Some developers write code. Others understand the symbols behind it.

λ + ∇ + Σ

Abstraction. Optimization. Aggregation.

• λ (Lambda) — the foundation of functional programming and anonymous functions. The symbol behind composability, higher-order logic, and modern language design.
• ∇ (Nabla) — the gradient operator. Core to optimization, machine learning, physics engines, and numerical systems.
• Σ (Sigma) — summation. The basis of iteration, accumulation, and algorithms that build results step by step.

Together, they represent the underlying language of systems, mathematics, and software engineering.

A minimal design that speaks to engineers who understand what happens beneath the surface.

Foundational. Mathematical. Intentional.

Recognizable only to those who know.

λ + ∇ + Σ

Product details

100% organic ring-spun cotton
5.3 oz./yd² (180 g/m²)
Single jersey construction
Medium fit
Set-in sleeves
1 × 1 ribbed collar
Double-needle stitching (sleeves & hem)
Self-fabric neck tape

Certified under GOTS, OCS, OEKO-TEX Standard 100, and PETA-Approved Vegan.

Blank product sourced from Bangladesh.

Note: Sizes correspond to a smaller fit in the US market. US customers may prefer ordering one size up.

Made on demand

This product is made especially for you after purchase, reducing overproduction.

Compliance

• Traceability:
- Weaving—Bangladesh
- Dyeing—Bangladesh
- Manufacturing—Bangladesh
• Contains 0% recycled polyester
• Contains 0% dangerous substances

Age restrictions: For adults
EU Warranty: 2 years
Meets EU REACH requirements

In compliance with the General Product Safety Regulation (GPSR), Developers Threads and SINDEN VENTURES LIMITED ensure product safety and EU standards.
Contact: gpsr@sindenventures.com
Address: Markou Evgenikou 11, Limassol, Cyprus

Size guide