diff --git a/bin/src/config.rs b/bin/src/config.rs
index a10e239..7764d60 100644
--- a/bin/src/config.rs
+++ b/bin/src/config.rs
@@ -8,7 +8,7 @@ use std::{
 use crate::{LintMap, dirs, err::ConfigErr, utils};
 
 use clap::Parser;
-use lib::{LINTS, session::Version};
+use lib::LINTS;
 use serde::{Deserialize, Serialize};
 use vfs::ReadOnlyVfs;
 
@@ -260,8 +260,6 @@ pub struct ConfFile {
     #[serde(default = "Vec::new")]
     disabled: Vec<String>,
 
-    nix_version: Option<String>,
-
     #[serde(default = "Vec::new")]
     pub ignore: Vec<String>,
 }
@@ -290,13 +288,8 @@ impl ConfFile {
     pub fn dump(&self) -> String {
         let ideal_config = {
             let disabled = vec![];
-            let nix_version = Some(utils::default_nix_version());
             let ignore = vec![".direnv".into()];
-            Self {
-                disabled,
-                nix_version,
-                ignore,
-            }
+            Self { disabled, ignore }
         };
         toml::ser::to_string_pretty(&ideal_config).unwrap()
     }
@@ -311,16 +304,6 @@ impl ConfFile {
                 .as_slice(),
         )
     }
-    pub fn version(&self) -> Result<Version, ConfigErr> {
-        if let Some(v) = &self.nix_version {
-            v.parse::<Version>()
-                .map_err(|()| ConfigErr::ConfFileVersionParse(v.clone()))
-        } else if let Some(v) = utils::get_version_info().and_then(|o| o.parse::<Version>().ok()) {
-            Ok(v)
-        } else {
-            Ok(utils::default_nix_version().parse::<Version>().unwrap())
-        }
-    }
 }
 
 fn parse_line_col(src: &str) -> Result<(usize, usize), ConfigErr> {
diff --git a/bin/src/fix.rs b/bin/src/fix.rs
index 6c18523..d14c806 100644
--- a/bin/src/fix.rs
+++ b/bin/src/fix.rs
@@ -2,7 +2,6 @@ use std::borrow::Cow;
 
 use crate::LintMap;
 
-use lib::session::SessionInfo;
 use rnix::TextRange;
 
 mod all;
@@ -17,7 +16,6 @@ pub struct FixResult<'a> {
     pub src: Source<'a>,
     pub fixed: Vec<Fixed>,
     pub lints: &'a LintMap,
-    pub sess: &'a SessionInfo,
 }
 
 #[derive(Debug, Clone)]
@@ -27,12 +25,11 @@ pub struct Fixed {
 }
 
 impl<'a> FixResult<'a> {
-    fn empty(src: Source<'a>, lints: &'a LintMap, sess: &'a SessionInfo) -> Self {
+    fn empty(src: Source<'a>, lints: &'a LintMap) -> Self {
         Self {
             src,
             fixed: Vec::new(),
             lints,
-            sess,
         }
     }
 }
@@ -47,7 +44,6 @@ pub mod main {
         err::{FixErr, StatixErr},
     };
 
-    use lib::session::SessionInfo;
     use similar::TextDiff;
 
     pub fn all(fix_config: &FixConfig) -> Result<(), StatixErr> {
@@ -55,15 +51,9 @@ pub mod main {
         let vfs = fix_config.vfs(conf_file.ignore.as_slice())?;
 
         let lints = conf_file.lints();
-        let version = conf_file.version()?;
-
-        let session = SessionInfo::from_version(version);
 
         for entry in vfs.iter() {
-            match (
-                fix_config.out(),
-                super::all_with(entry.contents, &lints, &session),
-            ) {
+            match (fix_config.out(), super::all_with(entry.contents, &lints)) {
                 (FixOut::Diff, fix_result) => {
                     let src = fix_result
                         .map(|r| r.src)
@@ -102,16 +92,7 @@ pub mod main {
         let original_src = entry.contents;
         let (line, col) = single_config.position;
 
-        let conf_file = ConfFile::discover(&single_config.conf_path)?;
-
-        let version = conf_file.version()?;
-
-        let session = SessionInfo::from_version(version);
-
-        match (
-            single_config.out(),
-            super::single(line, col, original_src, &session),
-        ) {
+        match (single_config.out(), super::single(line, col, original_src)) {
             (FixOut::Diff, single_result) => {
                 let fixed_src = single_result
                     .map(|r| r.src)
diff --git a/bin/src/fix/all.rs b/bin/src/fix/all.rs
index 730cd60..8a74465 100644
--- a/bin/src/fix/all.rs
+++ b/bin/src/fix/all.rs
@@ -1,6 +1,6 @@
 use std::borrow::Cow;
 
-use lib::{Report, session::SessionInfo};
+use lib::Report;
 use rnix::{Root, WalkEvent, parser::ParseError as RnixParseErr};
 use rowan::ast::AstNode as _;
 
@@ -9,11 +9,7 @@ use crate::{
     fix::{FixResult, Fixed},
 };
 
-fn collect_fixes(
-    source: &str,
-    lints: &LintMap,
-    sess: &SessionInfo,
-) -> Result<Vec<Report>, RnixParseErr> {
+fn collect_fixes(source: &str, lints: &LintMap) -> Result<Vec<Report>, RnixParseErr> {
     let parsed = Root::parse(source).ok()?;
 
     Ok(parsed
@@ -23,7 +19,7 @@ fn collect_fixes(
             WalkEvent::Enter(child) => lints.get(&child.kind()).map(|rules| {
                 rules
                     .iter()
-                    .filter_map(|rule| rule.validate(&child, sess))
+                    .filter_map(|rule| rule.validate(&child))
                     .filter(|report| report.total_suggestion_range().is_some())
                     .collect::<Vec<_>>()
             }),
@@ -62,7 +58,7 @@ fn reorder(mut reports: Vec<Report>) -> Vec<Report> {
 impl<'a> Iterator for FixResult<'a> {
     type Item = FixResult<'a>;
     fn next(&mut self) -> Option<Self::Item> {
-        let all_reports = collect_fixes(&self.src, self.lints, self.sess).ok()?;
+        let all_reports = collect_fixes(&self.src, self.lints).ok()?;
         if all_reports.is_empty() {
             return None;
         }
@@ -83,18 +79,13 @@ impl<'a> Iterator for FixResult<'a> {
             src: self.src.clone(),
             fixed,
             lints: self.lints,
-            sess: self.sess,
         })
     }
 }
 
-pub fn all_with<'a>(
-    src: &'a str,
-    lints: &'a LintMap,
-    sess: &'a SessionInfo,
-) -> Option<FixResult<'a>> {
+pub fn all_with<'a>(src: &'a str, lints: &'a LintMap) -> Option<FixResult<'a>> {
     let src = Cow::from(src);
     let _ = Root::parse(&src).ok().ok()?;
-    let initial = FixResult::empty(src, lints, sess);
+    let initial = FixResult::empty(src, lints);
     initial.into_iter().last()
 }
diff --git a/bin/src/fix/single.rs b/bin/src/fix/single.rs
index 971e0c3..5b8762d 100644
--- a/bin/src/fix/single.rs
+++ b/bin/src/fix/single.rs
@@ -1,6 +1,6 @@
 use std::{borrow::Cow, convert::TryFrom};
 
-use lib::{Report, session::SessionInfo};
+use lib::Report;
 use rnix::{Root, TextSize, WalkEvent};
 
 use crate::{err::SingleFixErr, fix::Source, utils};
@@ -27,7 +27,7 @@ fn pos_to_byte(line: usize, col: usize, src: &str) -> Result<TextSize, SingleFix
     }
 }
 
-fn find(offset: TextSize, src: &str, sess: &SessionInfo) -> Result<Report, SingleFixErr> {
+fn find(offset: TextSize, src: &str) -> Result<Report, SingleFixErr> {
     // we don't really need the source to form a completely parsed tree
     let parsed = Root::parse(src);
     let lints = utils::lint_map();
@@ -39,7 +39,7 @@ fn find(offset: TextSize, src: &str, sess: &SessionInfo) -> Result<Report, Singl
             WalkEvent::Enter(child) => lints.get(&child.kind()).map(|rules| {
                 rules
                     .iter()
-                    .filter_map(|rule| rule.validate(&child, sess))
+                    .filter_map(|rule| rule.validate(&child))
                     .find(|report| report.total_suggestion_range().is_some())
             }),
             WalkEvent::Leave(_) => None,
@@ -49,15 +49,10 @@ fn find(offset: TextSize, src: &str, sess: &SessionInfo) -> Result<Report, Singl
         .ok_or(SingleFixErr::NoOp)
 }
 
-pub fn single<'a>(
-    line: usize,
-    col: usize,
-    src: &'a str,
-    sess: &SessionInfo,
-) -> Result<SingleFixResult<'a>, SingleFixErr> {
+pub fn single(line: usize, col: usize, src: &str) -> Result<SingleFixResult<'_>, SingleFixErr> {
     let mut src = Cow::from(src);
     let offset = pos_to_byte(line, col, &src)?;
-    let report = find(offset, &src, sess)?;
+    let report = find(offset, &src)?;
 
     report.apply(src.to_mut());
 
diff --git a/bin/src/lint.rs b/bin/src/lint.rs
index 0309a8b..334d390 100644
--- a/bin/src/lint.rs
+++ b/bin/src/lint.rs
@@ -1,6 +1,6 @@
 use crate::{LintMap, utils};
 
-use lib::{Report, session::SessionInfo};
+use lib::Report;
 use rnix::{Root, WalkEvent};
 use vfs::{FileId, VfsEntry};
 
@@ -11,7 +11,7 @@ pub struct LintResult {
 }
 
 #[must_use]
-pub fn lint_with(vfs_entry: &VfsEntry, lints: &LintMap, sess: &SessionInfo) -> LintResult {
+pub fn lint_with(vfs_entry: &VfsEntry, lints: &LintMap) -> LintResult {
     let file_id = vfs_entry.file_id;
     let source = vfs_entry.contents;
     let parsed = Root::parse(source);
@@ -27,7 +27,7 @@ pub fn lint_with(vfs_entry: &VfsEntry, lints: &LintMap, sess: &SessionInfo) -> L
             WalkEvent::Enter(child) => lints.get(&child.kind()).map(|rules| {
                 rules
                     .iter()
-                    .filter_map(|rule| rule.validate(&child, sess))
+                    .filter_map(|rule| rule.validate(&child))
                     .collect::<Vec<_>>()
             }),
             WalkEvent::Leave(_) => None,
@@ -40,8 +40,8 @@ pub fn lint_with(vfs_entry: &VfsEntry, lints: &LintMap, sess: &SessionInfo) -> L
 }
 
 #[must_use]
-pub fn lint(vfs_entry: &VfsEntry, sess: &SessionInfo) -> LintResult {
-    lint_with(vfs_entry, &utils::lint_map(), sess)
+pub fn lint(vfs_entry: &VfsEntry) -> LintResult {
+    lint_with(vfs_entry, &utils::lint_map())
 }
 
 pub mod main {
@@ -54,19 +54,16 @@ pub mod main {
         traits::WriteDiagnostic,
     };
 
-    use lib::session::SessionInfo;
     use rayon::prelude::*;
 
     pub fn main(check_config: &CheckConfig) -> Result<(), StatixErr> {
         let conf_file = ConfFile::discover(&check_config.conf_path)?;
         let lints = conf_file.lints();
-        let version = conf_file.version()?;
-        let session = SessionInfo::from_version(version);
 
         let vfs = check_config.vfs(conf_file.ignore.as_slice())?;
 
         let mut stdout = io::stdout();
-        let lint = |vfs_entry| lint_with(&vfs_entry, &lints, &session);
+        let lint = |vfs_entry| lint_with(&vfs_entry, &lints);
         let results = vfs
             .par_iter()
             .map(lint)
diff --git a/bin/src/utils.rs b/bin/src/utils.rs
index 4c5296a..4c8ba56 100644
--- a/bin/src/utils.rs
+++ b/bin/src/utils.rs
@@ -24,17 +24,3 @@ pub fn lint_map_of(
 pub fn lint_map() -> HashMap<SyntaxKind, Vec<&'static Box<dyn Lint>>> {
     lint_map_of(&LINTS)
 }
-
-pub fn get_version_info() -> Option<String> {
-    use std::process::Command;
-    let program = Command::new("nix").arg("--version").output().ok()?;
-    std::str::from_utf8(&program.stdout)
-        .ok()?
-        .split(' ')
-        .nth(2)
-        .map(ToOwned::to_owned)
-}
-
-pub fn default_nix_version() -> String {
-    String::from("2.4")
-}
diff --git a/bin/tests/main.rs b/bin/tests/main.rs
index 5b3279c..da48707 100644
--- a/bin/tests/main.rs
+++ b/bin/tests/main.rs
@@ -1,19 +1,10 @@
 use std::path::Path;
 
-use lib::session::{SessionInfo, Version};
-
-macro_rules! session_info {
-    ($version:expr) => {{
-        let v: Version = $version.parse().unwrap();
-        SessionInfo::from_version(v)
-    }};
-}
-
 mod util {
     #[macro_export]
     macro_rules! test_lint {
-        ($tname:ident => $sess:expr, $($tail:tt)*) => {
-            test_lint!($tname => $sess);
+        ($tname:ident, $($tail:tt)*) => {
+            test_lint!($tname);
             test_lint!($($tail)*);
         };
         ($tname:ident, $($tail:tt)*) => {
@@ -21,15 +12,12 @@ mod util {
                 test_lint!($($tail)*);
         };
         ($tname:ident) => {
-            test_lint!($tname => session_info!("2.6"));
-        };
-        ($tname:ident => $sess:expr) => {
             paste::paste! {
                 #[test]
                 fn [<$tname _lint>](){
                     let file_path = concat!("data/", stringify!($tname), ".nix");
                     let contents = include_str!(concat!("data/", stringify!($tname), ".nix"));
-                    test_lint(&$sess, file_path, contents);
+                    test_lint(file_path, contents);
                 }
 
                 #[test]
@@ -43,18 +31,16 @@ mod util {
     }
 }
 
-fn test_lint(session: &SessionInfo, file_path: impl AsRef<Path>, contents: &str) {
+fn test_lint(file_path: impl AsRef<Path>, contents: &str) {
     use statix::{config::OutFormat, lint, traits::WriteDiagnostic};
     use vfs::ReadOnlyVfs;
 
     let vfs = ReadOnlyVfs::singleton(file_path, contents.as_bytes());
 
     let mut buffer = Vec::new();
-    vfs.iter()
-        .map(|entry| lint::lint(&entry, session))
-        .for_each(|r| {
-            buffer.write(&r, &vfs, OutFormat::StdErr).unwrap();
-        });
+    vfs.iter().map(|entry| lint::lint(&entry)).for_each(|r| {
+        buffer.write(&r, &vfs, OutFormat::StdErr).unwrap();
+    });
 
     let stripped = strip_ansi_escapes::strip(&buffer).unwrap();
     let out = std::str::from_utf8(&stripped).unwrap();
@@ -87,7 +73,7 @@ test_lint! {
     redundant_pattern_bind,
     unquoted_uri,
     empty_inherit,
-    deprecated_to_path => session_info!("2.4"),
+    deprecated_to_path,
     bool_simplification,
     useless_has_attr,
     repeated_keys,
diff --git a/lib/src/lib.rs b/lib/src/lib.rs
index e4849b7..35a8721 100644
--- a/lib/src/lib.rs
+++ b/lib/src/lib.rs
@@ -1,11 +1,9 @@
 #![recursion_limit = "1024"]
 mod lints;
 mod make;
-pub mod session;
 mod utils;
 
 pub use lints::LINTS;
-use session::SessionInfo;
 
 use rnix::{SyntaxElement, SyntaxKind, TextRange, parser::ParseError};
 use std::{convert::Into, default::Default};
@@ -249,7 +247,7 @@ impl Serialize for Suggestion {
 /// Lint logic is defined via this trait. Do not implement manually,
 /// look at the `lint` attribute macro instead for implementing rules
 pub trait Rule {
-    fn validate(&self, node: &SyntaxElement, sess: &SessionInfo) -> Option<Report>;
+    fn validate(&self, node: &SyntaxElement) -> Option<Report>;
 }
 
 /// Contains information about the lint itself. Do not implement manually,
diff --git a/lib/src/lints/bool_comparison.rs b/lib/src/lints/bool_comparison.rs
index af97262..ef95c60 100644
--- a/lib/src/lints/bool_comparison.rs
+++ b/lib/src/lints/bool_comparison.rs
@@ -1,4 +1,4 @@
-use crate::{Metadata, Report, Rule, Suggestion, make, session::SessionInfo};
+use crate::{Metadata, Report, Rule, Suggestion, make};
 
 use macros::lint;
 use rnix::{
@@ -35,7 +35,7 @@ use rowan::ast::AstNode as _;
 struct BoolComparison;
 
 impl Rule for BoolComparison {
-    fn validate(&self, node: &SyntaxElement, _sess: &SessionInfo) -> Option<Report> {
+    fn validate(&self, node: &SyntaxElement) -> Option<Report> {
         let NodeOrToken::Node(node) = node else {
             return None;
         };
diff --git a/lib/src/lints/bool_simplification.rs b/lib/src/lints/bool_simplification.rs
index 8cca34e..3bd689b 100644
--- a/lib/src/lints/bool_simplification.rs
+++ b/lib/src/lints/bool_simplification.rs
@@ -1,4 +1,4 @@
-use crate::{Metadata, Report, Rule, Suggestion, make, session::SessionInfo};
+use crate::{Metadata, Report, Rule, Suggestion, make};
 
 use macros::lint;
 use rnix::{
@@ -32,7 +32,7 @@ use rowan::ast::AstNode as _;
 struct BoolSimplification;
 
 impl Rule for BoolSimplification {
-    fn validate(&self, node: &SyntaxElement, _sess: &SessionInfo) -> Option<Report> {
+    fn validate(&self, node: &SyntaxElement) -> Option<Report> {
         let NodeOrToken::Node(node) = node else {
             return None;
         };
diff --git a/lib/src/lints/collapsible_let_in.rs b/lib/src/lints/collapsible_let_in.rs
index cac075b..15f08ff 100644
--- a/lib/src/lints/collapsible_let_in.rs
+++ b/lib/src/lints/collapsible_let_in.rs
@@ -1,4 +1,4 @@
-use crate::{Metadata, Report, Rule, Suggestion, session::SessionInfo};
+use crate::{Metadata, Report, Rule, Suggestion};
 
 use macros::lint;
 use rnix::{
@@ -44,7 +44,7 @@ use rowan::{Direction, ast::AstNode as _};
 struct CollapsibleLetIn;
 
 impl Rule for CollapsibleLetIn {
-    fn validate(&self, node: &SyntaxElement, _sess: &SessionInfo) -> Option<Report> {
+    fn validate(&self, node: &SyntaxElement) -> Option<Report> {
         let NodeOrToken::Node(node) = node else {
             return None;
         };
diff --git a/lib/src/lints/deprecated_to_path.rs b/lib/src/lints/deprecated_to_path.rs
index 768bcdd..70ca604 100644
--- a/lib/src/lints/deprecated_to_path.rs
+++ b/lib/src/lints/deprecated_to_path.rs
@@ -1,4 +1,4 @@
-use crate::{Metadata, Report, Rule, session::SessionInfo};
+use crate::{Metadata, Report, Rule};
 
 use macros::lint;
 use rnix::{NodeOrToken, SyntaxElement, SyntaxKind, ast::Apply};
@@ -38,7 +38,7 @@ struct DeprecatedToPath;
 static ALLOWED_PATHS: &[&str; 2] = &["builtins.toPath", "toPath"];
 
 impl Rule for DeprecatedToPath {
-    fn validate(&self, node: &SyntaxElement, _sess: &SessionInfo) -> Option<Report> {
+    fn validate(&self, node: &SyntaxElement) -> Option<Report> {
         if let NodeOrToken::Node(node) = node
             && let Some(apply) = Apply::cast(node.clone())
             && let lambda_path = apply.lambda()?.to_string()
diff --git a/lib/src/lints/empty_inherit.rs b/lib/src/lints/empty_inherit.rs
index 6986c1e..619a239 100644
--- a/lib/src/lints/empty_inherit.rs
+++ b/lib/src/lints/empty_inherit.rs
@@ -1,4 +1,4 @@
-use crate::{Metadata, Report, Rule, Suggestion, session::SessionInfo, utils};
+use crate::{Metadata, Report, Rule, Suggestion, utils};
 
 use macros::lint;
 use rnix::{NodeOrToken, SyntaxElement, SyntaxKind, ast::Inherit};
@@ -26,7 +26,7 @@ use rowan::ast::AstNode as _;
 struct EmptyInherit;
 
 impl Rule for EmptyInherit {
-    fn validate(&self, node: &SyntaxElement, _sess: &SessionInfo) -> Option<Report> {
+    fn validate(&self, node: &SyntaxElement) -> Option<Report> {
         let NodeOrToken::Node(node) = node else {
             return None;
         };
diff --git a/lib/src/lints/empty_let_in.rs b/lib/src/lints/empty_let_in.rs
index 73d2de2..6ff0225 100644
--- a/lib/src/lints/empty_let_in.rs
+++ b/lib/src/lints/empty_let_in.rs
@@ -1,4 +1,4 @@
-use crate::{Metadata, Report, Rule, Suggestion, session::SessionInfo};
+use crate::{Metadata, Report, Rule, Suggestion};
 
 use macros::lint;
 use rnix::{
@@ -34,7 +34,7 @@ use rowan::ast::AstNode as _;
 struct EmptyLetIn;
 
 impl Rule for EmptyLetIn {
-    fn validate(&self, node: &SyntaxElement, _sess: &SessionInfo) -> Option<Report> {
+    fn validate(&self, node: &SyntaxElement) -> Option<Report> {
         if let NodeOrToken::Node(node) = node
             && let Some(let_in_expr) = LetIn::cast(node.clone())
             && let entries = let_in_expr.entries()
diff --git a/lib/src/lints/empty_list_concat.rs b/lib/src/lints/empty_list_concat.rs
index 4c9e9d7..765dedc 100644
--- a/lib/src/lints/empty_list_concat.rs
+++ b/lib/src/lints/empty_list_concat.rs
@@ -1,4 +1,4 @@
-use crate::{Metadata, Report, Rule, Suggestion, session::SessionInfo};
+use crate::{Metadata, Report, Rule, Suggestion};
 
 use macros::lint;
 use rnix::{
@@ -32,7 +32,7 @@ use rowan::ast::AstNode as _;
 struct EmptyListConcat;
 
 impl Rule for EmptyListConcat {
-    fn validate(&self, node: &SyntaxElement, _sess: &SessionInfo) -> Option<Report> {
+    fn validate(&self, node: &SyntaxElement) -> Option<Report> {
         let NodeOrToken::Node(node) = node else {
             return None;
         };
diff --git a/lib/src/lints/empty_pattern.rs b/lib/src/lints/empty_pattern.rs
index 48feaa6..2f8db81 100644
--- a/lib/src/lints/empty_pattern.rs
+++ b/lib/src/lints/empty_pattern.rs
@@ -1,4 +1,4 @@
-use crate::{Metadata, Report, Rule, Suggestion, make, session::SessionInfo};
+use crate::{Metadata, Report, Rule, Suggestion, make};
 
 use macros::lint;
 use rnix::{
@@ -41,7 +41,7 @@ use rowan::ast::AstNode as _;
 struct EmptyPattern;
 
 impl Rule for EmptyPattern {
-    fn validate(&self, node: &SyntaxElement, _sess: &SessionInfo) -> Option<Report> {
+    fn validate(&self, node: &SyntaxElement) -> Option<Report> {
         let NodeOrToken::Node(node) = node else {
             return None;
         };
diff --git a/lib/src/lints/eta_reduction.rs b/lib/src/lints/eta_reduction.rs
index c9135d2..59b441a 100644
--- a/lib/src/lints/eta_reduction.rs
+++ b/lib/src/lints/eta_reduction.rs
@@ -1,4 +1,4 @@
-use crate::{Metadata, Report, Rule, Suggestion, session::SessionInfo};
+use crate::{Metadata, Report, Rule, Suggestion};
 
 use macros::lint;
 use rnix::{
@@ -42,7 +42,7 @@ use rowan::ast::AstNode as _;
 struct EtaReduction;
 
 impl Rule for EtaReduction {
-    fn validate(&self, node: &SyntaxElement, _sess: &SessionInfo) -> Option<Report> {
+    fn validate(&self, node: &SyntaxElement) -> Option<Report> {
         let NodeOrToken::Node(node) = node else {
             return None;
         };
diff --git a/lib/src/lints/legacy_let_syntax.rs b/lib/src/lints/legacy_let_syntax.rs
index 8b3fd7d..a656140 100644
--- a/lib/src/lints/legacy_let_syntax.rs
+++ b/lib/src/lints/legacy_let_syntax.rs
@@ -1,4 +1,4 @@
-use crate::{Metadata, Report, Rule, Suggestion, make, session::SessionInfo};
+use crate::{Metadata, Report, Rule, Suggestion, make};
 
 use macros::lint;
 use rnix::{
@@ -44,7 +44,7 @@ use rowan::ast::AstNode as _;
 struct ManualInherit;
 
 impl Rule for ManualInherit {
-    fn validate(&self, node: &SyntaxElement, _sess: &SessionInfo) -> Option<Report> {
+    fn validate(&self, node: &SyntaxElement) -> Option<Report> {
         let NodeOrToken::Node(node) = node else {
             return None;
         };
diff --git a/lib/src/lints/manual_inherit.rs b/lib/src/lints/manual_inherit.rs
index be61720..3d66910 100644
--- a/lib/src/lints/manual_inherit.rs
+++ b/lib/src/lints/manual_inherit.rs
@@ -1,4 +1,4 @@
-use crate::{Metadata, Report, Rule, Suggestion, make, session::SessionInfo};
+use crate::{Metadata, Report, Rule, Suggestion, make};
 
 use macros::lint;
 use rnix::{
@@ -40,7 +40,7 @@ use rowan::ast::AstNode as _;
 struct ManualInherit;
 
 impl Rule for ManualInherit {
-    fn validate(&self, node: &SyntaxElement, _sess: &SessionInfo) -> Option<Report> {
+    fn validate(&self, node: &SyntaxElement) -> Option<Report> {
         let NodeOrToken::Node(node) = node else {
             return None;
         };
diff --git a/lib/src/lints/manual_inherit_from.rs b/lib/src/lints/manual_inherit_from.rs
index 239d81a..83d1075 100644
--- a/lib/src/lints/manual_inherit_from.rs
+++ b/lib/src/lints/manual_inherit_from.rs
@@ -1,4 +1,4 @@
-use crate::{Metadata, Report, Rule, Suggestion, make, session::SessionInfo};
+use crate::{Metadata, Report, Rule, Suggestion, make};
 
 use macros::lint;
 use rnix::{
@@ -40,7 +40,7 @@ use rowan::ast::AstNode as _;
 struct ManualInherit;
 
 impl Rule for ManualInherit {
-    fn validate(&self, node: &SyntaxElement, _sess: &SessionInfo) -> Option<Report> {
+    fn validate(&self, node: &SyntaxElement) -> Option<Report> {
         let NodeOrToken::Node(node) = node else {
             return None;
         };
diff --git a/lib/src/lints/redundant_pattern_bind.rs b/lib/src/lints/redundant_pattern_bind.rs
index 1c59c62..fec7c48 100644
--- a/lib/src/lints/redundant_pattern_bind.rs
+++ b/lib/src/lints/redundant_pattern_bind.rs
@@ -1,4 +1,4 @@
-use crate::{Metadata, Report, Rule, Suggestion, session::SessionInfo};
+use crate::{Metadata, Report, Rule, Suggestion};
 
 use macros::lint;
 use rnix::{NodeOrToken, SyntaxElement, SyntaxKind, ast::Pattern};
@@ -32,7 +32,7 @@ use rowan::ast::AstNode as _;
 struct RedundantPatternBind;
 
 impl Rule for RedundantPatternBind {
-    fn validate(&self, node: &SyntaxElement, _sess: &SessionInfo) -> Option<Report> {
+    fn validate(&self, node: &SyntaxElement) -> Option<Report> {
         let NodeOrToken::Node(node) = node else {
             return None;
         };
diff --git a/lib/src/lints/repeated_keys.rs b/lib/src/lints/repeated_keys.rs
index d7c71dc..6425a58 100644
--- a/lib/src/lints/repeated_keys.rs
+++ b/lib/src/lints/repeated_keys.rs
@@ -1,6 +1,6 @@
 use std::fmt::Write as _;
 
-use crate::{Metadata, Report, Rule, session::SessionInfo};
+use crate::{Metadata, Report, Rule};
 
 use macros::lint;
 use rnix::{
@@ -45,7 +45,7 @@ use rowan::ast::AstNode as _;
 struct RepeatedKeys;
 
 impl Rule for RepeatedKeys {
-    fn validate(&self, node: &SyntaxElement, _sess: &SessionInfo) -> Option<Report> {
+    fn validate(&self, node: &SyntaxElement) -> Option<Report> {
         let NodeOrToken::Node(node) = node else {
             return None;
         };
diff --git a/lib/src/lints/unquoted_uri.rs b/lib/src/lints/unquoted_uri.rs
index d46d03d..dde2164 100644
--- a/lib/src/lints/unquoted_uri.rs
+++ b/lib/src/lints/unquoted_uri.rs
@@ -1,4 +1,4 @@
-use crate::{Metadata, Report, Rule, Suggestion, make, session::SessionInfo};
+use crate::{Metadata, Report, Rule, Suggestion, make};
 use rowan::ast::AstNode as _;
 
 use macros::lint;
@@ -46,7 +46,7 @@ use rnix::{NodeOrToken, SyntaxElement, SyntaxKind};
 struct UnquotedUri;
 
 impl Rule for UnquotedUri {
-    fn validate(&self, node: &SyntaxElement, _sess: &SessionInfo) -> Option<Report> {
+    fn validate(&self, node: &SyntaxElement) -> Option<Report> {
         let NodeOrToken::Token(token) = node else {
             return None;
         };
diff --git a/lib/src/lints/useless_has_attr.rs b/lib/src/lints/useless_has_attr.rs
index 8f2a9ac..df08b23 100644
--- a/lib/src/lints/useless_has_attr.rs
+++ b/lib/src/lints/useless_has_attr.rs
@@ -1,4 +1,4 @@
-use crate::{Metadata, Report, Rule, Suggestion, make, session::SessionInfo};
+use crate::{Metadata, Report, Rule, Suggestion, make};
 
 use macros::lint;
 use rnix::{
@@ -33,7 +33,7 @@ use rowan::ast::AstNode as _;
 struct UselessHasAttr;
 
 impl Rule for UselessHasAttr {
-    fn validate(&self, node: &SyntaxElement, _sess: &SessionInfo) -> Option<Report> {
+    fn validate(&self, node: &SyntaxElement) -> Option<Report> {
         let NodeOrToken::Node(node) = node else {
             return None;
         };
diff --git a/lib/src/lints/useless_parens.rs b/lib/src/lints/useless_parens.rs
index 6234769..74028e7 100644
--- a/lib/src/lints/useless_parens.rs
+++ b/lib/src/lints/useless_parens.rs
@@ -1,4 +1,4 @@
-use crate::{Diagnostic, Metadata, Report, Rule, Suggestion, session::SessionInfo};
+use crate::{Diagnostic, Metadata, Report, Rule, Suggestion};
 
 use macros::lint;
 use rnix::{
@@ -45,7 +45,7 @@ use rowan::ast::AstNode as _;
 struct UselessParens;
 
 impl Rule for UselessParens {
-    fn validate(&self, node: &SyntaxElement, _sess: &SessionInfo) -> Option<Report> {
+    fn validate(&self, node: &SyntaxElement) -> Option<Report> {
         let NodeOrToken::Node(node) = node else {
             return None;
         };
diff --git a/lib/src/session.rs b/lib/src/session.rs
deleted file mode 100644
index 3d9b52c..0000000
--- a/lib/src/session.rs
+++ /dev/null
@@ -1,96 +0,0 @@
-use std::{cmp::Ordering, str::FromStr};
-
-#[derive(Copy, Clone, Debug, Eq, PartialEq)]
-pub struct Version {
-    major: u16,
-    minor: u16,
-    patch: Option<u16>,
-}
-
-impl Ord for Version {
-    fn cmp(&self, other: &Self) -> Ordering {
-        let score = |v: &Version| v.major * 100 + v.minor * 10 + v.patch.unwrap_or(0);
-        score(self).cmp(&score(other))
-    }
-}
-
-impl PartialOrd for Version {
-    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
-        Some(self.cmp(other))
-    }
-}
-
-fn parse_number(s: &str) -> Option<u16> {
-    s.chars()
-        .take_while(char::is_ascii_digit)
-        .collect::<String>()
-        .parse::<u16>()
-        .ok()
-}
-
-fn parse_version(s: &str) -> Option<Version> {
-    let mut parts = s.split('.');
-    let major = parse_number(parts.next()?)?;
-    let minor = parse_number(parts.next()?)?;
-    let patch = parts.next().and_then(parse_number);
-    Some(Version {
-        major,
-        minor,
-        patch,
-    })
-}
-
-impl FromStr for Version {
-    type Err = ();
-    fn from_str(s: &str) -> Result<Self, Self::Err> {
-        parse_version(s).ok_or(())
-    }
-}
-
-#[non_exhaustive]
-pub struct SessionInfo {
-    nix_version: Version,
-}
-
-impl SessionInfo {
-    #[must_use]
-    pub fn from_version(nix_version: Version) -> Self {
-        Self { nix_version }
-    }
-
-    #[must_use]
-    pub fn version(&self) -> &Version {
-        &self.nix_version
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn parse_trivial() {
-        let v = "1.6.1".parse::<Version>().ok();
-        assert!(v.is_some());
-    }
-
-    #[test]
-    fn parse() {
-        let v = "2.4pre20211006_53e4794".parse::<Version>().ok();
-        assert!(v.is_some());
-    }
-
-    #[test]
-    fn compare_trivial() {
-        let v1 = "1.6.1".parse::<Version>().ok();
-        let v2 = "1.7.2".parse::<Version>().ok();
-        assert!(v2 > v1);
-    }
-
-    #[test]
-    fn compare() {
-        let v1 = "1.7".parse::<Version>().ok();
-        let v2 = "2.4pre20211006_53e4794".parse::<Version>().ok();
-        assert!(v2 >= v1);
-    }
-}