# Upgrade Boost > Build Boost for hMailServer and/or bump the pinned Boost version, for 1.x (e.g. rebuild 1.90.0, or upgrade 1.89.0 -> 1.90.0). Builds the static x64 Boost libraries hMailServer links against into %hMailServerLibs% via libraries\build-boost.ps1, rewrites every pinned Boost version reference in the repo, keeps the README build instructions current, and verifies hMailServer still compiles and links. Use when asked to build, rebuild, bump, update, or upgrade Boost for hMailServer. Supports Boost 1.x only. - Skill: `hmailserver/upgrade-boost` (Agent Skill) - Install (CLI): `npx skillmds@latest add hmailserver/upgrade-boost` - Raw SKILL.md: https://api.skillmd.com/api/skills/hmailserver/upgrade-boost/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Coding & Dev Tools - Author: hmailserver (https://skillmd.com/u/hmailserver) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/hmailserver/upgrade-boost --- # Build / upgrade Boost (1.x) for hMailServer hMailServer links against a handful of compiled Boost libraries (thread, filesystem, regex, chrono, system, atomic) plus many header-only ones. Boost is not vendored in the repo; it is built locally into `%hMailServerLibs%\boost_` (e.g. `boost_1_90_0`), and its concrete version is pinned in the project files and README. This skill builds Boost, rewrites those references when the version changes, and verifies the build. There are two reasons to run it: - **Rebuild Boost** at the *current* pinned version — e.g. after switching VS toolset or a clean checkout of the libs folder. No version rewrites needed. - **Bump the Boost version** (e.g. `1.89.0 -> 1.90.0`) — build the new version *and* rewrite the pinned references. ## Scope - **Boost 1.x only** (built with the `bootstrap` + `b2` build system). Reject anything not matching `^1\.\d+\.\d+$`. - Boost is linked **statically** (`link=static`), so the `.lib` files are pulled in at link time and there is **no Boost DLL** to copy in `post-build.bat` or ship in the installer — that is why Boost, unlike OpenSSL/libpq, has no touch points in `post-build.bat`, `section_files_64.iss`, or `hMailServer64.iss`. - The compiled libs are built with the **msvc-14.2** toolset (v142 - VS2019, or VS2022 with the "MSVC v142 build tools" component), matching the rest of hMailServer. Updating any CI/CD-built copy of Boost is out of scope, but the README build instructions must stay accurate. ## Steps ### 1. Determine current and target version - Read the current Boost version by searching `hmailserver/source/Server/hMailServer/hMailServer.vcxproj` for `boost_(\d+_\d+_\d+)` (e.g. `boost_1_90_0` -> `1.90.0`). - Take the target version from the user (e.g. `1.90.0`). For a pure rebuild, the target equals the current version. - **Validate the target matches `^1\.\d+\.\d+$`.** Abort with the out-of-scope message above if it does not. - If current == target and this is not an explicit rebuild request, there is nothing to do — say so and stop. ### 2. Build Boost Invoke the build script (prerequisites — `%hMailServerLibs%`, VS2019/VS2022 x64 tools — are validated inside it; surface its error message if it fails): ``` powershell.exe -NoProfile -ExecutionPolicy Bypass -File libraries\build-boost.ps1 -Version ``` Pass `-Toolset ` to override the default `msvc-14.2`, or `-Jobs ` to change the parallelism (defaults to the number of logical processors). **Run this through the native PowerShell tool, NOT the Bash tool.** The Bash tool prepends MSYS/Git (`/usr/bin`) to `PATH`, which puts a GNU `tar` ahead of the Windows `bsdtar` (GNU tar misreads the `C:` in `C:\...` as a remote rmt host — "Cannot connect to C: resolve failed"). The native PowerShell tool has a clean Windows `PATH`. The script also pins tar to `%SystemRoot%\System32\tar.exe` defensively. The build takes several minutes and the PowerShell tool only returns its captured output once it finishes, so the console can look stalled. The script mirrors every step to `libraries\build-boost.log` (git-ignored via `*.log`) as it runs. Tell the user they can watch progress live from another shell with `Get-Content libraries\build-boost.log -Wait`, and if the script fails, read that log for the full transcript rather than relying on the (often truncated) captured console output. On success it produces `%hMailServerLibs%\boost_` with the Boost headers under `boost\` and the staged static libs under `stage\lib` (e.g. `libboost_thread-vc142-mt-x64-1_90.lib`). Only proceed if the script exits 0. ### 3. Rewrite the pinned version references **Skip this step for a pure rebuild** (target == current). Otherwise replace the old underscored version with the new one (`boost_` -> `boost_`, e.g. `boost_1_89_0` -> `boost_1_90_0`) in these files: | File | Occurrences | |------|-------------| | `hmailserver/source/Server/hMailServer/hMailServer.vcxproj` | 4 (include-dir + lib-dir, across Debug and Release) | | `hmailserver/source/Server/hMailServer.Minidump/hMailServer.Minidump.vcxproj` | 4 (include-dir + lib-dir, across Debug and Release) | | `README.md` | 2 (the dotted "Boost 1.90.0" version in the download step and the `boost_1_90_0` example folder name) | Then grep the whole repo for `boost_\d+_\d+_\d+` and the dotted `Boost \d+\.\d+\.\d+`, and confirm the only remaining matches are the intentional ones you just rewrote — there must be **zero** references to the old concrete version. **Do not** change the `` placeholder in the README (it is generic) or the `#include ` directives throughout the source (not version-bearing). ### 4. Keep build instructions current The `README.md` "Building Boost" section documents the manual `bootstrap` / `b2` recipe the script automates (step 3 already covers the version strings). Skim the new release's notes; only if Boost changed the build process (bootstrap/b2 flags, staged lib naming) update both `libraries\build-boost.ps1` and the README accordingly. State whether a change was needed. ### 5. Verify Build hMailServer to confirm it compiles and links against the new Boost: ``` powershell.exe -NoProfile -ExecutionPolicy Bypass -File build\build.ps1 ``` The compile step pulls the Boost headers from `boost_` and the link step pulls the static libs from `boost_\stage\lib`, so a successful build confirms the reference updates are consistent. Because Boost is linked statically there is no DLL to copy — no `post-build` or installer changes are involved. ## Reference: all Boost touch points - **Version-pinned (edited by step 3):** `hMailServer.vcxproj`, `hMailServer.Minidump.vcxproj`, `README.md`. - **Build recipe (edited only if the release changes it):** `libraries\build-boost.ps1`, `README.md`. - **Not version-bearing (leave alone):** the `#include ` directives across the source tree; the `$(BOOST_INCLUDE_PATH)` / `$(BOOST_LIBS_PATH)` MSBuild fallbacks in the project files; the `` placeholder in the README. ## Note The script's own end-to-end run needs the Boost source download and the VS2019/VS2022 x64 toolchain present; it validates those prerequisites and fails early with a clear message if any is missing.