diff --git a/src/format.rs b/src/format.rs
index d05ef59..a05eced 100644
--- a/src/format.rs
+++ b/src/format.rs
@@ -48,12 +48,10 @@ pub trait Format {
     }
 
     /// Create a file at path with header and multiple records
-    fn create(
-        &self,
-        path: &std::path::Path,
-        rng: &mut rand::rngs::StdRng,
-        number: usize,
-    ) -> error::Result<()> {
+    fn create<P>(&self, path: P, rng: &mut rand::rngs::StdRng, number: usize) -> error::Result<()>
+    where
+        P: core::convert::AsRef<std::path::Path>,
+    {
         let mut output = std::io::BufWriter::new(std::fs::File::create(path)?);
 
         self.header(&mut output, rng)?;
diff --git a/src/format/fasta.rs b/src/format/fasta.rs
index e03c78c..381707c 100644
--- a/src/format/fasta.rs
+++ b/src/format/fasta.rs
@@ -1,4 +1,54 @@
 //! Fasta generation
+//!
+//! Usage:
+//! ```
+//! use biotest::Format as _; // import Format trait is required
+//!
+//! # fn main() -> Result<(), biotest::error::Error> {
+//! let mut rng = biotest::rand(); // Create a random generator with a fixed seed
+//!
+//! let mut output = Vec::new();
+//! let generator = biotest::Fasta::builder().build().unwrap();
+//!
+//! generator.record(&mut output, &mut rng)?; // Write one fasta record in output
+//! generator.records(&mut output, &mut rng, 5)?; // Write five fasta records in output
+//!
+//! generator.create("test.fasta", &mut rng, 5)?; // Write five fasta record in "test.fasta"
+//! # Ok(())
+//! # }
+//! ```
+//!
+//! Read generate follow this template
+//! ```ignore
+//! >{id_prefix}{id}{id_suffix} {comment_prefix}{comment}{comment_suffix}
+//! {sequence}
+//! ```
+//!
+//! Many think could be configurable with builder patern:
+//! ```
+//! use rand;
+//! use rand::SeedableRng;
+//! use biotest::Format;
+//!
+//! # fn main() -> Result<(), biotest::error::Error> {
+//! let mut rng = rand::rngs::StdRng::from_entropy(); // Create a random generator with a 'random' seed
+//!
+//! let generator = biotest::Fasta::builder()
+//!     .id(biotest::values::Alphabet::Lower) // Set alphabet use to generate sequence id
+//!     .id_len(10) // Set length of id
+//!     .id_prefix(b"prefix".to_vec()) // Set read id prefix
+//!     .id_suffix(b"suffix".to_vec()) // Set read id prefix
+//!     .comment(biotest::values::Alphabet::Upper) // Set alphabet use to generate sequence comment
+//!     .comment_len(0) // If comment length is set to 0 prefix and suffix isn't write
+//!     .comment_prefix(b"prefix".to_vec()) // Set read id prefix
+//!     .comment_suffix(b"suffix".to_vec()) // Set read id prefix
+//!     .build()
+//!     .unwrap();
+//!
+//! generator.create("test.fasta", &mut rng, 5)?; // Write five fasta record in "test.fasta"
+//! # Ok(())
+//! # }
+//! ```
 
 /* std use */
 
diff --git a/src/format/fastq.rs b/src/format/fastq.rs
index 012f830..abea96c 100644
--- a/src/format/fastq.rs
+++ b/src/format/fastq.rs
@@ -1,4 +1,60 @@
 //! Fastq generation
+//!
+//! Usage:
+//! ```
+//! use biotest::Format;
+//!
+//! # fn main() -> Result<(), biotest::error::Error> {
+//! let mut rng = biotest::rand(); // Create a random generator with a fixed seed
+//!
+//! let mut output = Vec::new();
+//! let generator = biotest::Fastq::builder().build().unwrap();
+//!
+//! generator.record(&mut output, &mut rng)?; // Write one fastq record in output
+//! generator.records(&mut output, &mut rng, 5)?; // Write five fastq records in output
+//!
+//! generator.create("test.fastq", &mut rng, 5)?; // Write five fastq record in "test.fasta"
+//! # Ok(())
+//! # }
+//! ```
+//!
+//! Read generate follow this template
+//! ```ignore
+//! >{id_prefix}{id}{id_suffix} {comment_prefix}{comment}{comment_suffix}
+//! {sequence}
+//! +{plus_prefix}{plus}{plus_suffix}
+//! {quality}
+//! ```
+//!
+//! Many think could be configurable with builder patern:
+//! ```
+//! use rand;
+//! use rand::SeedableRng;
+//! use biotest::Format;
+//!
+//! # fn main() -> Result<(), biotest::error::Error> {
+//! let mut rng = rand::rngs::StdRng::from_entropy(); // Create a random generator with a 'random' seed
+//!
+//! let generator = biotest::Fastq::builder()
+//!     .id(biotest::values::Alphabet::Lower) // Set alphabet use to generate sequence id
+//!     .id_len(10) // Set length of id
+//!     .id_prefix(b"prefix".to_vec()) // Set read id prefix
+//!     .id_suffix(b"suffix".to_vec()) // Set read id prefix
+//!     .comment(biotest::values::Alphabet::Upper) // Set alphabet use to generate sequence comment
+//!     .comment_len(0) // If comment length is set to 0 prefix and suffix isn't write
+//!     .comment_prefix(b"prefix".to_vec()) // Set read id prefix
+//!     .comment_suffix(b"suffix".to_vec()) // Set read id prefix
+//!     .plus(biotest::values::Alphabet::Upper) // Set alphabet use to generate sequence plus
+//!     .plus_len(0) // If plus length is set to 0 prefix and suffix isn't write
+//!     .plus_prefix(b"prefix".to_vec()) // Set read id prefix
+//!     .plus_suffix(b"suffix".to_vec()) // Set read id prefix
+//!     .build()
+//!     .unwrap();
+//!
+//! generator.create("test.fastq", &mut rng, 5)?; // Write five fasta record in "test.fastq"
+//! # Ok(())
+//! # }
+//! ```
 
 /* std use */
 
diff --git a/src/lib.rs b/src/lib.rs
index e8c4f1c..b204fe8 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -21,17 +21,19 @@ pub mod constants;
 pub mod values;
 #[macro_use]
 pub mod error;
-mod format;
+pub mod format;
 
 /* reexport */
+pub use format::Format;
+
 #[cfg(feature = "fasta")]
-pub use format::fasta;
+pub use format::fasta::Fasta;
 
 #[cfg(feature = "fastq")]
-pub use format::fastq;
+pub use format::fastq::Fastq;
 
 #[cfg(feature = "vcf")]
-pub use format::vcf;
+pub use format::vcf::Vcf;
 
 /// Create a random generator with [constants::SEED]
 pub fn rand() -> rand::rngs::StdRng {