diff --git a/Cargo.lock b/Cargo.lock
index 5ce011f..2da0efa 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2,6 +2,46 @@
 # It is not intended for manual editing.
 version = 3
 
+[[package]]
+name = "aho-corasick"
+version = "1.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8e60d3430d3a69478ad0993f19238d2df97c507009a52b3c10addcd7f6bcb916"
+dependencies = [
+ "memchr",
+]
+
+[[package]]
+name = "anyhow"
+version = "1.0.86"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b3d1d046238990b9cf5bcde22a3fb3584ee5cf65fb2765f454ed428c7a0063da"
+
+[[package]]
+name = "memchr"
+version = "2.7.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "78ca9ab1a0babb1e7d5695e3530886289c18cf2f87ec19a575a0abdce112e3a3"
+
+[[package]]
+name = "regex-automata"
+version = "0.4.7"
+source = "git+https://github.com/f-forcher/regex?branch=expose-state-iter#cdc3eb10549fc9ce0da2dd6a047c1e26aebdc9ef"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-syntax",
+]
+
+[[package]]
+name = "regex-syntax"
+version = "0.8.4"
+source = "git+https://github.com/f-forcher/regex?branch=expose-state-iter#cdc3eb10549fc9ce0da2dd6a047c1e26aebdc9ef"
+
 [[package]]
 name = "structured-gen-rust"
 version = "0.1.0"
+dependencies = [
+ "anyhow",
+ "regex-automata",
+]
diff --git a/Cargo.toml b/Cargo.toml
index b48d2f5..885619b 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -4,3 +4,8 @@ version = "0.1.0"
 edition = "2021"
 
 [dependencies]
+anyhow = "1.0.86"
+regex-automata = "0.4.7"
+
+[patch.crates-io]
+regex-automata = { git = 'https://github.com/f-forcher/regex', branch = 'expose-state-iter' }
diff --git a/src/main.rs b/src/main.rs
index e7a11a9..85d9ecb 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,3 +1,34 @@
-fn main() {
-    println!("Hello, world!");
+use anyhow::Result;
+use regex_automata::{
+    dfa::{dense, Automaton},
+    Anchored, Input,
+};
+
+fn main() -> Result<()> {
+    let dfa = dense::DFA::new(r"[0-9]*\.?[0-9]*")?;
+    let haystack = "1.34";
+
+    // The start state is determined by inspecting the position and the
+    // initial bytes of the haystack.
+    let mut state = dfa.start_state_forward(&Input::new(haystack).anchored(Anchored::Yes))?;
+    // Walk all the bytes in the haystack.
+    for &b in haystack.as_bytes().iter() {
+        state = dfa.next_state(state, b);
+    }
+
+    let states_num = dfa.tt.len();
+
+    println!("There are {} states in this dfa", states_num);
+
+    let states_ids: Vec<_> = dfa.tt.states().map(|state| state.id()).collect();
+
+    println!("Their IDs are {:?}", states_ids);
+
+    // DFAs in this crate require an explicit
+    // end-of-input transition if a search reaches
+    // the end of a haystack.
+    state = dfa.next_eoi_state(state);
+    assert!(dfa.is_match_state(state));
+
+    Ok(())
 }