Solana BPF Programs with Zig + sbpf-linker

A minimal template for building Solana BPF programs using standard Zig compiler and sbpf-linker.

Features

• ✅ Uses standard Zig BPF target (no custom forks)
• ✅ Zero external dependencies (no SDK needed)
• ✅ LLVM bitcode generation via -femit-llvm-bc
• ✅ Direct syscall invocation via function pointers
• ✅ Automated build pipeline with zig build
• ✅ Jest-based integration tests with solana-test-validator

Prerequisites

# Install sbpf-linker (must be in ../sbpf-linker)
git clone https://github.com/blueshift-gg/sbpf-linker.git ../sbpf-linker
cd ../sbpf-linker && cargo build

# Install Zig 0.15.2 or later
# Install Node.js for testing

Building

zig build

This generates:

1. entrypoint.bc - LLVM bitcode from Zig source
2. zig-out/lib/program_name.so - Final Solana program

Testing

npm install
npm test

Tests will:

• Build the program
• Start solana-test-validator
• Deploy the program
• Execute and verify "Hello world!" log output

How It Works

1. Direct Syscalls via Function Pointers

Instead of using extern declarations (which get optimized away), we call Solana syscalls directly:

const sol_log_ = @as(*align(1) const fn ([*]const u8, u64) void, @ptrFromInt(0x207559bd));
sol_log_(message.ptr, message.len);

The magic constant 0x207559bd is the syscall hash that Solana VM resolves at runtime.

2. Inline String Data

To prevent sbpf-linker from stripping .rodata, we inline string data:

const message = [_]u8{'H','e','l','l','o',' ','w','o','r','l','d','!'};

3. LLVM Bitcode Pipeline

sbpf-linker is an LTO compiler, not a traditional linker. It needs LLVM IR:

zig build-lib -target bpfel-freestanding -femit-llvm-bc=entrypoint.bc
sbpf-linker --cpu v3 --export entrypoint -o program.so entrypoint.bc

Project Structure

.
├── build.zig           # Automated build pipeline
├── build.zig.zon       # Zero dependencies
├── src/
│   └── entrypoint.zig  # Program entrypoint with inline syscalls
└── test/
    └── program.test.ts # Integration tests

License

MIT