Steel Bank Common Lisp

What Steel Bank Common Lisp does

Steel Bank Common Lisp (SBCL) is a volunteer-maintained open source project that provides a high-performance ANSI Common Lisp compiler and runtime system. Descended from CMU Common Lisp (which itself traces back to Spice Lisp at Carnegie Mellon in the 1980s), SBCL implements a compiler-only approach in which eval compiles code on the fly, and is written primarily in Lisp with a C runtime. The system runs on Linux, various BSDs, macOS, Solaris, and Windows, and supports x86, x86-64, ARM, SPARC, Alpha, MIPS, and PowerPC CPU architectures. SBCL is used by professional software developers, academic researchers, and hobbyists who require a standards-compliant, high-performance Common Lisp implementation.

The core product includes the compiler, runtime, interactive debugger, statistical profiler (sb-sprof), and code coverage tool (sb-cover), along with an extensive ecosystem of contributed modules: sb-simd for SIMD operations, sb-concurrency for threading primitives including lock-free mailboxes and queues, sb-alien for foreign function interfacing to C, sb-bsd-sockets for TCP/UDP networking, sb-introspect for introspection, sb-posix for POSIX facilities, sb-grovel for automating FFI generation, and sb-md5 for cryptographic primitives. SBCL is tightly integrated with the SLIME development environment for Emacs, and delivers standalone executables via save-lisp-and-die.

SBCL is distributed as free software under a permissive license with no pricing, subscriptions, or commercial tiers. The project has no formal corporate structure, parent company, or institutional ownership; development is community-driven through volunteer maintainers who accept patches and manage releases. Distribution occurs via SourceForge downloads, the official sbcl.org website, and source tarballs, with community support provided through the sbcl-help and sbcl-devel mailing lists and the Launchpad bug database. There is no commercial go-to-market, no sales motion, and no revenue generation from the software itself.

Name

Steel Bank Common Lisp

Legal name

Steel Bank Common Lisp

Website

https://www.sbcl.org

Company type

Private

Operating status

Operating

Headcount range

101–250 employees

Short description

Steel Bank Common Lisp (SBCL) is a volunteer-maintained, open source high-performance ANSI Common Lisp compiler and runtime system serving professional developers, academic researchers, and hobbyists across multiple operating systems and CPU architectures.

Ownership category

akta.pro rank

Product category

Programming Language Implementation

NAICS

Software Publishers (51321)

SIC

Services-Prepackaged Software (7372), Services-Computer Programming, Data Processing, Etc. (7370)

akta.pro primary industry

Release Engineering & Environment Management (BPAEAKAH)

Keywords

• Common Lisp compiler
• Lisp runtime system
• Open source compiler
• Developer tools
• Programming language implementation

Headquarters

HQ city

Wilmington

HQ country

United States

HQ region

North America

Markets served

GTM type

B2B

Offering type

Software

Cost components

Personnel, Technology or R&D, Infrastructure, Operations

Revenue model

1. Open Source Distribution: SBCL is distributed as free open source software under a permissive license. No revenue is generated from the software itself. The project is maintained by volunteers with no commercial entity backing it.

Pricing tiers

Go-to-market motion1 record

Distribution channels3 records

Marketing channels5 records

Core offering

Steel Bank Common Lisp (SBCL) is an open-source, high-performance ANSI Common Lisp compiler and runtime system distributed free of charge under a permissive license. Beyond the compiler and runtime, it ships an interactive development environment including a debugger, statistical profiler, and code coverage tool, and is extended through loadable contributed modules such as sb-simd, sb-concurrency, sb-bsd-sockets, sb-introspect, sb-posix, sb-grovel, sb-md5, sb-cover, sb-aclrepl, sb-queue, sb-rotate-byte, sb-alien (FFI), and sb-mop. SBCL runs on Linux, BSDs, macOS, Solaris, and Windows across multiple CPU architectures and produces standalone executables for production deployment.

Product overview

Steel Bank Common Lisp (SBCL) is a single, unified high-performance ANSI Common Lisp compiler and runtime system. It is open source/free software with a permissive license. The core product includes the compiler, runtime system, interactive debugger, statistical profiler, and code coverage tool. SBCL is extended through numerous loadable contributed modules including sb-simd (SIMD operations), sb-concurrency (threading primitives), sb-bsd-sockets (networking), sb-introspect (introspection), sb-posix (POSIX interface), sb-grovel (FFI automation), sb-md5 (cryptography), sb-cover (testing), sb-aclrepl (REPL alternative), sb-queue, sb-rotate-byte, and sb-alien (foreign function interface). Documentation is provided as a comprehensive user manual in HTML and PDF formats.

Differentiator

Problem solved

Functional benefit

Products and services

• SBCL (Steel Bank Common Lisp) Compiler and Runtime High-performance ANSI Common Lisp compiler and runtime system. Includes an interactive environment with debugger, statistical profiler, and code coverage tool. Distributed for Linux, BSDs, macOS, Solaris, and Windows across multiple CPU architectures.
• SBCL User Manual Comprehensive documentation for SBCL available in HTML and PDF formats, covering the compiler, debugger, threading, networking, and extensions. The manual is largely derived from the CMUCL manual and is in the public domain.

Quantifiable outcome

• High-performance compilation comparable to or exceeding commercial Lisp implementations
• +2 more outcomes

Segments2 records

Ideal customer profiles2 records

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Integration1 record

Feature12 records

Scale indicators3 records

Recent moves3 records

Expansion highlights3 records

Direct peers

• GNU CLISP: Another free, open-source ANSI Common Lisp implementation with broad platform support. Closely comparable as a direct alternative SBCL user can choose when selecting a free Lisp compiler.
• Clozure CL: Open-source Common Lisp implementation focused on macOS and Linux with native threading. Directly competes with SBCL as a free, high-performance Lisp compiler/runtime choice.
• Embeddable Common Lisp (ECL): Open-source Common Lisp implementation designed for embedding in C applications and compilation to standalone executables. Comparable to SBCL on cross-platform deployment and C interop use cases.
• Armed Bear Common Lisp (ABCL): Common Lisp implementation running on the JVM, distributed as open-source software. A direct peer offering an alternative free Lisp runtime with a different delivery model than SBCL.
• CMUCL: The Carnegie Mellon University Common Lisp implementation from which SBCL was forked in 2000. A direct ancestor peer sharing lineage, compiler architecture heritage, and ANSI Common Lisp compliance focus.
• GNU Common Lisp (GCL): GNU Project's open-source Common Lisp implementation with strong integration into the GNU toolchain. Comparable to SBCL as a free Lisp implementation, particularly for systems-integrated deployments.

Broad incumbents

• Franz Allegro CL: Commercial Common Lisp development environment from Franz Inc., historically dominant in commercial Lisp. Comparable to SBCL as an ANSI Common Lisp implementation but sold as a commercial product with support and IDE tooling.
• LispWorks: Commercial Common Lisp development environment with IDE and deployment tools. Comparable to SBCL for production Common Lisp users but positioned as a paid commercial alternative.

Emerging players

• ManKai Common Lisp (MKCL): Open-source fork of ECL maintained by Jean-Claude Beaudoin, emphasizing portability and embedding. Comparable to SBCL/EGL as a free, embeddable Common Lisp runtime with active development.

Others

• SLIME (Superior Lisp Interaction Mode for Emacs): The recommended Emacs-based development environment for SBCL, providing debugger, REPL, and documentation integration. Adjacent rather than competitive, but materially coupled to SBCL's developer experience.

Market position

Strengths4 records

Weaknesses4 records

Competitive moat4 records

Key risks5 records

Key highlights6 records

Customer concentration

• LinkedInlinkedin.com/company/sbcl-inc

Revenue estimate

Valuation estimate

Number of profiles

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Steel Bank Common Lisp