Callosum tech stack
Callosum builds mostly with Python, C++, Erlang, Rust. Its stack also includes Cerebras, CUDA Toolkit, CUDA, PyTorch. Cerebras is named in 16 of the 16 job postings Callosum published in the last 12 months (100%). Counted by Alion from the job postings of Callosum, updated Sep 28, 2026.
What programming languages does Callosum use?
Python is named in 25% of job postings at Callosum, followed by C++ (13%), Erlang (6%), Rust (6%).
What frameworks and libraries does Callosum use?
CUDA is named in 13% of job postings at Callosum, followed by PyTorch (13%), SGLang (13%), JAX (6%).
PyTorch
2 13%
SGLang
2 13%
JAX
1 6%
OpenTelemetry
1 6%
PyTorch C++
1 6%
Show all (11)
What cloud and platforms does Callosum use?
Cerebras is named in 100% of job postings at Callosum, followed by CUDA Toolkit (13%), vLLM (13%), Apache Kafka (6%).
Cerebras 
What developer tools does Callosum use?
Prometheus is named in 6% of job postings at Callosum, followed by Triton Inference Server (6%).
Prometheus
1 6%
What AI and ML technologies does Callosum use?
LLM is named in 19% of job postings at Callosum.
LLM
3 19%
Which engineering practices does Callosum ask for?
AI Agents is named in 44% of job postings at Callosum, followed by Machine Learning (25%), Function Calling (19%), LLM Evaluation (19%).
AI Agents
7 44%
Function Calling
3 19%
CI/CD
1 6%
Show all (12)
What does each Callosum team work with?
The technologies each team's postings require most often, with the number of postings that require them.
AI/ML
15 postingsHow does your stack fit Callosum?
How is the Callosum stack changing?
Read from the dates of the postings themselves: a technology is new when the first posting that names it appeared in the last six months, rising or falling when its share of postings moved between the last two quarters.
How modern is the Callosum stack?
Callosum scores 73 out of 100 (Modern). The score averages how current each technology in the stack is and adds weight for AI adoption. AI technologies in the stack: 1; legacy ones: 0.
Companies with a stack like Callosum
Questions about the Callosum tech stack
What programming languages does Callosum use?
The languages named in Callosum job postings are Python (25%), C++ (13%), Erlang (6%), Rust (6%), as a share of the 16 postings of the last 12 months.
Does Callosum use CUDA?
Yes. CUDA is named in 2 of 16 job postings (13%) and required in 2 of them.
What cloud and platforms does Callosum use?
The cloud and platforms named in Callosum job postings are Cerebras (16), CUDA Toolkit (2), vLLM (2) (postings in brackets).
What skills do you need for a AI/ML job at Callosum?
AI/ML postings at Callosum most often require Cerebras (15), Python (4), LLM (3), C++ (2), out of 15 postings in the last 12 months.
Is the Callosum tech stack changing?
Yes. PyTorch, Machine Learning, Function Calling, Tool Use first appeared in Callosum job postings in the last six months.
How modern is the Callosum tech stack?
Callosum scores 73 out of 100 (Modern). The score averages how current each technology in the stack is and adds weight for AI adoption. AI technologies in the stack: 1; legacy ones: 0.
How does Alion know the Callosum tech stack?
Alion reads every job posting Callosum publishes and tags the technologies each one names. The figures on this page count the 16 postings of the last 12 months and were updated on Sep 28, 2026.
Method and citation
Alion reads every job posting the company publishes and tags the technologies each one names. Shares count the postings of the last 12 months, open and closed; the company's own products are counted apart. How we count
Alion, "Callosum tech stack: 36 technologies from 16 job postings", as of Sep 28, 2026. https://alion.io/company/callosum/technologies