feat(build): add flat-bin kind and FAT [archive] packing for OS-dev

src/core/build/archive.rs

@@ -0,0 +1,272 @@
+// DCR — Cargo-like C/C++ project manager.
+//
+// Copyright (C) 2026 Dexoron (Bezotechestvo Vladimir) <main@dexoron.su>
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+use crate::core::build_config::ArchiveConfig;
+use fatfs::{FileSystem, FormatVolumeOptions, format_volume};
+use glob::glob;
+use std::fs::{self, File, OpenOptions};
+use std::io::{self, Read, Seek, SeekFrom, Write};
+use std::path::Path;
+
+struct OffsetFile<T> {
+    inner: T,
+    offset: u64,
+}
+
+impl<T: Read> Read for OffsetFile<T> {
+    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
+        self.inner.read(buf)
+    }
+}
+
+impl<T: Write> Write for OffsetFile<T> {
+    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
+        self.inner.write(buf)
+    }
+    fn flush(&mut self) -> io::Result<()> {
+        self.inner.flush()
+    }
+}
+
+impl<T: Seek> Seek for OffsetFile<T> {
+    fn seek(&mut self, pos: SeekFrom) -> io::Result<u64> {
+        match pos {
+            SeekFrom::Start(n) => {
+                let actual = self.inner.seek(SeekFrom::Start(n + self.offset))?;
+                if actual < self.offset {
+                    Ok(0)
+                } else {
+                    Ok(actual - self.offset)
+                }
+            }
+            SeekFrom::Current(n) => {
+                let actual = self.inner.seek(SeekFrom::Current(n))?;
+                if actual < self.offset {
+                    Ok(0)
+                } else {
+                    Ok(actual - self.offset)
+                }
+            }
+            SeekFrom::End(n) => {
+                let actual = self.inner.seek(SeekFrom::End(n))?;
+                if actual < self.offset {
+                    Ok(0)
+                } else {
+                    Ok(actual - self.offset)
+                }
+            }
+        }
+    }
+}
+
+fn parse_size(s: &str) -> Result<u64, String> {
+    let s = s.trim();
+    if s.is_empty() {
+        return Ok(0);
+    }
+    let mut num_str = String::new();
+    let mut unit = String::new();
+    for c in s.chars() {
+        if c.is_ascii_digit() || c == '.' {
+            num_str.push(c);
+        } else {
+            unit.push(c);
+        }
+    }
+    let val: f64 = num_str
+        .parse()
+        .map_err(|_| format!("invalid size number: {num_str}"))?;
+    let unit = unit.trim().to_lowercase();
+    let multiplier = match unit.as_str() {
+        "k" | "kb" => 1024.0,
+        "m" | "mb" => 1024.0 * 1024.0,
+        "g" | "gb" => 1024.0 * 1024.0 * 1024.0,
+        "" => 1.0,
+        _ => return Err(format!("unknown unit: {unit}")),
+    };
+    Ok((val * multiplier) as u64)
+}
+
+pub fn pack_archive(
+    project_root: &Path,
+    config: &ArchiveConfig,
+    profile: &str,
+) -> Result<(), String> {
+    let output_substituted = config.output.replace("{profile}", profile);
+    let output_path = project_root.join(&output_substituted);
+    if let Some(parent) = output_path.parent() {
+        fs::create_dir_all(parent)
+            .map_err(|e| format!("failed to create output parent dir: {e}"))?;
+    }
+
+    let size = if let Some(sz_str) = &config.size {
+        parse_size(sz_str)?
+    } else {
+        1474560
+    };
+
+    let offset = if let Some(off_str) = &config.offset {
+        parse_size(off_str)?
+    } else {
+        0
+    };
+
+    let mut file = OpenOptions::new()
+        .read(true)
+        .write(true)
+        .create(true)
+        .truncate(false)
+        .open(&output_path)
+        .map_err(|e| format!("failed to open output file: {e}"))?;
+
+    let current_len = file.metadata().map(|m| m.len()).unwrap_or(0);
+    if current_len < size {
+        file.set_len(size)
+            .map_err(|e| format!("failed to set image file size: {e}"))?;
+    }
+
+    if offset == 0
+        && let Some(boot_rel) = &config.bootsector
+    {
+        let boot_rel_substituted = boot_rel.replace("{profile}", profile);
+        let boot_path = project_root.join(&boot_rel_substituted);
+        if boot_path.is_file() {
+            let mut boot_file =
+                File::open(&boot_path).map_err(|e| format!("failed to open bootsector: {e}"))?;
+            let mut boot_bytes = vec![0; 512];
+            let _ = boot_file
+                .read(&mut boot_bytes)
+                .map_err(|e| format!("failed to read bootsector: {e}"))?;
+            file.seek(SeekFrom::Start(0))
+                .map_err(|e| format!("failed to seek to start: {e}"))?;
+            file.write_all(&boot_bytes)
+                .map_err(|e| format!("failed to write bootsector: {e}"))?;
+        }
+    }
+
+    file.seek(SeekFrom::Start(0))
+        .map_err(|e| format!("failed to seek to start: {e}"))?;
+
+    let mut wrapper = OffsetFile {
+        inner: file,
+        offset,
+    };
+
+    let label = config.label.as_deref().unwrap_or("VOLUME");
+    let mut label_bytes = [b' '; 11];
+    let bytes_to_copy = label.len().min(11);
+    label_bytes[..bytes_to_copy].copy_from_slice(&label.as_bytes()[..bytes_to_copy]);
+
+    let fat_type = match config.format.to_lowercase().as_str() {
+        "fat12" => Some(fatfs::FatType::Fat12),
+        "fat16" => Some(fatfs::FatType::Fat16),
+        "fat32" => Some(fatfs::FatType::Fat32),
+        _ => None,
+    };
+
+    let mut options = FormatVolumeOptions::new().volume_label(label_bytes);
+    if let Some(t) = fat_type {
+        options = options.fat_type(t);
+    }
+
+    format_volume(&mut wrapper, options)
+        .map_err(|e| format!("failed to format FAT volume: {e}"))?;
+
+    wrapper
+        .seek(SeekFrom::Start(0))
+        .map_err(|e| format!("failed to seek to start after format: {e}"))?;
+
+    let fs = FileSystem::new(wrapper, fatfs::FsOptions::new())
+        .map_err(|e| format!("failed to mount FAT fs: {e}"))?;
+    let root_dir = fs.root_dir();
+
+    for layout in &config.layout {
+        let from_substituted = layout.from.replace("{profile}", profile);
+        let from_pattern = project_root
+            .join(&from_substituted)
+            .to_string_lossy()
+            .to_string();
+
+        let paths = if from_pattern.contains('*') || from_pattern.contains('?') {
+            let mut matched = Vec::new();
+            if let Ok(entries) = glob(&from_pattern) {
+                for path in entries.flatten() {
+                    matched.push(path);
+                }
+            }
+            matched
+        } else {
+            let p = project_root.join(&from_substituted);
+            if p.exists() { vec![p] } else { Vec::new() }
+        };
+
+        for path in paths {
+            if !path.is_file() {
+                continue;
+            }
+            let filename = path.file_name().and_then(|n| n.to_str()).unwrap_or("");
+            if filename.is_empty() {
+                continue;
+            }
+
+            let mut target_filename = filename.to_string();
+            let mut target_dir_str = layout.to.trim_matches('/');
+
+            let is_glob = from_pattern.contains('*') || from_pattern.contains('?');
+            if !is_glob
+                && !layout.to.ends_with('/')
+                && let Some(last_part) = Path::new(&layout.to).file_name().and_then(|n| n.to_str())
+                && last_part.contains('.')
+            {
+                target_filename = last_part.to_string();
+                let parent_path = Path::new(&layout.to).parent().unwrap_or(Path::new(""));
+                target_dir_str = parent_path.to_str().unwrap_or("").trim_matches('/');
+            }
+
+            let mut current_dir = root_dir.clone();
+            if !target_dir_str.is_empty() {
+                let parts = target_dir_str.split('/');
+                for part in parts {
+                    if part.is_empty() {
+                        continue;
+                    }
+                    current_dir = match current_dir.open_dir(part) {
+                        Ok(dir) => dir,
+                        Err(_) => current_dir
+                            .create_dir(part)
+                            .map_err(|e| format!("failed to create dir {part}: {e}"))?,
+                    };
+                }
+            }
+
+            let mut out_file = current_dir
+                .create_file(&target_filename)
+                .map_err(|e| format!("failed to create file {target_filename}: {e}"))?;
+            let mut in_file =
+                File::open(&path).map_err(|e| format!("failed to open input file: {e}"))?;
+            let mut buffer = Vec::new();
+            in_file
+                .read_to_end(&mut buffer)
+                .map_err(|e| format!("failed to read input file: {e}"))?;
+            out_file
+                .write_all(&buffer)
+                .map_err(|e| format!("failed to write to FAT file {target_filename}: {e}"))?;
+        }
+    }
+
+    Ok(())
+}

src/core/build/builder/artifact.rs

@@ -19,9 +19,130 @@ use crate::core::build::builder::BuildContext;
 use crate::core::build::common;
 use crate::platform;
 use crate::utils::build::is_bare_metal_target;
+use std::path::{Path, PathBuf};
 use std::process::Command;
 use std::time::Instant;
 
+pub(crate) fn artifact_dir(ctx: &BuildContext) -> PathBuf {
+    match ctx.target_dir {
+        Some(dir) => Path::new(dir).to_path_buf(),
+        None => Path::new("./target").join(ctx.profile),
+    }
+}
+
+pub(crate) fn flat_output_path(ctx: &BuildContext) -> String {
+    let name = ctx.output_filename.unwrap_or(ctx.project_name);
+    let ext = ctx.output_extension.unwrap_or("bin");
+    let file = if ext.is_empty() {
+        name.to_string()
+    } else {
+        format!("{name}.{ext}")
+    };
+    artifact_dir(ctx).join(file).to_string_lossy().to_string()
+}
+
+pub(crate) fn flat_source_output_path(ctx: &BuildContext, source: &str) -> String {
+    let stem = Path::new(source)
+        .file_stem()
+        .and_then(|s| s.to_str())
+        .unwrap_or("out");
+    let ext = ctx.output_extension.unwrap_or("bin");
+    let file = if ext.is_empty() {
+        stem.to_string()
+    } else {
+        format!("{stem}.{ext}")
+    };
+    artifact_dir(ctx).join(file).to_string_lossy().to_string()
+}
+
+fn resolve_objcopy() -> Result<String, String> {
+    for candidate in ["llvm-objcopy", "objcopy", "gobjcopy"] {
+        if Command::new(candidate)
+            .arg("--version")
+            .output()
+            .map(|o| o.status.success())
+            .unwrap_or(false)
+        {
+            return Ok(candidate.to_string());
+        }
+    }
+    Err(
+        "flat-bin requires llvm-objcopy, objcopy, or gobjcopy in PATH \
+         (install binutils or LLVM tools)"
+            .to_string(),
+    )
+}
+
+pub(crate) fn objcopy_binary(ctx: &BuildContext, input: &str, output: &str) -> Result<(), String> {
+    if let Some(parent) = Path::new(output).parent() {
+        std::fs::create_dir_all(parent).map_err(|e| format!("output dir error: {e}"))?;
+    }
+    if !common::needs_rebuild(input, output) {
+        return Ok(());
+    }
+    let tool = resolve_objcopy()?;
+    let mut cmd = Command::new(&tool);
+    cmd.arg("-O").arg("binary").arg(input).arg(output);
+    if ctx.verbose || std::env::var("DCR_DEBUG").is_ok() {
+        eprintln!("[dcr] {:?}", cmd);
+    }
+    common::run_command_sync_output(&mut cmd)
+}
+
+pub(crate) fn link_flat_binary(
+    ctx: &BuildContext,
+    objects: &[String],
+    default_linker: &str,
+    start_time: Instant,
+) -> Result<f64, String> {
+    let out_path = flat_output_path(ctx);
+    if !common::needs_link(objects, &out_path) {
+        return Ok(common::elapsed_secs(start_time));
+    }
+
+    let intermediate = {
+        let dir = match ctx.target_dir {
+            Some(dir) => Path::new(dir).join("obj"),
+            None => Path::new("./target").join(ctx.profile).join("obj"),
+        };
+        std::fs::create_dir_all(&dir).map_err(|e| format!("obj dir error: {e}"))?;
+        dir.join(format!("{}.flat.elf", ctx.project_name))
+            .to_string_lossy()
+            .to_string()
+    };
+
+    let mut cmd = Command::new(ctx.linker.unwrap_or(default_linker));
+    cmd.arg("-nostdlib").arg("-static");
+    for obj in objects {
+        cmd.arg(obj);
+    }
+    for dir in ctx.lib_dirs {
+        cmd.arg(format!("-L{dir}"));
+    }
+    for lib in ctx.libs {
+        cmd.arg(format!("-l{lib}"));
+    }
+    for flag in ctx.ldflags {
+        cmd.arg(flag);
+    }
+    cmd.arg("-o").arg(&intermediate);
+
+    if ctx.verbose || std::env::var("DCR_DEBUG").is_ok() {
+        eprintln!("[dcr] {:?}", cmd);
+    }
+    let output = cmd.output().map_err(|err| format!("Build failed: {err}"))?;
+    if !output.status.success() {
+        let stderr = String::from_utf8_lossy(&output.stderr);
+        let stdout = String::from_utf8_lossy(&output.stdout);
+        return Err(format!(
+            "flat-bin link failed:\nstdout: {stdout}\nstderr: {stderr}"
+        ));
+    }
+
+    objcopy_binary(ctx, &intermediate, &out_path)?;
+    Ok(common::elapsed_secs(start_time))
+}
+
 pub(crate) fn archive_static(
     ctx: &BuildContext,
     objects: &[String],
@@ -56,6 +177,10 @@ pub(crate) fn link_binary(
     default_linker: &str,
     start_time: Instant,
 ) -> Result<f64, String> {
+    if crate::utils::build::is_flat_bin(ctx.kind) {
+        return link_flat_binary(ctx, objects, default_linker, start_time);
+    }
+
     let mut cmd = Command::new(ctx.linker.unwrap_or(default_linker));
     if ctx.kind == "sharedlib" {
         if cfg!(target_os = "macos") {

src/core/build/builder/cc_common.rs

@@ -18,7 +18,7 @@
 use crate::core::build::builder::BuildContext;
 use crate::core::build::builder::artifact;
 use crate::core::build::common;
-use crate::utils::build::is_bare_metal_target;
+use crate::utils::build::{is_bare_metal_target, is_compile_only, is_flat_bin};
 use std::fs;
 use std::path::{Path, PathBuf};
 use std::process::Command;
@@ -30,6 +30,9 @@ pub fn build(ctx: &BuildContext) -> Result<f64, String> {
     } else {
         ctx.compiler
     };
+    if is_flat_bin(ctx.kind) && ctx.qt {
+        return Err("flat-bin is not supported with build.qt = true".to_string());
+    }
     let start_time = Instant::now();
     let obj_dir = match ctx.target_dir {
         Some(dir) => Path::new(dir).join("obj"),
@@ -55,7 +58,7 @@ pub fn build(ctx: &BuildContext) -> Result<f64, String> {
     )?;
     let objects = build_objects(compiler, &sources, &obj_dir, ctx, "o", qt_include_path)?;
 
-    if ctx.kind == "none" || ctx.kind == "custom" {
+    if is_compile_only(ctx.kind) && !is_flat_bin(ctx.kind) {
         return Ok(common::elapsed_secs(start_time));
     }
 
@@ -142,7 +145,7 @@ fn build_object(
         cmd.arg("-fPIC");
     }
 
-    if (ctx.freestanding || is_bare_metal_target(ctx.target))
+    if (ctx.freestanding || is_bare_metal_target(ctx.target) || is_flat_bin(ctx.kind))
         && ctx.language.to_lowercase() != "asm"
     {
         cmd.arg("-ffreestanding");
@@ -178,8 +181,8 @@ fn build_object(
         }
     }
 
-    let use_dcr_defaults =
-        ctx.cflags.is_empty() && !(ctx.freestanding || is_bare_metal_target(ctx.target));
+    let use_dcr_defaults = ctx.cflags.is_empty()
+        && !(ctx.freestanding || is_bare_metal_target(ctx.target) || is_flat_bin(ctx.kind));
     if use_dcr_defaults {
         for flag in default_flags(ctx.profile) {
             cmd.arg(flag);

src/core/build/builder/msvc/mod.rs

@@ -16,8 +16,10 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 use crate::core::build::builder::BuildContext;
+use crate::core::build::builder::artifact;
 use crate::core::build::common;
 use crate::platform;
+use crate::utils::build::{is_compile_only, is_flat_bin};
 use std::fs;
 use std::path::Path;
 use std::process::Command;
@@ -33,6 +35,9 @@ pub fn build(ctx: &BuildContext) -> Result<f64, String> {
     if lang.contains("asm") {
         return Err("MSVC backend does not support build.language with asm".to_string());
     }
+    if is_flat_bin(ctx.kind) && ctx.qt {
+        return Err("flat-bin is not supported with build.qt = true".to_string());
+    }
     let start_time = Instant::now();
     let sources = collect_sources(ctx)?;
     let obj_dir = match ctx.target_dir {
@@ -41,10 +46,14 @@ pub fn build(ctx: &BuildContext) -> Result<f64, String> {
     };
     let objects = build_objects(compiler, &sources, &obj_dir, ctx, "obj")?;
 
-    if ctx.kind == "none" || ctx.kind == "custom" {
+    if is_compile_only(ctx.kind) && !is_flat_bin(ctx.kind) {
         return Ok(common::elapsed_secs(start_time));
     }
 
+    if is_flat_bin(ctx.kind) {
+        return link_flat_msvc(ctx, compiler, &objects, &obj_dir, start_time);
+    }
+
     if ctx.kind == "staticlib" {
         let lib_path = platform::lib_path(ctx.profile, ctx.project_name, ctx.target_dir);
         if !common::needs_link(&objects, &lib_path) {
@@ -145,6 +154,61 @@ pub fn build(ctx: &BuildContext) -> Result<f64, String> {
     }
 }
 
+fn link_flat_msvc(
+    ctx: &BuildContext,
+    compiler: &str,
+    objects: &[String],
+    obj_dir: &Path,
+    start_time: Instant,
+) -> Result<f64, String> {
+    let out_path = artifact::flat_output_path(ctx);
+    if !common::needs_link(objects, &out_path) {
+        return Ok(common::elapsed_secs(start_time));
+    }
+    fs::create_dir_all(obj_dir).map_err(|e| format!("obj dir error: {e}"))?;
+    let intermediate = obj_dir
+        .join(format!("{}.flat.exe", ctx.project_name))
+        .to_string_lossy()
+        .to_string();
+
+    let mut cmd = Command::new(compiler);
+    cmd.arg("/nologo");
+    for obj in objects {
+        cmd.arg(obj);
+    }
+    for flag in ctx.cflags {
+        cmd.arg(flag);
+    }
+    for dir in ctx.lib_dirs {
+        cmd.arg(format!("/LIBPATH:{dir}"));
+    }
+    for lib in ctx.libs {
+        if lib.to_lowercase().ends_with(".lib") {
+            cmd.arg(lib);
+        } else {
+            cmd.arg(format!("{lib}.lib"));
+        }
+    }
+    cmd.arg(format!("/Fe:{intermediate}"));
+    if !ctx.ldflags.is_empty() {
+        cmd.arg("/link");
+        for flag in ctx.ldflags {
+            cmd.arg(flag);
+        }
+    }
+    if ctx.verbose || std::env::var("DCR_DEBUG").is_ok() {
+        eprintln!("[dcr] {:?}", cmd);
+    }
+    let status = cmd
+        .status()
+        .map_err(|e| format!("flat-bin link failed: {e}"))?;
+    if !status.success() {
+        return Err("flat-bin link failed".to_string());
+    }
+    artifact::objcopy_binary(ctx, &intermediate, &out_path)?;
+    Ok(common::elapsed_secs(start_time))
+}
+
 pub(crate) fn collect_sources(ctx: &BuildContext) -> Result<Vec<String>, String> {
     let extensions = source_extensions(ctx.language);
     common::collect_sources(

src/core/build/cache.rs

@@ -107,6 +107,10 @@ fn build_cache_path(profile: &str, target_dir: Option<&str>) -> PathBuf {
 }
 
 fn build_output_path(ctx: &BuildContext) -> String {
+    if crate::utils::build::is_flat_bin(ctx.kind) {
+        return crate::core::build::builder::artifact::flat_output_path(ctx);
+    }
+
     let name = ctx.output_filename.unwrap_or(ctx.project_name);
     let ext = ctx.output_extension.unwrap_or("");
 
@@ -159,7 +163,13 @@ pub(crate) fn collect_header_files(
         if !root.exists() {
             continue;
         }
-        collect_header_files_rec(&root, &mut out, ctx.exclude_dirs, ctx.include_paths)?;
+        if root.is_file() {
+            if is_header_file(&root) {
+                out.push(root);
+            }
+        } else {
+            collect_header_files_rec(&root, &mut out, ctx.exclude_dirs, ctx.include_paths)?;
+        }
     }
     out.sort();
     out.dedup();

src/core/build/common.rs

@@ -35,7 +35,15 @@ pub fn collect_sources(
 ) -> Result<Vec<String>, String> {
     let mut sources = Vec::new();
     for root in roots {
-        collect_sources_rec(root, extensions, &mut sources, exclude_dirs, include_paths)?;
+        if root.is_file() {
+            if let Some(ext) = root.extension().and_then(|e| e.to_str())
+                && extensions.contains(&ext.to_lowercase().as_str())
+            {
+                sources.push(root.to_string_lossy().to_string());
+            }
+        } else {
+            collect_sources_rec(root, extensions, &mut sources, exclude_dirs, include_paths)?;
+        }
     }
     sources.sort();
     Ok(sources)

src/core/build/engine.rs

@@ -165,6 +165,9 @@ fn build_all(
                 &mut *rep,
             )?;
         }
+        if let Some(archive) = &config.typed().archive {
+            super::archive::pack_archive(root, archive, profile)?;
+        }
         return Ok(0.0);
     }
 
@@ -843,7 +846,10 @@ fn build_project_at(
         version_suffix: &version_info.suffix,
         version_suffix_dash: &version_info.suffix_dash,
     };
-    let steps_dirty = build_steps_need_run(&build_steps, &step_vars)?;
+    let mut steps_dirty = build_steps_need_run(&build_steps, &step_vars)?;
+    if force {
+        steps_dirty = true;
+    }
     if steps_dirty {
         clean_generated_files(&build_generated)?;
         run_build_steps(
@@ -884,7 +890,10 @@ fn build_project_at(
     if ctx.package_type == Some("lib") || ctx.kind == "staticlib" || ctx.kind == "sharedlib" {
         package_library(&ctx, &headers, project_root)?;
     }
-    let post_steps_dirty = build_steps_need_run(&build_post_steps, &step_vars)?;
+    let mut post_steps_dirty = build_steps_need_run(&build_post_steps, &step_vars)?;
+    if force {
+        post_steps_dirty = true;
+    }
     if post_steps_dirty {
         run_build_steps(
             &build_post_steps,
@@ -896,6 +905,9 @@ fn build_project_at(
         )?;
     }
     verify_expectations(&build_expects, &step_vars)?;
+    if let Some(archive) = &config.typed().archive {
+        super::archive::pack_archive(project_root, archive, profile)?;
+    }
     Ok(())
 }
 fn find_target_root(dir: &str, fallback: &Path) -> PathBuf {

src/core/build/language/asm/common.rs

@@ -1,6 +1,7 @@
 use crate::core::build::builder::BuildContext;
 use crate::core::build::builder::artifact;
 use crate::core::build::common;
+use crate::utils::build::{is_compile_only, is_flat_bin};
 use std::path::Path;
 use std::time::Instant;
 
@@ -22,13 +23,63 @@ pub fn build_assembly<F>(
     extensions: &[&str],
     build_object: F,
 ) -> Result<f64, String>
+where
+    F: Fn(&str, &str, &str, &BuildContext) -> Result<(), String> + Sync,
+{
+    build_assembly_with_mode(
+        ctx,
+        backend_name,
+        default_assembler,
+        extensions,
+        FlatEmit::Direct,
+        build_object,
+    )
+}
+
+pub fn build_assembly_via_objcopy<F>(
+    ctx: &BuildContext,
+    backend_name: &str,
+    default_assembler: &str,
+    extensions: &[&str],
+    build_object: F,
+) -> Result<f64, String>
+where
+    F: Fn(&str, &str, &str, &BuildContext) -> Result<(), String> + Sync,
+{
+    build_assembly_with_mode(
+        ctx,
+        backend_name,
+        default_assembler,
+        extensions,
+        FlatEmit::ViaObjcopy,
+        build_object,
+    )
+}
+
+#[derive(Clone, Copy)]
+enum FlatEmit {
+    Direct,
+    ViaObjcopy,
+}
+
+fn build_assembly_with_mode<F>(
+    ctx: &BuildContext,
+    backend_name: &str,
+    default_assembler: &str,
+    extensions: &[&str],
+    flat_mode: FlatEmit,
+    build_object: F,
+) -> Result<f64, String>
 where
     F: Fn(&str, &str, &str, &BuildContext) -> Result<(), String> + Sync,
 {
     let lang = ctx.language.to_lowercase();
-    if lang.split(',').any(|p| p.trim() != "asm") {
+    if lang.split(',').any(|p| {
+        let t = p.trim();
+        t != "asm" && t != "llvm_ir" && t != "llvm-ir" && t != "ll"
+    }) {
         return Err(format!(
-            "{backend_name} backend requires build.language = \"asm\""
+            "{backend_name} backend requires build.language = \"asm\" (or llvm_ir for LLC)"
         ));
     }
 
@@ -45,13 +96,48 @@ where
         ctx.exclude_dirs,
         ctx.include_paths,
     )?;
+
+    let flat = is_flat_bin(ctx.kind);
     let obj_dir = match ctx.target_dir {
         Some(dir) => Path::new(dir).join("obj"),
         None => Path::new("./target").join(ctx.profile).join("obj"),
     };
-    let objects = build_objects_common(assembler, &sources, &obj_dir, ctx, &build_object)?;
 
-    if ctx.kind == "none" || ctx.kind == "custom" {
+    let objects = match (flat, flat_mode) {
+        (true, FlatEmit::Direct) => {
+            let outs: Vec<String> = sources
+                .iter()
+                .map(|s| artifact::flat_source_output_path(ctx, s))
+                .collect();
+            common::parallel_build(
+                sources.len(),
+                |i| build_object(assembler, &sources[i], &outs[i], ctx),
+                ctx.codegen_units,
+            )?;
+            outs
+        }
+        (true, FlatEmit::ViaObjcopy) => {
+            let intermediates: Vec<String> = sources
+                .iter()
+                .map(|s| common::object_path(&obj_dir, s, "o"))
+                .collect();
+            common::parallel_build(
+                sources.len(),
+                |i| build_object(assembler, &sources[i], &intermediates[i], ctx),
+                ctx.codegen_units,
+            )?;
+            let mut outs = Vec::with_capacity(sources.len());
+            for (i, src) in sources.iter().enumerate() {
+                let out = artifact::flat_source_output_path(ctx, src);
+                artifact::objcopy_binary(ctx, &intermediates[i], &out)?;
+                outs.push(out);
+            }
+            outs
+        }
+        (false, _) => build_objects_common(assembler, &sources, &obj_dir, ctx, &build_object)?,
+    };
+
+    if is_compile_only(ctx.kind) {
         return Ok(common::elapsed_secs(start_time));
     }
 

src/core/build/language/asm/gas/mod.rs

@@ -32,7 +32,7 @@ pub fn build(ctx: &BuildContext) -> Result<f64, String> {
         .map(|s| s.trim().to_string())
         .filter(|s| !s.is_empty())
         .unwrap_or_else(|| "as".to_string());
-    asm::build_assembly(ctx, "GAS", &as_path, &["s"], build_object)
+    asm::build_assembly_via_objcopy(ctx, "GAS", &as_path, &["s"], build_object)
 }
 
 pub(crate) fn collect_sources(ctx: &BuildContext) -> Result<Vec<String>, String> {

src/core/build/language/asm/masm/mod.rs

@@ -6,7 +6,7 @@ use std::path::Path;
 use std::process::Command;
 
 pub fn build(ctx: &BuildContext) -> Result<f64, String> {
-    asm::build_assembly(ctx, "MASM", "ml", &["asm"], build_object)
+    asm::build_assembly_via_objcopy(ctx, "MASM", "ml", &["asm"], build_object)
 }
 
 pub(crate) fn collect_sources(ctx: &BuildContext) -> Result<Vec<String>, String> {

src/core/build/language/asm/nasm/mod.rs

@@ -50,7 +50,11 @@ fn build_object(
         return Ok(());
     }
 
-    let format = nasm_format(ctx.platform);
+    let format = if crate::utils::build::is_flat_bin(ctx.kind) {
+        "bin"
+    } else {
+        nasm_format(ctx.platform)
+    };
 
     let mut cmd = Command::new(assembler);
     cmd.arg("-f")

src/core/build/language/llvm_ir/mod.rs

@@ -21,7 +21,7 @@ impl Language for LlvmIr {
 }
 
 pub fn build(ctx: &BuildContext) -> Result<f64, String> {
-    asm::build_assembly(ctx, "LLVM-IR", "llc", &["ll"], build_object)
+    asm::build_assembly_via_objcopy(ctx, "LLVM-IR", "llc", &["ll"], build_object)
 }
 
 pub(crate) fn collect_sources(ctx: &BuildContext) -> Result<Vec<String>, String> {

src/core/build/mod.rs

@@ -15,6 +15,7 @@
 // You should have received a copy of the GNU General Public License
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
+pub mod archive;
 pub mod builder;
 pub mod cache;
 pub mod common;

src/core/build_config.rs

@@ -36,6 +36,7 @@ const VALID_KINDS: &[&str] = &[
     "elf",
     "none",
     "custom",
+    "flat-bin",
 ];
 
 #[derive(Debug)]
@@ -102,6 +103,27 @@ pub struct DcrConfig {
     pub toolchain: Option<ToolchainConfig>,
     #[serde(default)]
     pub workspace: BTreeMap<String, WorkspaceMemberConfig>,
+    #[serde(default)]
+    pub archive: Option<ArchiveConfig>,
+}
+
+#[allow(dead_code)]
+#[derive(Debug, Clone, Deserialize)]
+pub struct ArchiveConfig {
+    pub output: String,
+    pub format: String,
+    pub size: Option<String>,
+    pub offset: Option<String>,
+    pub label: Option<String>,
+    pub bootsector: Option<String>,
+    #[serde(default)]
+    pub layout: Vec<ArchiveLayout>,
+}
+
+#[derive(Debug, Clone, Deserialize)]
+pub struct ArchiveLayout {
+    pub from: String,
+    pub to: String,
 }
 
 #[derive(Debug, Clone, Deserialize)]