c03cf336784e6c07"
+"checksum quote 0.3.15 (registry+https://github.com/rust-lang/crates.io-index)" = "7a6e920b65c65f10b2ae65c831a81a073a89edd28c7cce89475bff467ab4167a"
 "checksum rand 0.3.15 (registry+https://github.com/rust-lang/crates.io-index)" = "022e0636ec2519ddae48154b028864bdce4eaf7d35226ab8e65c611be97b189d"
 "checksum redox_syscall 0.1.17 (registry+https://github.com/rust-lang/crates.io-index)" = "29dbdfd4b9df8ab31dec47c6087b7b13cbf4a776f335e4de8efba8288dda075b"
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@@ -1035,14 +1113,19 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum semver 0.1.20 (registry+https://github.com/rust-lang/crates.io-index)" = "d4f410fedcf71af0345d7607d246e7ad15faaadd49d240ee3b24e5dc21a820ac"
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@@ -1060,13 +1143,14 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum unicode-normalization 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)" = "e28fa37426fceeb5cf8f41ee273faa7c82c47dc8fba5853402841e665fcd86ff"
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-"checksum uuid 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "7cfec50b0842181ba6e713151b72f4ec84a6a7e2c9c8a8a3ffc37bb1cd16b231"
+"checksum uuid 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)" = "b5d0f5103675a280a926ec2f9b7bcc2ef49367df54e8c570c3311fec919f9a8b"
 "checksum vec_map 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "f8cdc8b93bd0198ed872357fb2e667f7125646b1762f16d60b2c96350d361897"
 "checksum version 2.0.1 (registry+https://github.com/rust-lang/crates.io-index)" = "4c941215489baf638156fcc85c59a45444709a7ac2093b9b22b45e3cfe80fe26"
 "checksum void 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "6a02e4885ed3bc0f2de90ea6dd45ebcbb66dacffe03547fadbb0eeae2770887d"
diff --git a/Cargo.toml b/Cargo.toml
index 1ab235a..40925be 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "tantivy-cli"
-version = "0.3.0"
+version = "0.4.0-alpha"
 authors = ["Paul Masurel <paul.masurel@gmail.com>"]
 
 description = """Command line interface for Tantivy, a search engine library."""
@@ -16,7 +16,9 @@ license = "MIT"
 time = "0.1"
 iron = "0.4"
 staticfile = "0.3"
-rustc-serialize = "0.3"
+serde = "1.0"
+serde_derive = "1.0"
+serde_json = "1.0"
 persistent="0.2"
 clap = "2"
 ansi_term = "0.8"
@@ -29,7 +31,8 @@ log = "0.3"
 futures = "0.1"
 env_logger = "0.3"
 version = "2"
-tantivy = "0.3.1"
+#tantivy = "0.3.1"
+tantivy = { path="../tantivy", branch="master" }
 
 [[bin]]
 name = "tantivy"
diff --git a/README.md b/README.md
index ae74265..0579b86 100644
--- a/README.md
+++ b/README.md
@@ -40,7 +40,7 @@ We will now initialize the index and create its schema.
 The [schema](https://tantivy-search.github.io/tantivy/tantivy/schema/index.html) defines
 the list of your fields, and for each field:
 - its name 
-- its type, currently `u32` or `str`
+- its type, currently `u64`, `i64` or `str`
 - how it should be indexed.
 
 You can find more information about the latter on 
diff --git a/src/commands/bench.rs b/src/commands/bench.rs
index 921700b..4f348d4 100644
--- a/src/commands/bench.rs
+++ b/src/commands/bench.rs
@@ -29,8 +29,7 @@ fn extract_search_fields(schema: &Schema) -> Vec<Field> {
           .filter(|&(_, field_entry)| {
               field_entry.is_indexed()
           })
-          .map(|(field_id, _)| field_id as u8)
-          .map(Field)
+          .map(|(field_id, _)| Field(field_id as u32))
           .collect()
 }
 
diff --git a/src/commands/new.rs b/src/commands/new.rs
index 8c68882..7f84183 100644
--- a/src/commands/new.rs
+++ b/src/commands/new.rs
@@ -9,7 +9,7 @@ use ansi_term::Style;
 use ansi_term::Colour::{Red, Blue, Green};
 use std::io::Write;
 use std::ascii::AsciiExt;
-use rustc_serialize::json;
+use serde_json;
 
 
 pub fn run_new_cli(matches: &ArgMatches) -> Result<(), String> {
@@ -104,18 +104,18 @@ fn ask_add_field_text(field_name: &str, schema_builder: &mut SchemaBuilder) {
 }
 
 
-fn ask_add_field_u32(field_name: &str, schema_builder: &mut SchemaBuilder) {
-    let mut u32_options = U32Options::default();
+fn ask_add_field_u64(field_name: &str, schema_builder: &mut SchemaBuilder) {
+    let mut u64_options = IntOptions::default();
     if prompt_yn("Should the field be stored") {
-        u32_options = u32_options.set_stored();
+        u64_options = u64_options.set_stored();
     }
     if prompt_yn("Should the field be fast") {
-        u32_options = u32_options.set_fast();
+        u64_options = u64_options.set_fast();
     }
     if prompt_yn("Should the field be indexed") {
-        u32_options = u32_options.set_indexed();
+        u64_options = u64_options.set_indexed();
     }
-    schema_builder.add_u32_field(field_name, u32_options);
+    schema_builder.add_u64_field(field_name, u64_options);
 }
 
 fn ask_add_field(schema_builder: &mut SchemaBuilder) {
@@ -126,7 +126,7 @@ fn ask_add_field(schema_builder: &mut SchemaBuilder) {
         ask_add_field_text(&field_name, schema_builder);
     }
     else {
-        ask_add_field_u32(&field_name, schema_builder);        
+        ask_add_field_u64(&field_name, schema_builder);        
     }
 }
 
@@ -141,7 +141,7 @@ fn run_new(directory: PathBuf) -> tantivy::Result<()> {
         }
     }
     let schema = schema_builder.build();
-    let schema_json = format!("{}", json::as_pretty_json(&schema));
+    let schema_json = format!("{}", serde_json::to_string_pretty(&schema).unwrap());
     println!("\n{}\n", Style::new().fg(Green).paint(schema_json));
     Index::create(&directory, schema)?;
     Ok(())
diff --git a/src/commands/search.rs b/src/commands/search.rs
index 4085fcb..286767d 100644
--- a/src/commands/search.rs
+++ b/src/commands/search.rs
@@ -1,5 +1,4 @@
 use clap::ArgMatches;
-use rustc_serialize::json::as_json;
 use std::convert::From;
 use std::path::Path;
 use std::path::PathBuf;
@@ -7,6 +6,7 @@ use tantivy;
 use tantivy::Index;
 use tantivy::query::QueryParser;
 use tantivy::schema::Field;
+use serde_json;
 use tantivy::schema::FieldType;
 
 pub fn run_search_cli(matches: &ArgMatches) -> Result<(), String> {
@@ -28,11 +28,11 @@ fn run_search(directory: &Path, query: &str) -> tantivy::Result<()> {
                     FieldType::Str(ref text_field_options) => {
                         text_field_options.get_indexing_options().is_indexed()
                     },
-                    FieldType::U32(_) => false
+                    _ => false
                 }
             }
         )
-        .map(|(i, _)| Field(i as u8))
+        .map(|(i, _)| Field(i as u32))
         .collect();
     let query_parser = QueryParser::new(schema.clone(), default_fields);
     let query = query_parser.parse_query(query)?;
@@ -45,7 +45,7 @@ fn run_search(directory: &Path, query: &str) -> tantivy::Result<()> {
             let doc_id = scorer.doc();
             let doc = segment_reader.doc(doc_id)?;
             let named_doc = schema.to_named_doc(&doc);
-            println!("{}", as_json(&named_doc));
+            println!("{}", serde_json::to_string(&named_doc).unwrap());
         }
     }
     Ok(())
diff --git a/src/commands/serve.rs b/src/commands/serve.rs
index a781684..d9162ff 100644
--- a/src/commands/serve.rs
+++ b/src/commands/serve.rs
@@ -18,10 +18,10 @@ use clap::ArgMatches;
 use iron::mime::Mime;
 use iron::prelude::*;
 use iron::status;
+use serde_json;
 use iron::typemap::Key;
 use mount::Mount;
 use persistent::Read;
-use rustc_serialize::json::as_pretty_json;
 use std::convert::From;
 use std::error::Error;
 use std::fmt::{self, Debug};
@@ -51,7 +51,7 @@ pub fn run_serve_cli(matches: &ArgMatches) -> Result<(), String> {
 }
 
 
-#[derive(RustcEncodable)]
+#[derive(Serialize)]
 struct Serp {
     q: String,
     num_hits: usize,
@@ -59,7 +59,7 @@ struct Serp {
     timings: TimerTree,
 }
 
-#[derive(RustcEncodable)]
+#[derive(Serialize)]
 struct Hit {
     doc: NamedFieldDocument,
 }
@@ -85,11 +85,11 @@ impl IndexServer {
                         FieldType::Str(ref text_field_options) => {
                             text_field_options.get_indexing_options().is_indexed()
                         },
-                        FieldType::U32(_) => false
+                        _ => false
                     }
                 }
             )
-            .map(|(i, _)| Field(i as u8))
+            .map(|(i, _)| Field(i as u32))
             .collect();
         let query_parser = QueryParser::new(schema.clone(), default_fields);
         IndexServer {
@@ -167,7 +167,7 @@ fn search(req: &mut Request) -> IronResult<Response> {
                 .get("q")
                 .ok_or_else(|| IronError::new(StringError(String::from("Parameter q is missing from the query")), status::BadRequest)))[0].clone();
             let serp = index_server.search(query, num_hits).unwrap();
-            let resp_json = as_pretty_json(&serp).indent(4);
+            let resp_json = serde_json::to_string_pretty(&serp).unwrap();
             let content_type = "application/json".parse::<Mime>().unwrap();
             Ok(Response::with((content_type, status::Ok, format!("{}", resp_json))))
         })
diff --git a/src/main.rs b/src/main.rs
index 9c20f7b..6b84ba8 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -2,7 +2,7 @@
 extern crate clap;
 #[macro_use]
 extern crate version;
-extern crate rustc_serialize;
+extern crate serde_json;
 #[macro_use]
 extern crate log;
 extern crate env_logger;
@@ -19,6 +19,9 @@ extern crate mount;
 extern crate bincode;
 extern crate byteorder;
 
+#[macro_use]
+extern crate serde_derive;
+
 use clap::{AppSettings, Arg, App, SubCommand};
 mod commands;
 use self::commands::*;