diff --git a/.gitattributes b/.gitattributes
new file mode 100644
index 0000000..f47c63a
--- /dev/null
+++ b/.gitattributes
@@ -0,0 +1,2 @@
+# 强制所有文件使用 LF 换行符
+* text=auto eol=lf
diff --git a/.gitignore b/.gitignore
index ea8c4bf..70bfe5d 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,2 @@
 /target
+/fixtures
diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index dee6400..f4d2fd9 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -55,7 +55,7 @@ repos:
       - id: cargo-test
         name: cargo test
         description: unit test for the project
-        entry: bash -c 'cargo nextest run --all-features'
+        entry: bash -c 'cargo nextest run --all-features --no-tests="warn"'
         language: rust
         files: \.rs$
         pass_filenames: false
diff --git a/Cargo.lock b/Cargo.lock
index be35886..ead00e4 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1,7 +1,375 @@
 # This file is automatically @generated by Cargo.
 # It is not intended for manual editing.
-version = 3
+version = 4
 
 [[package]]
-name = "rust-template"
+name = "anstream"
+version = "0.6.21"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "43d5b281e737544384e969a5ccad3f1cdd24b48086a0fc1b2a5262a26b8f4f4a"
+dependencies = [
+ "anstyle",
+ "anstyle-parse",
+ "anstyle-query",
+ "anstyle-wincon",
+ "colorchoice",
+ "is_terminal_polyfill",
+ "utf8parse",
+]
+
+[[package]]
+name = "anstyle"
+version = "1.0.13"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5192cca8006f1fd4f7237516f40fa183bb07f8fbdfedaa0036de5ea9b0b45e78"
+
+[[package]]
+name = "anstyle-parse"
+version = "0.2.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4e7644824f0aa2c7b9384579234ef10eb7efb6a0deb83f9630a49594dd9c15c2"
+dependencies = [
+ "utf8parse",
+]
+
+[[package]]
+name = "anstyle-query"
+version = "1.1.5"
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+dependencies = [
+ "windows-sys",
+]
+
+[[package]]
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+dependencies = [
+ "anstyle",
+ "once_cell_polyfill",
+ "windows-sys",
+]
+
+[[package]]
+name = "anyhow"
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+source = "registry+https://github.com/rust-lang/crates.io-index"
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+
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+dependencies = [
+ "clap_builder",
+ "clap_derive",
+]
+
+[[package]]
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+source = "registry+https://github.com/rust-lang/crates.io-index"
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+dependencies = [
+ "anstream",
+ "anstyle",
+ "clap_lex",
+ "strsim",
+]
+
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+ "heck",
+ "proc-macro2",
+ "quote",
+ "syn",
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+
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+
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+
+[[package]]
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+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "52cd9d68cf7efc6ddfaaee42e7288d3a99d613d4b50f76ce9827ae0c6e14f938"
+dependencies = [
+ "csv-core",
+ "itoa",
+ "ryu",
+ "serde_core",
+]
+
+[[package]]
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+version = "0.1.13"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "704a3c26996a80471189265814dbc2c257598b96b8a7feae2d31ace646bb9782"
+dependencies = [
+ "memchr",
+]
+
+[[package]]
+name = "equivalent"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "877a4ace8713b0bcf2a4e7eec82529c029f1d0619886d18145fea96c3ffe5c0f"
+
+[[package]]
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+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "841d1cc9bed7f9236f321df977030373f4a4163ae1a7dbfe1a51a2c1a51d9100"
+
+[[package]]
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+checksum = "2304e00983f87ffb38b55b444b5e3b60a884b5d30c0fca7d82fe33449bbe55ea"
+
+[[package]]
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+checksum = "0ad4bb2b565bca0645f4d68c5c9af97fba094e9791da685bf83cb5f3ce74acf2"
+dependencies = [
+ "equivalent",
+ "hashbrown",
+]
+
+[[package]]
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+
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+
+[[package]]
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+checksum = "f52b00d39961fc5b2736ea853c9cc86238e165017a493d1d5c8eac6bdc4cc273"
+
+[[package]]
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+version = "1.70.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "384b8ab6d37215f3c5301a95a4accb5d64aa607f1fcb26a11b5303878451b4fe"
+
+[[package]]
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+checksum = "5ee95bc4ef87b8d5ba32e8b7714ccc834865276eab0aed5c9958d00ec45f49e8"
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+ "unicode-ident",
+]
+
+[[package]]
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+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a338cc41d27e6cc6dce6cefc13a0729dfbb81c262b1f519331575dd80ef3067f"
+dependencies = [
+ "proc-macro2",
+]
+
+[[package]]
+name = "rcli"
 version = "0.1.0"
+dependencies = [
+ "anyhow",
+ "clap",
+ "csv",
+ "serde",
+ "serde_json",
+ "serde_yaml",
+ "toml",
+]
+
+[[package]]
+name = "ryu"
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+
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+dependencies = [
+ "serde_core",
+ "serde_derive",
+]
+
+[[package]]
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+ "serde_derive",
+]
+
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+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
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+ "itoa",
+ "memchr",
+ "ryu",
+ "serde",
+ "serde_core",
+]
+
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+ "serde_core",
+]
+
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+checksum = "6a8b1a1a2ebf674015cc02edccce75287f1a0130d394307b36743c2f5d504b47"
+dependencies = [
+ "indexmap",
+ "itoa",
+ "ryu",
+ "serde",
+ "unsafe-libyaml",
+]
+
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+checksum = "7da8b5736845d9f2fcb837ea5d9e2628564b3b043a70948a3f0b778838c5fb4f"
+
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+checksum = "390cc9a294ab71bdb1aa2e99d13be9c753cd2d7bd6560c77118597410c4d2e87"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "unicode-ident",
+]
+
+[[package]]
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+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f0dc8b1fb61449e27716ec0e1bdf0f6b8f3e8f6b05391e8497b8b6d7804ea6d8"
+dependencies = [
+ "indexmap",
+ "serde_core",
+ "serde_spanned",
+ "toml_datetime",
+ "toml_parser",
+ "toml_writer",
+ "winnow",
+]
+
+[[package]]
+name = "toml_datetime"
+version = "0.7.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f2cdb639ebbc97961c51720f858597f7f24c4fc295327923af55b74c3c724533"
+dependencies = [
+ "serde_core",
+]
+
+[[package]]
+name = "toml_parser"
+version = "1.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c0cbe268d35bdb4bb5a56a2de88d0ad0eb70af5384a99d648cd4b3d04039800e"
+dependencies = [
+ "winnow",
+]
+
+[[package]]
+name = "toml_writer"
+version = "1.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
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+
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+checksum = "9312f7c4f6ff9069b165498234ce8be658059c6728633667c526e27dc2cf1df5"
+
+[[package]]
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+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "673aac59facbab8a9007c7f6108d11f63b603f7cabff99fabf650fea5c32b861"
+
+[[package]]
+name = "utf8parse"
+version = "0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "06abde3611657adf66d383f00b093d7faecc7fa57071cce2578660c9f1010821"
+
+[[package]]
+name = "windows-link"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f0805222e57f7521d6a62e36fa9163bc891acd422f971defe97d64e70d0a4fe5"
+
+[[package]]
+name = "windows-sys"
+version = "0.61.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ae137229bcbd6cdf0f7b80a31df61766145077ddf49416a728b02cb3921ff3fc"
+dependencies = [
+ "windows-link",
+]
+
+[[package]]
+name = "winnow"
+version = "0.7.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5a5364e9d77fcdeeaa6062ced926ee3381faa2ee02d3eb83a5c27a8825540829"
diff --git a/Cargo.toml b/Cargo.toml
index 9c206ec..df4bc2d 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,8 +1,17 @@
 [package]
-name = "rust-template"
+name = "rcli"
 version = "0.1.0"
+authors = ["Bowen Hu <ry_grit@sina.com>"]
 edition = "2024"
+license = "MIT"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+anyhow = "1.0.100"
+clap = { version = "4.5.53", features = ["derive"] }
+csv = "1.4.0"
+serde = { version = "1.0.228", features = ["derive"] }
+serde_json = "1.0.145"
+serde_yaml = "0.9.34"
+toml = "0.9.8"
diff --git a/deny.toml b/deny.toml
index ba7d5ad..4821214 100644
--- a/deny.toml
+++ b/deny.toml
@@ -17,7 +17,7 @@
 # this list would mean the nix crate, as well as any of its exclusive
 # dependencies not shared by any other crates, would be ignored, as the target
 # list here is effectively saying which targets you are building for.
-targets = [
+# targets = [
   # The triple can be any string, but only the target triples built in to
   # rustc (as of 1.40) can be checked against actual config expressions
   #{ triple = "x86_64-unknown-linux-musl" },
@@ -25,26 +25,28 @@ targets = [
   # particular target. target_features are currently not validated against
   # the actual valid features supported by the target architecture.
   #{ triple = "wasm32-unknown-unknown", features = ["atomics"] },
-]
+# ]
 
 # This section is considered when running `cargo deny check advisories`
 # More documentation for the advisories section can be found here:
 # https://embarkstudios.github.io/cargo-deny/checks/advisories/cfg.html
+# https://github.com/EmbarkStudios/cargo-deny/pull/611
 [advisories]
+version = 2
 # The path where the advisory database is cloned/fetched into
 db-path = "~/.cargo/advisory-db"
 # The url(s) of the advisory databases to use
 db-urls = ["https://github.com/rustsec/advisory-db"]
 # The lint level for security vulnerabilities
-vulnerability = "deny"
+# vulnerability = "deny"
 # The lint level for unmaintained crates
-unmaintained = "warn"
+# unmaintained = "all"
 # The lint level for crates that have been yanked from their source registry
 yanked = "warn"
 # The lint level for crates with security notices. Note that as of
 # 2019-12-17 there are no security notice advisories in
 # https://github.com/rustsec/advisory-db
-notice = "warn"
+# notice = "deny"
 # A list of advisory IDs to ignore. Note that ignored advisories will still
 # output a note when they are encountered.
 ignore = [
@@ -63,9 +65,11 @@ ignore = [
 # This section is considered when running `cargo deny check licenses`
 # More documentation for the licenses section can be found here:
 # https://embarkstudios.github.io/cargo-deny/checks/licenses/cfg.html
+# https://github.com/EmbarkStudios/cargo-deny/pull/611
 [licenses]
+version = 2
 # The lint level for crates which do not have a detectable license
-unlicensed = "allow"
+# unlicensed = "allow"
 # List of explicitly allowed licenses
 # See https://spdx.org/licenses/ for list of possible licenses
 # [possible values: any SPDX 3.7 short identifier (+ optional exception)].
@@ -73,6 +77,7 @@ allow = [
   "MIT",
   "Apache-2.0",
   "Unicode-DFS-2016",
+  "Unicode-3.0",
   "MPL-2.0",
   "BSD-2-Clause",
   "BSD-3-Clause",
@@ -82,23 +87,23 @@ allow = [
 # List of explicitly disallowed licenses
 # See https://spdx.org/licenses/ for list of possible licenses
 # [possible values: any SPDX 3.7 short identifier (+ optional exception)].
-deny = [
+# deny = [
   #"Nokia",
-]
+# ]
 # Lint level for licenses considered copyleft
-copyleft = "warn"
+# copyleft = "deny"
 # Blanket approval or denial for OSI-approved or FSF Free/Libre licenses
 # * both - The license will be approved if it is both OSI-approved *AND* FSF
 # * either - The license will be approved if it is either OSI-approved *OR* FSF
 # * osi-only - The license will be approved if is OSI-approved *AND NOT* FSF
 # * fsf-only - The license will be approved if is FSF *AND NOT* OSI-approved
 # * neither - This predicate is ignored and the default lint level is used
-allow-osi-fsf-free = "neither"
+# allow-osi-fsf-free = "neither"
 # Lint level used when no other predicates are matched
 # 1. License isn't in the allow or deny lists
 # 2. License isn't copyleft
 # 3. License isn't OSI/FSF, or allow-osi-fsf-free = "neither"
-default = "deny"
+# default = "deny"
 # The confidence threshold for detecting a license from license text.
 # The higher the value, the more closely the license text must be to the
 # canonical license text of a valid SPDX license file.
diff --git a/src/lib.rs b/src/lib.rs
new file mode 100644
index 0000000..acb91b3
--- /dev/null
+++ b/src/lib.rs
@@ -0,0 +1,5 @@
+mod opts;
+mod process;
+
+pub use opts::{Opts, SubCommand};
+pub use process::process_csv;
diff --git a/src/main.rs b/src/main.rs
index e7a11a9..fcd582e 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,3 +1,15 @@
-fn main() {
-    println!("Hello, world!");
+use clap::Parser;
+use rcli::{Opts, SubCommand, process_csv};
+
+// rcli csv -i input.csv -o output.json --header -d ','
+
+fn main() -> anyhow::Result<()> {
+    let opts = Opts::parse();
+    match opts.cmd {
+        SubCommand::Csv(opts) => {
+            process_csv(&opts)?;
+        }
+    }
+
+    Ok(())
 }
diff --git a/src/opts.rs b/src/opts.rs
new file mode 100644
index 0000000..19a2b5f
--- /dev/null
+++ b/src/opts.rs
@@ -0,0 +1,88 @@
+use std::fmt;
+use std::{path::Path, str::FromStr};
+
+use clap::Parser;
+
+#[derive(Debug, Parser)]
+#[command(name = "rcli", version, author, about, long_about = None)]
+pub struct Opts {
+    #[command(subcommand)]
+    pub cmd: SubCommand,
+}
+
+#[derive(Debug, Parser)]
+pub enum SubCommand {
+    #[command(name = "csv", about = "Show CSV, or convert CSV to other formats")]
+    Csv(CsvOpts),
+}
+
+#[derive(Debug, Clone, Copy)]
+pub enum OutputFormat {
+    Json,
+    Yaml,
+    Toml,
+}
+
+impl From<&OutputFormat> for &'static str {
+    fn from(format: &OutputFormat) -> Self {
+        match format {
+            OutputFormat::Json => "json",
+            OutputFormat::Yaml => "yaml",
+            OutputFormat::Toml => "toml",
+        }
+    }
+}
+
+impl FromStr for OutputFormat {
+    type Err = anyhow::Error;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        match s.to_lowercase().as_str() {
+            "json" => Ok(OutputFormat::Json),
+            "yaml" => Ok(OutputFormat::Yaml),
+            "toml" => Ok(OutputFormat::Toml),
+            _ => Err(anyhow::anyhow!("Unsupported output format: {}", s)),
+        }
+    }
+}
+
+impl fmt::Display for OutputFormat {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let s: &str = self.into();
+        write!(f, "{}", s)
+    }
+}
+
+#[derive(Debug, Parser)]
+pub struct CsvOpts {
+    #[arg(short, long, value_parser = verify_input_file, help = "Input CSV file")]
+    pub input: String,
+
+    #[arg(short, long, help = "Output file")]
+    pub output: Option<String>,
+
+    #[arg(short, long, value_parser = parse_format, help = "Output format", default_value = "json")]
+    pub format: OutputFormat,
+
+    #[arg(
+        long,
+        help = "Indicates that the CSV file has a header row",
+        default_value_t = true
+    )]
+    pub header: bool,
+
+    #[arg(short, long, help = "Delimiter character", default_value_t = ',')]
+    pub delimiter: char,
+}
+
+fn verify_input_file(filename: &str) -> Result<String, String> {
+    if Path::new(filename).exists() {
+        Ok(filename.to_string())
+    } else {
+        Err(format!("Input file '{}' does not exist.", filename))
+    }
+}
+
+fn parse_format(format: &str) -> Result<OutputFormat, anyhow::Error> {
+    format.parse()
+}
diff --git a/src/process.rs b/src/process.rs
new file mode 100644
index 0000000..95ad676
--- /dev/null
+++ b/src/process.rs
@@ -0,0 +1,65 @@
+use std::{collections::HashMap, fs};
+
+use csv::Reader;
+use serde::{Deserialize, Serialize};
+use serde_json::Value;
+
+use crate::opts::{CsvOpts, OutputFormat};
+use anyhow::Ok;
+
+const TOML_ROOT_KEY: &str = "data";
+
+#[allow(dead_code)]
+#[derive(Debug, Serialize, Deserialize)]
+#[serde(rename_all = "PascalCase")]
+struct Player {
+    name: String,
+    position: String,
+    #[serde(rename = "DOB")]
+    dob: String,
+    nationality: String,
+    #[serde(rename = "Kit Number")]
+    kit: u8,
+}
+
+pub fn process_csv(opts: &CsvOpts) -> anyhow::Result<()> {
+    let output = match &opts.output {
+        Some(output) => output.clone(),
+        None => format!("output.{}", opts.format),
+    };
+    println!(
+        "Processing CSV file: {}, output file: {}",
+        opts.input, output
+    );
+    let mut reader_builder = Reader::from_path(&opts.input)?;
+    let mut parsed_records = Vec::with_capacity(128);
+    let headers = reader_builder.headers()?.clone();
+    for result in reader_builder.records() {
+        let record = result?;
+        let json_value = serde_json::Value::Object(
+            headers
+                .iter()
+                // zip() the headers and record into a JSON object
+                .zip(record.iter())
+                .map(|(k, v)| (k.to_string(), Value::String(v.to_string())))
+                .collect(),
+        );
+        parsed_records.push(json_value);
+    }
+
+    let content = match opts.format {
+        OutputFormat::Json => serde_json::to_string_pretty(&parsed_records)?,
+        OutputFormat::Yaml => serde_yaml::to_string(&parsed_records)?,
+        // TOML format requires the root element
+        OutputFormat::Toml => {
+            let mut map = HashMap::new();
+            map.insert(TOML_ROOT_KEY, &parsed_records);
+            toml::to_string(&map)?
+        }
+    };
+
+    fs::write(output, content)?;
+    println!("File converted successfully.");
+
+    Ok(())
+}